Hepatitis C virus (HCV) infection is a worldwide public health problem. Chronic infection by HCV can lead to liver cirrhosis or cancer. Although some immune-competent individuals can clear the virus, others develop chronic HCV disease due to viral mutations or an impaired immune response. IFNs type I and III and the signal transduction induced by them are essential for a proper antiviral effect. Research on the viral cycle and immune escape mechanisms have generated the basis of therapeutic strategies to achieve a sustained virological response (SVR). The first therapies were based on IFN-, then IFN-α plus ribavirin (IFN-RBV); then, pegylated-IFN--RBV (PEGIFNα-RIV) to improve cytokine pharmacokinetics. However, the maximum SVR was 60%, and several significant side effects were observed, decreasing the patients' treatment adherence. The development of direct-acting antivirals (DAAs) significantly enhanced SVR (> 90%); the compounds were able to inhibit HCV replication without significant side effects, even in pediatric populations. The management of coinfected patients HBV-HCV and HCV-HIV has also improved based on DAA and PEG-IFNα-RBV (HBV-HCV). CD4 cells are crucial for an effective antiviral response. IFNλ3, IL28B, TNF-α, IL-10, TLR-3, and TLR-9 gene polymorphisms are involved in viral clearance, therapeutic responses, and hepatic pathologies. Future research focuses on searching for strategies to circumvent resistance-associated substitution (RAS) to DAAs, develop new therapeutic schemes for different medical conditions, including organ transplant, and develop vaccines for long-lasting cellular and humoral responses with cross-protection to different HCV genotypes. The goal is to minimise the probability of HCV infection, HCV chronicity and hepatic carcinoma.

Neuraminidase (NA)-based immunity could reduce the harmful impact of novel antigenic variants of influenza viruses. Detection of neuraminidase-inhibiting (NI) antibodies in parallel with anti-hemagglutinin (HA) antibodies may enhance research of immunogenicity and duration of antibody response to influenza vaccines. To assess anti-NA antibodies after vaccination with seasonal inactivated influenza vaccines, we used the enzyme-linked lectin assay, and anti-HA antibodies were detected in hemagglutination inhibition assay. The dynamics of anti-NA antibody response differed depending on the virus subtype: antibodies to A/H3N2 virus neuraminidase increased later than antibodies to A/H1N1pdm09 subtype neuraminidase, and persisted longer. In contrast to HA antibodies, the fold increase in antibody titers to NA after vaccination poorly depended on the preexisting level. At the same time, NA antibody level after vaccination directly correlated with titers before vaccination. Difference was found in response to NA antigen between split and subunit adjuvanted vaccines and in NA functional activity in the vaccine formulations.

Immune surveillance and adaptive immune responses, involving continuously circulating and tissue-resident T-lymphocytes, provide host defense against infectious agents and possible malignant transformation while avoiding autoimmune tissue damage. Activation, migration, and deployment of T-cells to affected tissue sites are crucial for mounting an adaptive immune response. An effective adaptive immune defense depends on the ability of T-cells to dynamically reprogram their metabolic requirements in response to environmental cues. Inability of the T-cells to adapt to specific metabolic demands may skew cells to become either hyporesponsive creating immunocompromised conditions or hyperactive causing autoimmune tissue destruction. Here, we review maladaptive T-cell metabolic fitness that can cause autoimmune diseases and discuss how T-cell metabolic programs can potentially be modulated to achieve therapeutic benefits.

Mycobacterium tuberculosis is the agent of tuberculosis, one of the most important infectious diseases in the world. This microorganism stands out from other bacteria, not only for its extremely high infection capacity, but also for its cellular characteristics that include an extremely resistant and hydrophobic cellular parade the passage of antibiotics. An incredible ability to adapt to adverse conditions inside the host as well as its vast arsenal of virulence factors that allow its survival within the inhospitable environment within the macrophage can be highlighted. This review aims to discuss several aspects of MTB microbiology, genetics, and physiology. We will address in this review details of the metabolism of MTB that allows it to replicate in the active phase and remain viable during latency, as well as the characteristics of its cell wall that contribute to the blockade of the immune response and its resistance to antibiotics.

Enterocins are bacteriocins synthesized by Enterococcus strains that show an interesting antimi-crobial effectiveness against foodborne pathogens such as Listeria monocytogenes. The objectives of this study were identify and analyze the expression of enterocin genes of Enterococcus isolated from breast-fed infants and evaluate the ability to inhibit three human isolates of virulent Lis-teria monocytogenes, as well as some probiotic bacteria. The susceptibility of the strains of L. mon-ocytogenes to fifteen antibiotics was tested, detecting resistance to cefoxitin (constitutive-ly resistant), oxacillin and clindamycin. Production of enterocins A, B and P were observed in Enterococcus faecium isolates, and enterocin AS-48 in an Enterococcus faecalis isolate. AS-48 showed antilisterial activity by itself, while the joint action of enterocins A and B, or B and P was neces-sary for inhibiting L. monocytogenes, demonstrating a synergistic effect of those combinations. The presence of multiple enterocin genes does not assured the inhibition of L. monocytogenes strains. However, the expression of multiple enterocin genes showed a good correlation with the inhibition capacity of these strains. Furthermore the potential beneficial strains of lactobacil-li and bifidobacteria examined were not inhibited by any of the enterocins produced individu-ally or in combination, with the exception of Bifidobacterium longum BB536, which was inhibited by enterocin AS-48 and the joint production of enterocins A and B or B and P. The enterocins studied here could be candidates for developing alternative treatments against antibi-otic-resistant bacterial infections. Moreover, these selected enterocin-producing E. faecium strains isolated from breast-fed infants could be used as probiotic strains due to their antilisterial effect as well as the absence of virulence factors.

The required processes and steps for making bread include technological and innovative concepts. The current trend is the use of less toxic compounds and green processes. Besides lactic acid bacteria and yeast, other microorganisms with special properties, such as enzymes, new aroma and flavor, exopolysaccharides, and vitamins, among other compounds with beneficial properties, could be added to bread manufacture, improving bread quality and health effects for the consumers. Freeze drying, new encapsulation methods, cryoprotectants, spray drying, fluidized bed drying, and vacuum drying are used for probiotics and microorganism cultures that will be used as starters or biological additives in the fermentation. The same development is observed in the preservation methods, and studies with plant extracts and essential oils have been proposed and introduced, replacing chemical agents, such as propionate, within the clean-label bread formulations concept. Baking science is a growing research line incorporating innovative methods and biological additives.

Interferons were the original prototype cytokine system discovered in 20th-century research. As the name implies, they were originally thought to be synthesised and secreted between cells. Thanks to technological advances, the processes involved in protein secretion can be explained comparatively more clearly at both the genetic and biochemical levels. The discovery of interferon (IFN) occurred when genetic research was still in its infancy. Franklin and Wilkins discovered the structure and function of deoxyribonucleic acid (DNA) at the same time as Crick and Watson; however, Isaacs and Lindemann, two scientists, described the first IFN in 1957. Mutations can be caused by inherent genetic protein synthesis and during infection as well as within IFN regulation pathways affecting cell proliferation. This remains central to host cell IFN synthesis and effects through IFN protein receptor subunits defined by 6 protein domains. Type II IFN is key to immune cell function secreted by a variety of immune cells, mainly natural killer (NK) as well as T cells. Single–stranded and/or double–stranded RNA/DNA viruses, as well as bacterial infections (e.g., Escherichia coli) and fungal infections (e.g., Aspergillus), also affect IFN regulation. Pathogenic proteins utilise intra/extracellular proteins that sense foreign antigens like Toll–like Receptors (TLRs), affected by mutations within the human cellular IFN transduction pathways. Since the discovery of the third IFN type in 2003, when immune cell phenotypes were further characterised, questions remain about the immunological mechanisms contributing to the regulation of the innate and adaptive host immune system. Alterations in the synthesis of type I/II/III host IFNs can differentially and beneficially alter homeostatic cellular pathways in pathological disease, with type I IFN being synthesised in cancer as well as by homeostatic cells. Therefore, considered here are the overall IFN molecular, cell regulatory mechanisms in the context of immune cell research developments.

Macrophages serve as vital defenders, protecting the body by exhibiting remarkable cellular adaptability in response to invading pathogens and various stimuli. These cells express nicotinic acetylcholine receptors, with the α7-nAChR being extensively studied due to its involvement in activating the cholinergic anti-inflammatory pathway. Activation of this pathway plays a crucial role in suppressing macrophages' production of proinflammatory cytokines, thus mitigating excessive inflammation and maintaining host homeostasis. Macrophage polarization, which occurs in response to specific pathogens or insults, is a process that has received limited attention concerning the activation of the cholinergic anti-inflammatory pathway and the contributions of the α7-nAChR in this context. This review aims to present evidence highlighting how the cholinergic machinery in macrophages, led by the α7-nAChR, facilitates the polarization of macrophages towards anti-inflammatory phenotypes. Additionally, we explore the influence of viral infections on macrophage inflammatory phenotypes, taking into account cholinergic mechanisms. We also review the current understanding of macrophage polarization in response to these infections. Finally, we provide insights into the relatively unexplored partial duplication of the α7-nAChR, known as dup α7, which is emerging as a significant factor in macrophage polarization and inflammation scenarios.

This study continued the analysis of immunization with the receptor binding domain (RBD) associated with the adjuvants Dimethyldioctadecylammonium bromide (DDA) and Saponin (Sap) (RBD+DDA/Sap) or Aluminum hydroxide (AH) and outer membrane vesicles (OMVs) of Neisseria meningitidis (RBD+AH/OMV); from adult to old age and assessed maternal-fetal transference of antibodies. Outbred Swiss mice were immunized with 2 intramuscular (IM) doses with the antigenic preparations RBD+DDA/Sap, RBD+AH/OMV or RBD alone. The humoral immune response was evaluated using ELISA, avidity-ELISA, Immunoblotting and a Omicron-surrogate-neutralization assay (BA.1), while the cellular immune response was analyzed by ELISpot. Our previous work studied the IgG response; here, we verified that IgM levels were higher right after the immunization doses, but, as IgG, it persisted until 368 days after the immunization. The avidity of IgM increased from low to intermediate-to-high after the booster dose. RBD+DDA/Sap presented neutralizing indexes against Omicron at days 47 and 176, while RBD+AH/OMV showed neutralization on days 21, 47 and 176. Cellular response, measured 465 days after immunization, revealed IFN-Y and IL-4 secretion. The offspring of RBD+DDA/Sap had detectable antibodies, which decreased around 45 days after birth, the last point we analyzed. The results suggested that DDA/Sap is a promising adjuvant mixture to enhance humoral and cellular immune response against SARS-CoV-2, improving maternal-fetal transference of antibodies; cross-reactivity with Omicron variant; and the maintenance of antibodies for a long period.

A biofilm is any syntrophic consortium of microorganisms in which cells adhere to one another and, in some cases, to a surface. These adherent cells become encased in a slimy extracellular matrix made up of extracellular polymeric substances (EPSs). Until now, the use of commercial disinfectants remains the main strategy to control biofilm-mediated problems. This mini review summarizes common antibiofilm mode of actions taken by disinfectants and how water channels in microbial biofilms contribute to disinfectant resistance.

Understanding the energy metabolism and its regulation is one of the clues to metabolic engineering of stress-resistant lignocellulose-converting microbial strains, including also the promising ethanologen Zymomonas mobilis. Z. mobilis is an obligately fermentative, facultatively anaerobic bacterium, carrying an active respiratory chain with a low energy-coupling efficiency. Its respiration does not supply energy to aerobically growing culture on sugary media, yet oxidative phosphorylation has been demonstrated in non-growing cells with ethanol. In the present work we show that in respiring, non-growing Z. mobilis cells, receiving regular small amounts of ethanol, oxidative phosphorylation significantly contributes to the maintenance of their viability. Accordingly, no improvement of viability is seen in the NADH dehydrogenase (ndh)-deficient respiratory mutant, unable to oxidize ethanol. The ethanol effect is hampered also by the protonophoric uncoupler CCCP, or the inhibitor of ATP synthase, DCCD. At higher concentrations (6% v/v) ethanol causes stress that slows down culture growth. By monitoring the activity of several respiratory gene promoters in aerobically growing culture under ethanol stress with the green fluorescent protein reporter system, we demonstrate downregulation of these promoters, in particular the ndh promoter. We speculate that the decrease of the respiratory chain activity mitigates the production of reactive oxygen species.

All allergic responses to food indicate failure of immunological tolerance but it is unclear why cow’s milk and egg (CME) allergies resolve more readily than reactivity to peanuts (PN). We sought to identify differences between PN and CME allergies through constitutive immune status and responses to cognate and non-cognate food antigens. Children with confirmed allergy to CME (n=6), PN (n=18) non-allergic (NA) (n=8) controls were studied. Constitutive secretion of cytokines was tested in plasma and unstimulated mononuclear cell (PBMNC) cultures. Blood dendritic cell (DC) subsets were analyzed alongside changes in phenotypes and soluble molecules in allergen stimulated MNC cultures with or without cytokine neutralization. We observed that in allergic children constitutively high plasma levels IL-1β, IL-2, IL-4, IL-5 and IL-10 but less IL-12p70 than in non-allergic children was accompanied by spontaneous secretion of sCD23, IL-1β, IL-2 IL-4, IL-5, IL-10, IL-12p70, IFN- and TNF- in MNC cultures. Furthermore, blood DC subset counts differed in food allergy. Antigen-presenting cell phenotypic abnormalities were accompanied by higher B and T cell percentages with more Bcl-2 within CD69+ subsets. Cells were generally refractory to antigenic stimulation in vitro but IL-4 neutralization led to CD152 downregulation by CD4+ T cells from PN allergic children responding to PN allergens. Canonical discriminant analyses segregated non-allergic and allergic children by their cytokine secretion patterns, revealing differences and areas of overlap between PN and CME allergies. Despite an absence of recent allergen exposure, indication of in vivo activation, in vitro responses independent of challenging antigen and the presence of unusual costimulatory molecules suggest dysregulated immunity in food allergy. Most important, higher Bcl-2 content within key effector cells implies survival advantage with potential to mount abnormal responses that may give rise to the manifestations of allergy. Here, we put forward the hypothesis that the lack of apoptosis of key immune cell types might be central to the development of food allergic reactions.

Pulmonary infections with Mycobacterium avium occur in susceptible individuals following exposure to the bacterium in the environment, where it often persists in biofilms. Many methods have been used to generate biofilms of M. avium, and it is unknown whether different approaches generate similar structures and cell phenotypes. To make a parallel comparison of in vitro biofilm ultrastructure, extracellular matrix (ECM) composition, and drug susceptibility of biofilm resident bacteria, we used two published methods to generate M. avium biofilms: four week incubation in M63 medium or 24 hour exposure to dithiothreitol (DTT). Scanning electron microscopy revealed differences in biofilm ultrastructure between the two methods, including variation in appearance of ECM materials and morphology of resident cells, while light microscopy and staining with calcofluor white indicated that both biofilms contained polysaccharides characteristic of cellulose. Measuring susceptibility of biofilms to degradation by enzymes suggested differences in structurally important ECM molecules, with DTT biofilms having important protein and, to a lesser extent, cellulose components, and M63 biofilms having moderate protein, cellulose, and DNA components. Both biofilms conferred resistance to the bactericidal effects of amikacin and clarithromycin, with resident cells being killed at >10-fold lower rates than planktonic cells at almost all concentrations. Though these comparisons indicate differences in biofilm responses by M. avium under differing conditions, they also suggest common features of biofilm formation including cellulose production and antimicrobial resistance.

Exacerbated inflammatory responses are a hallmark of severe coronavirus disease 2019 (COVID-19). Zileuton (Zi) is a selective inhibitor of 5-lipoxygenase, an enzyme involved in the production of several inflammatory/pro-resolving lipid mediators. Herein, we investigated the effect of Zi treatment in a severe acute respiratory syndrome (SARS) model. Mouse hepatitis virus (MHV)3-infected mice treated with Zi significantly improved the clinical score, weight loss, cardiopulmonary function, and survival rates compared with infected untreated animals. The protection observed in Zi-treated mice was associated with a lower inflammatory score, reduced dendritic cell-producing tumor necrosis factor (TNF), and increased neutrophil-producing interleukin (IL)-10 in the lungs 3 days after infection (dpi). At 5 dpi, the lungs of treated mice showed an increase in Th2-, Treg CD4+-, and Treg CD8+-producing IL-10 and reduced Th1 infiltrating cells. Furthermore, similar results were found upon Zi treatment after SARS-CoV2 infection in transgenic mice expressing the human angiotensin I-converting enzyme 2 (ACE2) receptor driven by the cytokeratin-18 (K18) gene promoter (K18-hACE2), significantly improving the clinical score, weight loss, and lung inflammatory score compared with untreated animals. Our data suggest that Zi protects against developing severe lung disease during SARS induced by betacoronavirus without affecting the host’s capacity to deal with infection.

Systemic autoimmune diseases (SAIDs) such as systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and rheumatoid arthritis (RA) are fully related to the unregulated innate and adaptive immune systems involved in their pathogenesis. They have similar pathogenic characteristics including the interferon signature, loss of tolerance to self-nuclear antigens, and enhanced tissue damage like necrosis and fibrosis. Glucocorticoids and immunosuppressants, which have limited specificity and are prone to tolerance, are used as the first-line therapy. A plethora of novel immunotherapies have been developed including monoclonal and bispecific antibodies, and other biological agents to target cellular and soluble factors involved in disease pathogenesis such as B cells, co-stimulatory molecules, cytokines or their receptors, and signalling molecules. Many of these have shown encouraging results in clinical trials. CAR-T cell therapy is considered the most promising technique for curing autoimmune diseases, with recent successes in the treatment of SLE and SSc.

Here, we found higher percentage of CD8+ T cells in piglets immunized with CVC1302-adjuvanted inactivated FMDV vaccine. We wonder whether promoted cellular immunity induced by CVC1302-adjuvanted inactivated FMDV vaccine due to the promoted antigen cross-presentation efficiency of OVA by DC mainly via the cytosolic pathways, demonstrated by enhanced levels of lysosomal escape of OVA in DC, loaded with OVA and CVC1302. Higher levels of ROS and significant enhanced elevated lysosomal pH in DC facilitated the lysosomal escape of OVA. Significant enhanced CTL activities were observed in mice immunized with OVA-CVC1302. Overall, CVC1302 increased the cross-presentation of exogenous antigens and the cross-priming of CD8+ T cells by alkalizing the lysosomal pH and facilitating the lysosomal escape of antigen. These studies shed new light on the development of immunopotentiators to improve the cellular immunity induced by vaccine.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system caused by myelin-specific autoreactive T cells. We previously demonstrated intestinal barrier disruption and signs of inflammation in experimental autoimmune encephalomyelitis (EAE), a model of MS. Fecal calprotectin is a disease activity biomarker in inflammatory bowel diseases, released by neutrophils in response to inflammation. We aimed to further investigate EAE manifestations in the gastrointestinal tract, and to determine whether calprotectin is a useful biomarker of intestinal inflammation in EAE. Calprotectin was analyzed in feces, cecal contents, and plasma of EAE mice. Infiltrating neutrophils and goblet cells were investigated in different parts of the gastrointestinal tract, before onset of neurological symptoms and during established disease. We found increased calprotectin levels in feces, cecal content and plasma, preceding EAE onset that further escalated during disease progression. Increased neutrophil infiltration in the intestinal tissue concomitant with IL-17 expression and myeloperoxidase activity was found correlating well with clinical activity. Increased goblet cells in intestine similar to irritable bowel syndrome (IBS) were also observed. The results suggest calprotectin as a good biomarker of gastrointestinal inflammation in EAE, also the potential of this model as a useful animal model for IBS.

Coronavirus Disease 2019 (COVID-19) is an infectious respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease, first identified in the Chinese city of Wuhan in November 2019 and has since spread worldwide, is the latest human pandemic, and has officially infected over 800 million people and has caused nearly seven million deaths to date. Although SARS-CoV-2 belongs to the large family of coronaviruses, it has some unique biological characteristics in its interplay with the human host. Therefore, this narrative review aims to provide an up-to-date overview of the structure of the virus, incubation and shedding in the human host, infectivity and biological evolution over time, as well as the main mechanisms for invading human host cells and replicating within. We also proffer that ongoing epidemiological surveillance of newly emerged variants must always be accompanied by biological studies aimed at deciphering new advantageous traits that may contribute to increasing virulence and pathogenicity, such that the most appropriate strategies for establishing a (relatively) safe coexistence with the human host can be implemented.

Auckland Island pigs represent an inbred population of feral pigs isolated on the subantarctic island for over 100 years. The animals have been maintained under pathogen-free conditions in New Zealand, they are well characterized virologically and have been used as donor sources in first clinical trials of porcine neonatal islet cell transplantation for the treatment of human dia-betes patients. The animals do not carry any of the xenotransplantation-relevant viruses and in the first clinical trials no porcine viruses including porcine endogenous retroviruses (PERVs) have been transmitted to the human recipients. PERVs pose a special risk in xenotransplantation since they are part of the pig genome. When the copy number of PERVs in these animals was analyzed using droplet digital PCR, a copy number typical for Western pigs was found, confirming previous phylogenetic analyses of microsatellites and mitochondrial analyses showing a closer relationship to European pigs than to Chinese pigs. When kidney cells from very young piglets were analyzed, only around 20 PERVpol copies were detected. Using these cells as nuclear donors in a somatic cell nuclear transfer (SCNT), animals were born showing PERVpol copy numbers between 35 and 56. This data indicates that Auckland Island pigs have a lower copy number in comparison with other Western pig breeds and that the copy number is higher in adult animals compared with cells from young piglets. Most importantly, PERV-C free animals were selected and the absence of additional eight porcine viruses was demonstrated.

Innate immune pathways play a crucial role in the development of atherosclerosis, from sensing initial danger signals to the long-term reprogramming of immune cells. Despite the success of lipid-lowering therapy, anti-hypertensive medications, and other measures in reducing complications associated with atherosclerosis, cardiovascular disease (CVD) remains the leading cause of death worldwide. Consequently, there is an urgent need to devise innovative preventive and therapeutic strategies to alleviate the global burden of CVD. Extensive experimental research and epidemiological studies have demonstrated the dominant role of innate immune mechanisms in the progression of atherosclerosis. Recently, landmark trials including CANTOS, COLCOT, and LoDoCo2 have provided solid evidence, demonstrating that targeting innate immune pathways can effectively reduce the risk of CVD. These groundbreaking trials mark a significant paradigm shift in the field and open new avenues for atheroprotective treatments. It is therefore crucial to comprehend the intricate interplay between innate immune pathways and atherosclerosis for the development of targeted therapeutic interventions. Additionally, unraveling the mechanisms underlying the long-term reprogramming may offer novel strategies to reverse the pro-inflammatory phenotype of immune cells and restore immune homeostasis in atherosclerosis. In this Review, we present an overview of the innate immune pathways implicated in atherosclerosis, with a specific focus on the signaling pathways driving chronic inflammation in atherosclerosis and the long-term reprogramming of immune cells within the atherosclerotic plaque. Elucidating the molecular mechanisms governing these processes presents exciting opportunities for the development of a new class of immunotherapeutic approaches aimed at reducing inflammation and promoting plaque stability. By addressing these aspects, we can potentially revolutionize the management of atherosclerosis and its associated cardiovascular complications.

A single paragraph of about 200 words maximum. For research articles, abstracts should give a pertinent overview of the work. We strongly encourage authors to use the following style of structured abstracts, but without headings: (1) Background: Place the question addressed in a broad context and highlight the purpose of the study; (2) Methods: briefly describe the main methods or treatments applied; (3) Results: summarize the article’s main findings; (4) Conclusions: indicate the main conclusions or interpretations. The abstract should be an objective representation of the article and it must not contain results that are not presented and substantiated in the main text and should not exaggerate the main conclusions.

Biofilms are complex communities of microorganisms that adhere to surfaces and develop a protective matrix. The colonization of devices in the food and health care industries by microbial biofilms poses numerous risks. Existing antimicrobial agents often fail to penetrate the biofilm matrix, allowing the pathogen to grow and persist. The objective of this study was to evaluate the impact of MADIO PRO+ multipurpose disinfectant on Salmonella Typhimurium biofilm using crystal violet assay and FTIR spectroscopy. Results demonstrated that MADIO PRO+ multipurpose disinfectant significantly (p<0.05) inhibited biomass of S. Typhimurium biofilm and altered the structure of S. Typhimurium biofilm. In conclusion, MADIO PRO+ multipurpose disinfectant offers an advantage in biofilm control strategy. This discovery could help the food and health care industries to plan better microbial intervention strategies.

EGFR tyrosine kinase inhibitors (TKIs) are the preferred initial treatment for non-small cell lung cancer (NSCLC) patients harboring EGFR mutations. However, remission is transient, and no further effective treatment options are available for EGFR-TKI-advanced EGFR-mutant NSCLCs. Immunotherapy with immune checkpoint inhibitors (ICIs) induces sustained cancer remission in a subset of NSCLCs. However, ICI therapy exhibits limited activity in most EGFR-mutant NSCLCs. Mechanistically, the strong oncogenic EGFR signaling in EGFR-mutant NSCLCs contributes to the non-inflamed tumor immune microenvironment (TIME), characterized by a limited number of CD8+ T cell infiltration, a high number of regulatory CD4+ T cells and a high number of inactivated infiltrated T cells. Besides, EGFR-mutant NSCLC patients are generally non-smokers with low levels of PD-L1 expression and tumor mutation burden. However, current understanding only partially explains why a small population of EGFR-mutant NSCLCs durably respond to ICI therapy, resulting in many researchers actively working in this field. This review reviews the hope seen from pre-clinical studies and clinical trials which may be adopted to improve the outcome of ICI therapy in EGFR-mutant NSCLCs. Besides, the underlying mechanisms leading to the inferior clinical outcome of ICI therapy in EGFR-mutant NSCLCs are discussed.

(1) Background: SARS-CoV-2 infection is mostly accompanied by mild COVID-19 symptoms in children. However, the multisystem inflammatory syndrome (MIS-C) and long-term sequelae are often severe complications. Therefore, the protection of the pediatric population against SARS-CoV-2 with effective vaccines is particularly important. Here we compare the humoral and cellular immune responses elicited in children (n=15) aged 5-11 years vaccinated with RBD-based vaccines combined in a heterologous scheme of SOBERANA® 02 and SOBERANA® Plus with those from children (n=10) aged 4-11 years who recovered from mild symptomatic COVID-19. (2) Methods: Blood samples were taken 14 days after last dose for vaccinated and 45-60 days after the infection diagnosis for COVID-19 recovered children. Anti-RBD IgG and ACE2-RBD inhibition were assessed by ELISA; IgA, cytokine and cytotoxic related proteins profile were determined by multiplex assays. Total B and T cell subpopulations and IFN-γ release were measured by multiparametric flow cytometry using a large panel of antibodies after in vitro stimulation with S1 peptides. (3) Results: Significant higher levels of specific anti-RBD IgG and IgA and ACE2-RBD inhibition capacity were found in vaccinated children in comparison to COVID-19 recovered children. Th1-like and Th2-like CD4+ T cells were also significantly higher in vaccinated subjects. IFN-γ secretion were higher in central memory CD4+ T cells of COVID-19 recovered children, but no differences between both groups were found in CD4+ and CD8+ T cells effector, terminal and naïve T cell subpopulations. High levels of IL-2, IL-6, IFN-γ and IL-10 in contrast to low levels of IL-4 suggesting a predominant Th1 cell polarization. Cytotoxic-related proteins granzyme A and B, perforin and granulin were also found in the supernatant after S1 stimulation in both vaccinated and recovered children. (4) Conclusions: Vaccination with the heterologous scheme of SOBERANA® 02/ SOBERANA® Plus induces strong antibody and cellular immune response compared to natural infections of young children.

The newly emerged variants of SARS-CoV-2 created a potential threat among societies and highlighted one of the significant concerns in facing the pandemic. SARS-CoV-2 variants harboring mutations in the structural protein, especially in the RBD domain of spike protein, have raised concern about potential immune escape. The spike protein of SARS-CoV-2 play a vital role in infection and is an important target for neutralizing antibodies. The mutations that occur in the structural proteins, especially in the spike protein, lead to changes in the virus attributes of transmissibility, an increase in disease severity, a notable reduction in neutralizing antibodies generated, and thus a decreased response to vaccines and therapy. The immune response against SARS-CoV-2 has been reported mainly through innate immune responses rather than adaptive immune responses. SARS-CoV-2 invades the host's innate immunity, possibly through inducing cytokine storm, impairing type I IFN responses, and suppressing antigens presentation to T cells. Therefore, the adaptive immune response is required to combat SARS-CoV-2 infection. The SARS-CoV-2 infections activated both arms of adaptive immunity; humoral and cell-mediated immunity. The observed multiple mutations in the RBD domain of the spike protein compromised the adaptive immune response and showed immune escape because it increases the affinity of spike protein binding with the ACE-2 receptor of host cells and increases resistance to neutralizing antibodies. Cytotoxic T-cell responses are crucial in controlling SARS-CoV-2 infections from the infected tissues and clearing them from circulation. CD8+cytotoxic T cells identify and directly kill the infected cells by releasing soluble mediators perforin and granzymes. The functional exhaustion of cytotoxic T cells may increase the severity of the disease. The expression of activation markers of T cells could indicate hyperactivation or functional exhaustion; the exact implication is not yet understood in SARS-CoV-2 infections. These mutations at critical residues influence the antigenic profile of SARS-CoV-2, which may evade the immune responses and thus reduce the immunogenicity and efficacy of vaccines. Therefore, the spike protein may be recognized as a primary target for vaccines and drugs. This review article summarizes the impact of mutations in the spike protein of SARS-CoV-2, especially mutations of RBD, on immunogenicity, immune escape, and vaccine-induced immunity, which could potentially contribute to future studies focusing on vaccine design and immunotherapy.

Conjugative transposons in Gram-negative bacteria have a significant role in the dissemination of antibiotic-resistance-conferring genes between bacteria. This study aims to genomically characterize plasmids and conjugative transposons carrying integrons in clinical isolates of Klebsiella pneumoniae. Genetic composition of conjugative transposons and phenotypic assessment of 50 multidrug-resistant K. pneumoniae isolates from Tertiary-care Hospital (SQUH), Muscat, Oman was investigated. Horizontal transferability was investigated by filter- mating conjugation experiments. Whole genome sequencing (WGS) was performed to determine the sequence type (ST), acquired resistome and plasmidome of integron-carrying strains. Class 1 integron was detected in 96% of isolates and among integron-positive isolates, 18 stains contained variable regions. Horizontal transferability by conjugation confirmed the successful transfer of integrons between cells and WGS confirmed their presence in conjugative plasmids. Dihydrofolate reductase (dfrA14) was the most prevalent (34.8%) gene cassettes in class 1 integrons. MLST analysis detected predominantly ST-231 and ST-395. BlaOXA-232 and blaCTX-M-15 were the most frequently detected carbapenems and beta-lactamases in sequenced isolates. This study highlighted the high transmissibility of MDR-conferring conjugative plasmids in clinical isolates of K. pneumoniae. Therefore, the wise use of antibiotics and the adherence to effective infection control measures are necessary to limit further dissemination of multidrug-resistant organisms.

The collective considerations presented here lead to a crucial question: What truly constitutes the primary public health challenge posed by SARSCoV-2 infection and its variants?The findings of Bowen et al.(1) and Noé et al.(4) have offered us new insights into the actual repercussions of SARSCoV-2 virus infections on public health. They unmistakably point to the late sequelae and complications arising as secondary effects of the viral infection, causing severe and long-term damage to global public health. Rather than the acute infection which has a very low mortality rate in the general population, as initially and commonly believed.

Bacterial resistance to antibiotics is a public health menace that needs urgent efforts to mitigate and forestall their transmission in the general environment. Plasmid-mediated metallo beta-lactamase (MBL) gives bacteria an exceptional ability to transmit resistance genes. This study investigated plasmid-mediated resistance in MBL P. aeruginosa isolates from poultry food chain settings. Cloacal swab samples (n=120) were bacteriologically analyzed for the isolation of P. aeruginosa isolates. Susceptibility studies were performed by the CLSI guideline using selected antibiotics. MBL was phenotypically detected using modified Hodges test, and confirmed using PCR technique. Plasmid curing studies detected the presence of plasmids in the isolates. P. aeruginosa isolates (n=48) showed high levels of reduced susceptibility to cefoxitin (93.8%), imipenem (81.3%), gentamicin (85.4%), amikacin (85.4%), nitrofurantoin (83.3%), ofloxacin (72.9%) and cefotaxime (77.1%). MBL was phenotypically detected in 7 (14%) isolates of P. aeruginosa. The presence of blaIMP-1 and blaIMP-2 MBL genes in P. aeruginosa (n=5) isolates was confirmed by PCR. The PCR did not detect blaVIM-1 and blaVIM-2 MBL genes. The P. aeruginosa isolates were multidrug resistant, with about 50% of the isolates showing multidrug resistance (MDR) to the antibiotics. The genes for MDR in the P. aeruginosa isolates were borne on plasmids, indicating a high possibility of community transmission of MBL resistance genes. Finally, the P. aeruginosa isolates from poultry food chain milieus are multidrug resistant, produce MBL, and harbour their resistance genes on plasmids. Since many antibiotic resistance genes in bacteria are associated with mobile genetic elements (MGEs) like plasmids, it is important to step up actions to mitigate incessant use of antibiotics in poultry and other agricultural practices in Nigeria in order to diminish the evolution and spread of plasmid-mediated resistance which is capable of initiating community acquired infections that may prove difficult to treat in our hospitals with the available antibiotics.

Sporothrix brasiliensis is the most pathogenic species, responsible for the Brazilian cat-transmitted sporotrichosis hyperendemics. In this scenario, investigation of pathogen-host interaction can provide relevant information for future treatment strategies. To this end, the invertebrate Galleria mellonella has proven to be a suitable alternative to evaluate the virulence of pathogenic fungi since the insect immune system is similar to the mammalian innate immune response. The aim of this work was to investigate phenotypic and molecular aspects of the immune response of G. mellonella throughout the S. brasiliensis infection. Hemocyte density and the evolution of the fungal load were evaluated. In parallel, RT- qPCR expression analysis of genes encoding antimicrobial peptides (Gallerimycin and Galiomycin) and stress management genes (C7 Contig 15362 and C8 Contig 1910) was conducted. Fungal load and hemocyte densities were proportionally increasing simultaneously to the deleterious morphological events and larvae mortality. Gallerimycin, C7 Contig 15362, and C8 Contig 19101 genes were positively regulated (p&lt;0.05) at distinct moments of S. brasiliensis infection, characterizing a time-dependent and alternately modulated profile. Galiomycin gene expression remained unchanged. Our results contribute to the future proposal of potential alternative pathways to treat and, consequently, control S. brasiliensis zoonosis, a major public Health in Latin America.

IgY antibodies are found in the blood and yolk of eggs. Several studies show the feasibility of utilising IgY for immunotherapy and immunodiagnosis. These antibodies have been studied because they fulfil the current needs for reducing, replacing, and improving the use of animals. Affinity and avidity represent the strength of the antigen-antibody interaction and directly influence antibody action. The aim of this review was to examine the factors that influence the affinity and avidity of IgY antibodies and the methodologies used to determine these variables. In birds, there are few studies on the maturation of antibody affinity and avidity and these studies suggest that the use of an adjuvant, type of antigen, strain of the animal, number of immunisations, and time interfere with the affinity and avidity of IgY antibodies. Regarding the methodologies, most studies use chaotropic agents to determine the avidity index. Studies involving solution phase and equilibrium titration reactions are also described. These results demonstrate the need for standardisation of methodologies for determination of affinity and avidity so that further studies can be performed to optimise the production of high avidity IgY antibodies.

Streptococcus suis serotype 2 is an important swine bacterial pathogen causing sudden death, septic shock, and meningitis. However, serotype 2 strains are phenotypically and genotypically heterogeneous and composed by a multitude of sequence types (STs) whose distribution greatly varies worldwide. It has been previously shown that lipoprotein (LPP) maturation enzymes diacylglyceryl transferase (Lgt) and signal peptidase (Lsp) significantly modulate the inflammatory host response and play a differential role in virulence depending on the genetic background of the strain. Differently from Eurasian ST1/ST7 strains, the capsular polysaccharide of a North American S. suis serotype 2 ST25 representative strain only partially masks sub-capsular domains and bacterial wall components. Thus, our hypothesis is that since LPPs would be more surface exposed in ST25 strains than in their ST1 or ST7 counterparts, the maturation enzymes would play a more important role in the pathogenesis of the infection caused by the North American strain. Using isogenic Δlgt and Δlsp mutants derived from the wild-type ST25 strain, our studies suggest that these enzymes do not seem to play a role in the interaction between S. suis and epithelial and endothelial cells, regardless the genetics background of the strain used. However, a role in the formation of biofilms (also independently of the STs) has been demonstrated. Moreover, the involvement of LPP dendritic cell activation in vitro seems to be somehow more pronounced with the ST25 strain. Finally, the Lgt enzyme seems to play a more important role in the virulence of the ST25 strain. Although some differences between STs could be observed, our original hypothesis that LPPs would be significantly more important in ST25 strains due to a better bacterial surface exposition could not be confirmed.

Microbes are the most prevalent and widely-distributed life form on planet Earth. They are also cognitive organisms with memory and superior problem-solving skills that use quantum phase transitions during their remarkably-effective gathering and dissemination of information. This narrative review explores the biological ramifications of human holobionts physically embodying the human microbiome and connecting to the Internet of Microbes (IOM) beyond our body. Within the review, we consider: 1) the ways in which our microbial co-partners exerted control over our ancestors and continue to influence our current human generation, 2) how they mold virtually every key aspect of our life and even remain with our body in death and 3) how inward-looking contemplative tools such as meditation and embodied cognition provide an ideal opportunity to connect to the microbial information super highway and tap the full range of human holobiont capacities.

Vaccination has proven highly effective against severe acute res-piratory syndrome coronavirus 2 (SARS-CoV-2), but the long-term immunogenicity and the functional preserved im-mune responses of vaccines are needed to inform evolving evi-dence-based guidelines for boosting schedules. We enrolled 205 healthcare workers into a cohort study; all had received three doses of BBIBP-CorV (China Sinopharm Bio-Beijing Company) inactivated vaccine. We assessed SARS-CoV-2 specific binding antibodies, neutralizing antibody, and peripheral T and B cell responses. We demonstrated that more robust antibody re-sponses to SARS-CoV-2 were elicited by booster immunization compared to primary vaccination. Neutralizing antibody titers to SARS-CoV-2 Omicron variant were also efficiently elevated post homologous vaccine booster despite in a lower titer compared to the prototype stain. In addition to S specific humoral and cellular immunity, BBIBP-CorV also induced N-specific antibody and ef-fector T cell responses. The third-dose vaccination led to further expansion of critical polyfunctional T cell responses, likely an essential element for vaccine protection. In particular, a func-tional role for Tfh cell subsets in immunity was suggested by the correlation between both CD4+Tfh and CD8+Tfh with total anti-body, IgG, B cell responses and neutralizing antibodies. Our study details the humoral and cellular responses generated by the BBIBP-CorV booster vaccination in a seven-month follow up study. There is a clear immunologic boosting value of homolo-gous inactivated SARS-CoV-2 vaccine boosters, a consideration for future vaccine strategies.

Contradictory reports are available on vaccine-associated hyperstimulation of the immune system, provoking the formation of pathological autoantibodies. Despite being interconnected within the same network, the role of the quieter, yet important non-pathological; natural autoantibodies (nAAbs) is less defined. We hypothesize that upon a prompt immunological trigger, also physiological nAAbs exhibit a moderate plasticity. We investigated their inducibility through aged and recent antigenic triggers. Anti-viral antibodies (anti-MMR; n=1739 and anti-SARS-CoV-2 IgG; n=330) and nAAbs (anti-citrate synthase IgG, IgM; n=1739) were measured by in-house and commercial ELISAs, using Croatian (Osijek) anonymous samples with documented vaccination background. Results were subsequently compared for statistical evaluation. Interestingly, IgM isotype nAAb showed a statistically significant connection with anti-MMR IgG seropositivity (p< 0.001 in all cases), while IgG isotype nAAb levels were elevated in association with anti-SARS CoV-2 specific seropositivity (p= 0.019) and in heterogeneous vaccine regimen recipients (unvaccinated controls; vector/mRNA vaccines p= 0.002). Increasing evidence supports the interplay between immune activation and the dynamic expansion of nAAbs. Consequently, further questions may emerge regarding the ability of nAAbs silently shaping the effectiveness of immunization. We suggest re-evaluating the impact of nAAbs on the complex functioning of the immunological network.

The pathogenesis of coronavirus disease 2019 (COVID-19) is associated with a hyperinflammatory response. The mechanisms of SARS-CoV-2-induced inflammation are scantly known. Methylglyoxal (MG) is a glycolysis-derived by-product, endowed with a potent glycating action, leading to the formation of advanced glycation end products (AGEs), the major of which is MG-H1. MG-H1 exerts strong pro-inflammatory effects, frequently mediated by the receptor for AGEs (RAGE). Here, we investigated the involvement of MG-H1/RAGE axis as a potential novel mechanism in SARS-CoV-2-induced inflammation by resorting to human bronchial (BEAS-2B) and alveolar (A549) epithelial cells, expressing different levels of ACE2 receptor (R), exposed to SARS-CoV-2 spike protein 1 (S1). Interestingly, we found in BEAS-2B cells that do not express ACE2-R, that S1 exerted a pro-inflammatory action through a novel MG-H1/RAGE-based pathway. RAGE expression levels in nasopharyngeal swabs from SARS-Cov-2 positive and negative individuals, as well as glyoxalase 1 expression, the major scavenging enzyme of MG, seem to support the results obtained in vitro. Altogether, our findings reveal a novel mechanism involved in the inflammation triggered by S1, paving the way to the study of MG-H1/RAGE inflammatory axis in SARS-CoV-2 infection as a potential therapeutic target to mitigate COVID-19 associated pathogenic inflammation.

Antibiotics have played a crucial role in the reduction of TB incidence globally as evidenced by the fact that before the mid-20th century, the mortality rate within five years of the onset of the disease was 50%. The use of antibiotics has eliminated TB as a devastating disease, but the challenge of resistance to anti-TB drugs, which had already been described at the time of the introduction of streptomycin, has become a major global issue in disease management. Mismanagement of multidrug-resistant tuberculosis (MDR-TB) cases, resulting from intermittent drug use, prescription errors and non-compliance of patients, has been identified as a critical risk factor for the development of extensively drug-resistant tuberculosis (XDR-TB). Antimicrobial resistance (AMR) in TB is a multi-factorial, complex problem of microbes evolving to escape antibiotics, the gradual decline of antibiotic development, and different economic and social conditions. In this review, we summarise recent advances in our understanding of how Mycobacterium tuberculosis evolves drug resistance. We also highlight the importance of developing shorter regimens that rapidly reach bacteria in diverse host environments, eradicating all mycobacterial populations and preventing the evolution of drug resistance. Lastly, we also emphasise that the current burden of this ancient disease is driven by a combination of complex interactions between mycobacterial and host factors, and that only a holistic approach that effectively addresses all the critical issues associated with drug resistance will limit the further spread of drug-resistant strains throught the community.

Natural killer cells are associated with the pathogenesis of ulcerative colitis (UC), but their precise contributions remain unclear. The present study sought to investigate the diagnostic value of activated NK-associated genes (ANAGs) in UC. Bulk RNA-seq and scRNA-seq datasets were obtained from the Gene Expression Omnibus (GEO) and Single Cell Portal (SCP) databases. In the bulk RNA-seq, 92 differentially expressed genes (DEGs) were screened out by the “Batch correction” and “Robust rank aggregation” (RRA) methods. The immune infiltration landscape was estimated by single-sample gene set enrichment analysis (ssGSEA) and CIBERSORT, which revealed a higher abundance of activated NK cells in noninflamed UC tissues. 54 DEGs correlated with activated NK cells were identified as ANAGs. Protein-protein interaction (PPI) analysis and least absolute shrinkage and selection operator (LASSO) regression were utilized to screen out 4 key ANAGs (SELP, TIMP1, MMP7, and ABCG2) and establish an activated NK-associated gene score (ANAG score). The ANAG score demonstrated excellent diagnostic value and was validated in three external datasets. The expression of the 4 key ANAGs was validated in UC patients and healthy controls (HC) samples. Through scRNA-seq data analysis, higher expression levels of SELP, TIMP1, MMP7, and ABCG2 were observed in post-capillary venules, inflammatory fibroblasts, enterocytes, and immature enterocytes. The cell scores based on the ANAGs showed enrichment in endothelial cells and fibroblasts. In conclusion, we established and validated an ANAG score with the ability to precisely diagnose UC. The 4 key ANAGs have the potential to serve as therapeutic targets in UC.

Glucose is an important carbon sources for microbial growth, and its content in infertile soils is essential for the growth of the bacterium. Since the mechanism of oligotrophic bacterium adaptation in barren soils is unclear, the research employed RNA Seq technology to examine the impact of glucose concentration on the low nutrient bacteria BS-G1 in soil affected by desertification. RNA-Seq revealed that differentially expressed genes（DEG）histidine metabolism, glutamate synthesis, HIF-1 signalling pathway, sporulation, and TCA cycle pathway of BS-G1 were significantly enriched in 0.015 g/L glucose concentration, compared with 10 g/L glucose concentration. DEG amino acids system, two-component system, Metal Ion Transport, and nitrogen metabolism system of B. subtilis BS-G1 were significantly enriched in 5 g/L glucose concentration, compared with 10 g/L glucose concentration. In addition, The present study identified its regulation pattern and key genes under the low glucose environment (7 mRNAs, 16 sRNAs). This study primarily investigates the variances in the regulatory pathways of oligotrophic bacteria BS-G1, which holds substantial importance in comprehending the mechanism underlying the limited sugar tolerance of oligotrophic bacteria.

African swine fever (ASF) is a lethal and highly contagious transboundary animal disease with the potential for rapid international spread. Currently, there is no ASF vaccine commercially available. All infected animals must be isolated and culled immediately upon confirmation of the presence of the virus. Works leading to the rational development of protective ASF vaccines are urgently needed. Here, we generated a safe and efficacious live-attenuated vaccine (LAV) VNUA-ASFV-LAVL2 by serial passaging of a field isolate (VNUA-ASFV-05L1, genotype II) in porcine alveolar macrophage (PAMs, 65 passages) and an immortalized porcine alveolar macrophage cell line (3D4/21, 55 passages). VNUA-ASFV-LAVL2 can efficiently replicate in both PAMs and 3D4/21 cells. It provides 100% protection, even with the low dose of 10^2 HAD50, for the vaccinated pigs against the challenge of contemporary pandemic ASFV field isolate. Pigs vaccinated with this LAV at a dose range of 10^2 to 10^5 HAD50 remained clinically healthy during both the 28-day observation period of immunization and the 28-day observation period of challenge. VNUA-ASFV-LAVL2 was completely eliminated from blood by 28 days post inoculation (DPI), and from feces or oral fluids by 17 DPI. It remained a safe, stable, and attenuated phenotype after five passages in pigs. Consistently high levels of ASFV-specific IgG antibodies and significant cellular immunity were detected in vaccinated pigs before the ASFV challenge. These results indicate that the VNUA-ASFV-LAVL2 strain is a safe and efficacious LAV against the genotype II ASFV strain responsible for current ASF outbreaks in Asia.

Macrophages undergo different cellular states upon activation that can be hyporesponsive (tolerated) or hyperresponsive (primed or trained) to subsequent stimuli. Epigenetic modifications are known to play a key role in determining these cellular states. However, little is known about the role of signaling pathways that lead to these epigenetic modifications. Here, we examined the effects of various inhibitors targeting key signaling pathways induced by lipopolysaccharide (LPS) on tolerance and priming in the murine macrophages. We found that a prolonged inhibition (>18 h) of the MEK1/2-ERK signaling axis reversed tolerance and primed cells in expressing IL-1β and other inflammatory cytokines such as IL-6, TNFα, and CXCL10. Ectopic expression of catalytically active and inactive MEK1 mutants suppressed and enhanced IL-1β expression, respectively. Primed cells by the MEK1/2 inhibitor U0126 expressed higher levels of gene sets associated with immune responses and cytokine/chemokine production but lower levels of genes with cell cycle progression, chromosome organization, and heterochromatin formation than non-primed cells. Of interest, expression of the histone 3 lysine 9 (H3K9) methyltransferase Suv39h1 and the H3K9 methylation reader Cbx5 was substantially suppressed, whereas the H3K9 demethylase Kdm7a was enhanced, suggesting a role of the MEK1/2-ERK signaling axis in H3K9 demethylation. The H3K9 trimethylation levels in the genomic regions of IL-1β, TNFα, and CXCL10 were decreased by U0126. Also, the H3K9 methyltransferase inhibitor BIX01294 mimicked and overexpression of Cbx5 prevented the U0126 training effects in both RAW264.7 cells and bone marrow-derived macrophages. Collectively, these data suggest that prolonged inhibition of the MEK1/2-ERK signaling axis reverses tolerance and primed macrophages likely through decreasing H3K9 methylation levels.

The emergence of drug-resistant strains of M. tuberculosis (Mtb) and the phenomenon of phe-notypic tolerance to drugs challenge the goal of tuberculosis (TB) elimination worldwide. By using the ex vivo cultures of alveolar macrophages obtained from lung tissues of TB patients after intensive antimicrobial chemotherapy before surgery, different subpopulations of multi-drug-tolerant Mtb with a spectrum of phenotypic and growth features were identified in the same TB lesions. Our results indicative of not only passive mechanisms generating nonheritable resistance of Mtb to antibiotics, which are associated mainly with a lack of Mtb growth, but also some active mechanisms of Mtb persistence, such as cell wall and metabolic pathway remod-eling. In one of the subpopulations, non-acid-fast Mtb have undergone significant repro-gramming with the restoration of acid-fastness, lipoarabinomannan expression and replication in host cells of some patients after withdrawal of anti-TB drugs. Our data indicate the universal stress protein Rv2623 as a clinically relevant biomarker of Mtb that have lost acid-fastness in human lungs. The studies of Mtb persistence, dormancy, and resumption and the identification of biomarkers characterizing these phenomena are very important to develop vaccines and drug regimens with the individualized management of patients for overcoming the re-sistance/tolerance crisis in anti-TB therapy.

Modulating the gut microbiota with probiotics has been identified as a promising therapeutic method for the management of gastrointestinal illnesses. The effectiveness of probiotics in the treatment of gastrointestinal disorders can only be determined by delving into their underlying mechanisms of action. Through an analysis of the underlying processes, this study hopes to provide light on the potential benefits of probiotics for treating a variety of gastrointestinal conditions. The study covers a wide variety of gastrointestinal conditions, such as IBS, IBD, and antibiotic-associated diarrhea. Modifying the gut microbiota composition, strengthening the gut barrier function, modulating the immune system, and producing beneficial metabolites are among mechanisms of action that have been investigated. The strain- and dose-specific variables essential to getting the best treatment results are also highlighted. This review, which synthesizes the current information, gives a thorough overview of the effectiveness of probiotics in treating a variety of gastrointestinal illnesses and illuminates potential avenues for further study and therapeutic use.

Antibiotics were once called miracle drugs which hit the market with astounding impact as it was considered the ultimate cure for infectious diseases in the mid-20th century. However, today nearly all bacteria that afflict humankind have become resistant to these wonder drugs once developed to stop them, imperilling the foundation of modern medicine. During the COVID pandemic, there was a surge in macrolide use to treat secondary infections and this persistent use of macrolide antibiotics has provoked the emergence of macrolide resistance. In view of the current dearth of new antibiotics in the pipeline, it is essential to find an alternative way to combat drug resistance. Antibiotic potentiators or adjuvants are non-antibacterial active molecules that, when combined with antibiotics, increase their activity. Thus, potentiating the existing antibiotics is one of the promising approaches to tackle and minimize the impact of antimicrobial resistance. Several natural and synthetic compounds have demonstrated effectiveness in potentiating macrolide antibiotics against MDR pathogens. The present review summarizes the different resistance mechanisms adapted by bacteria to resist macrolides and further emphasizes the major macrolide potentiators identified which could serve to revive the antibiotic and can be used for the reversal of macrolide resistance.

Current routine diagnosis of a life-threatening central nervous system (CNS) infections is based on commercial multiplex real-time PCR (RT-PCR) and in-vitro culture investigations, targeting a limited number of pathogens, which requires implementation of a universal diagnosis at the point-of-care laboratory. This study aimed to document a case of non-routinely diagnosed meningoencephalitis in a twelve-year-old patient in Niger Republic. Metagenomic-based on real-time sequencing was applied directly on DNA/RNA extracted from 50 µL leftover CSF sample using Oxford Nanopore MinION, to detect all residual microorganisms non-routinely targeted by RT-PCR panel. In parallel, 1 ng DNA/RNA was used for paired-end Illumina library preparation to confirm the MinION results. Real-time analysis of MinION data detected 132 WU Polyomavirus specific reads after one-hour run. Blast nucleotide of the fasta sequences after assembly of both Illumina and Nanopore reads against NCBI GenBank database identified WU polyomavirus strain W33 (GenBank accession no: GU296367.1). Haemophilus influenzae specific reads (667 reads) were detected which explains the possible co-infection bacteria-DNA virus in this case. Blastn after total reads assembly identified H. influenzae strain PittGG (GenBank accession n° CP000672), belonging to the non-typable H. influenzae genotype by muti-locus-sequence-typing analysis. Furthermore, Achromobacter xylosoxidans (599 reads) were detected in this patient. Based on these findings, we classified this case as polymicrobial meningoencephalitis. Using RT-mNGS, the pathogen genome could be detected directly from a clinical sample, with no specific target. This technique seems to be an adapted method to diagnose non-routinely detectable pathogens, as well as their genotype and antimicrobial susceptibility in reduced time.

Since the onset of the COVID‐19 pandemic, humanity has experienced the spread and circulation of several SARS-CoV-2 variants that differed in transmissibility, contagiousness, and the ability to escape from vaccine-induced neutralizing antibodies. However, issues related to the differences of variant-specific immune responses, remain insufficiently studied. The aim of this study was to compare the parameters of the humoral immune responses in two groups of patients with acute COVID-19 who were infected during the circulation period of the D614G and the Delta variants of SARS-CoV-2. Sera from 48 patients with acute COVID-19 were tested for SARS-CoV-2 binding and neutralizing antibodies using six assays. We found that serum samples from the D614G period demonstrated 3.9‐ and 1.6‐fold increase in RBD- and Spike‐specific IgG binding with Wild type antigens compared with Delta variant antigens (p &lt; 0.01). Cluster analysis showed the existence of two well-separated clusters. The first cluster mainly consisted of D614G period patients and the second cluster predominantly included patients from Delta period. The results thus obtained indicate that humoral immune responses in D614G- and Delta-specific infections can be characterized by variant-specific signatures. This can be taken into account when developing new variant-specific vaccines.

The pathogen Cryptococcus neoformans is a major cause of fungal meningitis in humans. As with other melanotic microorganisms associated with human diseases, the cell wall-associated melanin of C. neoformans is a major virulence factor that contributes to its ability to evade host immune responses. The levels of melanin substrate and the regulation of melanin formation could be influenced by the microbiota-gut-brain axis. Moreover, recent studies show that C. neoformans infection causes dysbiosis in the human gut microbiome. In this review, we discuss the potential association between cryptococcal meningitis and the gut microbiome. Additionally, we emphasize the promising prospects of targeting the gut microbiome as a means of diagnosing and treating this debilitating disease.

Recent years have seen an explosion of interest in the topic of gut health and food, revealing a complex interplay that affects many facets of human health beyond just digestion. This in-depth overview investigates crucial aspects of this connection, illuminating issues including the effects of processed meals, the advantages of fermented foods, individualized diets, and the harmonious relationship between gut bacteria and dietary components. In this article, we'll take a look at how processed foods affect your digestive system, and how their convenience might backfire by upsetting your body's delicate microbial balance. The effects of these diets have been studied, and the results suggest that there may be disruptions in microbial diversity, inflammation, and metabolic health. Instead, fermented foods are explored as potential allies in the fight for gut health. These foods' high probiotic content not only improves digestion and nutrition absorption, but may also have an effect on one's state of mind. There is growing evidence that eating fermented foods can help you maintain a healthy and robust gut microbiome. Recognizing that everyone has a different gut microbiota composition, the idea of individualized nutrition has come to the forefront. One novel strategy for improving digestive health is to provide nutritional advice based on a person's unique microbial profile. This paper looks at how microbiome testing can be combined with professional advice to create food programs that feed specific bacteria communities, improving both diversity and health. In conclusion, this review emphasizes the reciprocal interaction between dietary choices and the gut microbiota, and the significant impact that gut health has on numerous aspects of human health. The more we learn about the complexities of this interplay, the more we can take a holistic approach to nutrition, one that respects the uniqueness of each person's gut microbiome and encourages healthy eating habits. By taking a more all-encompassing view, we are reminded of the critical function of the gut microbiota in determining our health and of the significance of fostering this nuanced symbiotic connection.

Tumor-associated microbiota refers to the community of microorganisms found in tumors and is part of the larger tumor microenvironment (TME). The discovery of the complex relationship between these microbial populations and the growth of cancer has prompted the creation of cutting-edge tailored methods to cancer treatment. In recent years, microbiota profiling's potential as a diagnostic, prognostic, and therapeutic optimization tool has been increasingly apparent. The diagnostic and prognostic use of microbiota profiling is explored in this abstract. Microbiota profiling shows potential for early cancer detection, improved risk stratification, and greater prediction of treatment outcomes by identifying different microbial signatures associated with early-stage tumors, aggressive characteristics, and responses to treatment. In addition, this method provides the way for individualized medicinal approaches based on an individual's specific microbiome.Microbiota profiling is investigated as a means of customizing treatment plans, illuminating how knowledge of an individual's microbiome might direct the development of individualized treatments and multimodal approaches. These kind of interventions have the potential to herald in a new era of patient-centered oncology care by increasing treatment efficacy while decreasing side effects. Despite significant promise, microbiota profiling has obstacles that must be overcome before it can be successfully translated into therapeutic practice. This abstract highlights the revolutionary potential of microbiota-based approaches in cancer care and the need for ongoing research and technology improvements to harness the power of the tumor-associated microbiome for improved patient outcomes.

SARS-CoV-2, the virus that causes theCOVID-19 disease, has been demonstrated to cause immune suppression in certain individuals. This can manifest as a reduced ability for the host's immune system to effectively control the infection. Studies have reported that patients with COVID-19 can exhibit a decline in white blood cell counts, including natural killer cells and T cells, which are integral components of the immune system's response to viral pathogens. These cells play critical roles in the immune response to viral infections, and their depletion can make it harder for the body to mount an effective defense against the virus. Additionally, the virus can also directly infect immune cells, further compromising their ability to function. Some individuals with severe COVID-19 pneumonia may develop a "cytokine storm," an overactive immune response that may result in tissue damage and organ malfunction. The underlying mechanisms of immune suppression in SARS-CoV-2 are not entirely comprehended at this time, and ongoing research is being conducted to gain a more comprehensive understanding. Research has shown that severe SARS-CoV-2 infection promotes the synthesis of IgG4 antibodies. In this work, we propose the hypothesis that the IgG4 antibody produced by B cells in response to infection by SARS-CoV2 generates immunological tolerance that prevents its elimination, and leads to persistence and chronic infection. In sum, we believe that this constitutes another immune evasion mechanism that bears striking similarities to that developed by cancer cells to evade immune surveillance.

COVID-19 is characterized by a heterogeneous clinical presentation and prognosis. Risk factors contributing to the development of severe disease include old age and the presence of comorbidities. However, the genetic background of the host has also been recognized as an important determinant of disease prognosis. Considering the pivotal role of innate immunity in the control of SARS-CoV-2 infection, we analyzed the possible contribution of several innate immune gene polymorphisms (including TLR2-rs5743708, TLR4-rs4986790, TLR4-rs4986791, CD14-rs2569190, CARD8-rs1834481, IL18-rs2043211 and CD40-rs1883832) in disease severity and prognosis. A total of 249 individuals were enrolled and further divided into five (5) groups, according to the clinical progression scale provided by the World Health Organization (WHO) (asymptomatic, mild, moderate, severe and critical). We identified that elderly patients with obesity and/or diabetes mellitus were more susceptible to developing pneumonia and respiratory distress syndrome after SARS-CoV-2 infection, while the IL18-rs1834481 polymorphism was an independent risk factor for developing pneumonia. Moreover, individuals carrying either the TLR2-rs5743708 or the TLR4-rs4986791 polymorphisms exhibited a 3.6- and 2.5-fold increased probability for developing pneumonia and a more severe disease, respectively. Our data supports the notion that the host’s genetic background can significantly affect COVID-19 clinical phenotype, also suggesting that the IL18-rs1834481, TLR2-rs5743708 and TLR4-rs4986791 polymorphisms may be used as molecular predictors of COVID-19 clinical phenotype.

Bone Morphogenetic Proteins (BMPs) are a group of structurally and functionally related signaling molecules that comprise a subfamily, belonging to the TGF-β superfamily. Most BMPs play roles in the regulation of embryonic development, stem cell differentiation, tumor growth and some cardiovascular and cerebrovascular diseases. Although evidences are emerging for the antiviral immunity of a few BMPs, more BMPs are needed to determine whether this function is universal. Here we identified the zebrafish bmp4 ortholog, whose expression is up-regulated by challenge with virus or its mimic poly(I:C). Overexpression of bmp4 in EPC cells significantly decreased the viral titer of GCRV-infected cells. Moreover, compared to wild type zebrafish, viral load and mortality were significantly increased in both larvae and adults of bmp4-/- mutant zebrafish infected with GCRV virus. We further demonstrated that Bmp4 promotes the phosphorylation of Tbk1 and Irf3 through p38 MAPK pathway, thereby inducing the production of type I IFNs in response to virus infection. These data suggest that Bmp4 runs an important role in the host defense against virus infection. Our study expands the understanding of BMP protein functions and opens up new targets for the control of viral infection.

Immunological aging type definition requires establishing reference intervals from the distribution of immunosenescence biomarkers conditional on age. For 1,605 individuals (18–97 years), we determined the comprehensive IMMmune Age indeX IMMAX from flow cytometry-based blood cell sub-populations, and identified age-specific centiles by fitting generalized additive models for location, scale and shape. The centiles were uncorrelated with age, and facilitated the categorization of individuals as immunologically slow or fast aging types. Using its 50th percentile as reference, we rescaled IMMAX to equivalent years-of-life (EYOL), and computed the immunological age gap as difference between EYOL and chronological age. Applied to preliminary baseline and follow-up measurements from 53 participants of the Dortmund Vital Study (Clinical-Trials.gov Identifier: NCT05155397), the averaged changes in IMMAX and EYOL conformed to the 5-year follow-up period, whereas no significant changes occurred concerning IMMAX centiles and age gap. This suggested that the participants immunologically adapted to aging, and kept their relative positions within the cohort. Sex was non-significant. Methodical comparisons indicated that future confirmatory analyses with the completed follow-up examinations could rely on percentile curves estimated by simple linear quantile regression, while the selection of the immunosenescence biomarker will greatly influence the outcome, with IMMAX representing the preferable choice.

Lactic acid bacteria (LAB) have an extracellular proteolytic system that includes a multi-domain, cell envelope protease (CEP) with a subtilisin homologous protease domain. These CEPs have different proteolytic activities despite having similar protein sequences. Structural characterization has previously been limited to CEP homologs of dairy and human derived LAB strains, excluding CEPs of plant derived LAB strains. CEP structures are a challenge to determine experimentally due to their large size and attachment to the cell envelope. This study aims to clarify the prevalence and structural diversity of CEPs by using the structure prediction software AlphaFold 2. Domain boundaries are clarified based on a comparative analysis of 21 three-dimensional structures, revealing novel domain architectures of CEP homologs that are not necessarily restricted to specific LAB species or ecological niches. The C-terminal flanking region of the protease domain is divided into fibronectin type-III-like domains with various structural traits. The analysis also emphasizes the existence of two distinct domains for cell envelope attachment that are preceded by an intrinsically disordered cell wall spanning domain. The domain variants and their combinations provide CEPs with different stability, proteolytic activity and potentially adhesive properties, making CEPs targets for steering proteolytic activity with relevance for both food development and human health.

There is a growing body of evidence supporting the significant role of bacterial biofilms in the pathogenesis of various human diseases including cancer. Biofilms are polymicrobial communities enclosed within an extracellular matrix composed of polysaccharides, proteins, extracellular DNA, and lipids. This complex matrix provides protection against antibiotics and host immune responses, enabling the microorganisms to establish persistent infections. Moreover, biofilms induce anti-inflammatory responses and metabolic changes in the host, further facilitating their survival. Many of these changes are comparable to those observed in cancer cells. This review will cover recent research on the role of bacterial biofilms in carcinogenesis, especially in colorectal (CRC) and gastric cancers, emphasizing the shared physical and chemical characteristics of biofilms and cancer. This review will also discuss the interactions between bacteria and the tumor microenvironment, which can facilitate oncogene expression and cancer progression. This information will provide insight into developing new therapies to identify and treat biofilm-associated cancers, such as utilizing bacteria as delivery vectors, using bacteria to upregulate immune function, or more selectively targeting biofilms and cancer for their shared traits.

Vibrio splendidus is the main pathogen infect a wide range of hosts, especially sea cucumber Apostichopus japonicus. Our previous studies had shown that the level of L-glutamic acid (L-Glu) was significantly increased under heat stress and it was one of the best carbon sources that could be used by V. splendidus AJ01. In this study, the effects of exogenous L-Glu on the coelomocyte viability, tissue status and individual mortality of sea cucumbers were analyzed. The results showed that 10 mM L-Glu decreased coelomocyte viability and increased mortality, with tissue rupture and pyknosis, while 0.1 mM L-Glu slightly affected the survival of sea cucumbers without obvious damages at both cellular and tissue levels. Transcriptomic analysis showed that there were 343 upregulated and 206 downregulated genes regulated by exogenous L-Glu. GO analysis showed that differentially expressed genes (DEGs) were mainly enriched in signaling and membrane formation, while KEGG analysis showed that DEGs were significantly enriched in the upregulated endocytosis and downregulated lysosomal pathways. The coelomocyte viability further decreased 20% in the simultaneous presence of exogenous L-Glu and V. splendidus AJ01, compared to that of V. splendidus AJ01 infection alone. Consequently, a higher mortality of sea cucumber was also observed in the presence of exogenous L-Glu challenged by V. splendidus AJ01. Real time reverse transcriptase PCR showed that L-Glu specifically upregulated the expression of the fliC gene, conding the subunit protein of flagellar filament, with promoted swimming motility activity of V. splendidus. Our result indicated that L-Glu should be kept in a state of equilibrium, and the excess L-Glu in the host-pathogen interface would prompt the virulence of V. splendidus via increasing bacterial motility.

Maternal milk supports offspring development by providing microbiota, macronutrients, micronutrients, immune factors, and hormones. The hormone prolactin (PRL) is an important component of milk with protective effects against chronic non-communicable diseases (NCDs). Because maternal milk regulates microbiota composition and microbiota protect against NCDs, we aimed to investigate whether PRL regulates gut microbiota in newborn mice. 16SrRNA sequencing of feces and bioinformatics analysis were performed to evaluate gut microbiota in mice null for the PRL receptor (Prlr-KO) at the onset of weaning (postnatal day 21). The normalized colon and cecal weights were higher and lower, respectively, in Prlr-KO mice relative to wild-type mice (Prlr-WT). Relative abundance (Simpson Evenness Index), phylogenetic diversity, and bacterial concentration in gut contents were lower in the absence of the PRL receptor. Eleven bacteria species, out of 470, differed between Prlr-KO and Prlr-WT mice with two bacterial genera (Anaerotruncus and Lachnospiraceae) related to NCD development being the most common in Prlr-KO. Furthermore, a higher metabolism of terpenoids and polyketides was predicted in Prlr-KO mice compared to Prlr-WT mice; these metabolites have antimicrobial properties and are present in microbe-associated pathogenicity. In summary, the absence of the PRL receptor changes intestinal microbiota composition, resulting in lower microbiota abundance and richness, which could contribute to NCD development.

In rice, symbiotic N fixation via nodule bacteroids does not take place naturally. Although N fixation by endophytic and associative diazotrophs has been reported in rice, main organs and seasonal regulation for the N fixation have not been elucidated. In this study, therefore, seasonal changes of nitrogenase (acetylene reduction) activity and carbohydrate contents in culm internode (IN), basal nodes (BN), and crown root (CR) were investigated in manure compost (MC)- and chemical fertilizer-applied rice. Nitrogenase activity increased after rooting, and reached the highest activity in BN of MC-applied rice at panicle initiation. In BN of MC-applied rice, the sucrose content was low whereas the higher glucose content was detected at panicle initiation. Although bacterial and diazotrophic bacterial populations were most abundant in CR, the nitrogenase activity seemed to be restricted by its trace sucrose and glucose contents. In addition, alpha-Proteobacteria and Clostridia phyla were abundant in BN-specific bacterial microbiota at panicle initiation. These results suggest that the increased N fixation in BN at panicle initiation might be sustained both by the non-structural carbohydrate supply from photosynthetic apparatus and BN-specific bacterial microbiota including diazotrophs.

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 enters the host by infecting nasal ciliated cells. Then, the virus can spread towards the oropharyngeal cavity and the pulmonary tissues. The antiviral adaptive immunity is promptly induced in response to virus detection, with virus-specific T lymphocytes appearing before antiviral antibodies. Both breadth and potency of the antiviral CD8+ T cell immunity have a key role in containing viral spread and disease severity. Current anti-SARS-CoV-2 vaccines do not impede the virus replication in the upper respiratory tract, and there is consensus on the fact that the best potency of the antiviral immune response in both blood and upper respiratory tract can be reached upon infection in vaccinees (i.e., breakthrough infection). However, whether the antiviral CD8+ T cells developing in response to the breakthrough infection in the upper respiratory tract diffuse to the lungs also is still largely unknown. To fill the gap, we checked the CD8+ T cell immunity elicited after infection of K18-hACE2 transgenic mice both 3 weeks and 3 months after anti-Spike vaccination. The virus-specific CD8+ T cell immunity was monitored in both blood and the lungs before and after infection. By investigating the de novo generation of CD8+ T cells specific for SARS-CoV-2 viral proteins, we found that both membrane (M) and/or nucleocapsid (N)-specific CD8+ T cells were induced at comparable levels in blood of both unvaccinated and vaccinated mice. Conversely, N-specific CD8+ T cells were readily found in the lungs of control mice, but were either rare or absent in those of vaccinated mice. These results support the idea that the hybrid cell immunity developing after asymptomatic/mild breakthrough infection strengthens the antiviral cell immunity at lungs only marginally, implying that the direct exposition of the viral antigens is required for the induction of an efficient antiviral cell immunity in the lungs.

CD4+ T cells orchestrate and regulate immunity within jawed vertebrates, yet our understanding of their evolution, development, and cellular physiology has only begun to be unearthed in the past few decades. Discoveries of genetic diseases that ablate this cellular population have provided insight into their critical functions while transcriptomics, proteomics, and highresolution microscopy have recently revealed new insights into CD4+ T cell anatomy and physiology. This article compiles historical, microscopic, and multi omics data which can be used as a reference atlas to dissect cellular physiology within these influential cells and further understand pathologies like HIV infection that inflict human CD4+ T cells.

Multidrug-resistant (MDR) Pseudomonas aeruginosa infections represent major a public health concern and require comprehensive understanding of their genetic make-up. This study investigated the first occurrence of IMP-carrying MDR P. aeruginosa strains from Bulgaria. Whole genome sequencing identified a novel plasmid-mediated blaIMP-100 allele located in a In1300-like integron embedded in a novel putative transposon. Two other closely related chromosomal blaIMP variants IMP-13 and IMP-84 were also detected. The IMP-producers were resistant to last-line drugs including cefiderocol (CFDC) (2 out of 3) and susceptible to colistin. The blaIMP-13/84 cassettes were situated in a In320 integron inserted in a Tn5051-like transposon as previously reported. Lastly, the p47825-IMP plasmid rendered PAO1 transformant resistant to CFDC, suggesting a transferable CFDC resistance. A variety of virulence factors associated with adhesion, antiphagocytosis, iron uptake, quorum-sensing, as well as secretion systems, toxins, and proteases were confirmed, suggesting significant pathogenic potential consistent with the observed strong biofilm formation. Emergence of IMP-producing MDR P. aeruginosa is alarming as they remain unsusceptible even to last geneneration drugs like CFDC. Newly detected IMP-100 was even located in an CFDC-resistant XDR strain.

The COVID-19 pandemic cost 7-8 million deaths worldwide, creating an unprecedented health and economic crisis. Affecting 700 million people globally, the magnitude of this pandemic is far from anything that humanity has encountered in recent times. A detailed investigation revealed that more than the SARS-CoV2 virus, the hyperactive immune system mediated injury as the real cause of mortality. Cytokine storm following viral infection leads to the surge of proinflammatory cytokines resulting in ARDS and lung injury. Anti-inflammatory intervention with anti-IL6 (anti-IL-6 receptor monoclonal antibodies (mAbs) (e.g., sarilumab, tocilizumab) and anti-IL-6 mAbs (i.e., siltuximab) and /or steroid-based approach lead to substantial protection and prevent death thereby implying the role of inflammation in COVID-19. In this short review, we summarized the dysregulated immune system in COVID-19 infection, investigating in detail the virus–host immune cross talks and presenting the possibilities of therapeutic intervention.

Sclerotinia sclerotiorum is a devastating fungal pathogen that causes severe crop losses worldwide. It is of vital importance to understand its pathogenic mechanism for disease control. Through a forward genetic screen combined with next-generation sequencing, a putative protein kinase, SsCak1, was found to be involved in growth and pathogenicity of S. sclerotiorum. Knockout and complementation experiments confirmed that deletions in SsCAK1 caused defects in mycelium and sclerotia development, as well as appressoria formation and host penetration, leading to complete loss of virulence. These findings suggest that SsCak1 is essential for growth, development and pathogenicity of S. sclerotiorum. Therefore, SsCak1 could serve as a potential target for the control of S. sclerotiorum infection through host-induced gene silencing (HIGS), which could increase crop resistance to the pathogen.

The body's billions of bacteria—the microbiota—influence health and illness. The microbiome—the genetic material of these microbes—affects digestion, immunological function, and mental health. Due to bacterial variety, complicated relationships, and research technique constraints, investigating the microbiota is difficult. AI and machine learning have expanded microbiome research. Artificial intelligence (AI) systems can efficiently scan large microbiome datasets to help researchers understand microbial populations and their functions. AI-based predictive algorithms can analyze food impacts on microbial communities and forecast illness risks based on gut microbiota composition. AI helps find microbial biomarkers linked to specific health disorders, enabling early illness identification and targeted therapy. AI-driven medication development platforms also modulate microbiome to treat microbiota-related diseases. Understanding microbial populations' involvement in health and illness requires understanding complicated microbial interactions within the microbiome and between it and the host. AI systems improve human health by comprehending these complex relationships. AI in microbiota study must overcome various obstacles. Data quality and AI model interpretability are essential for accurate findings. Diverse and representative datasets avoid biases and strengthen AI-driven conclusions. AI in microbiota research requires data protection, informed permission, and appropriate use of sensitive data. AI is improving our understanding of the human microbiome and its health effects, changing microbiota research. Overcoming difficulties and adhering to ethical norms will enable the proper use of AI-driven findings, leading to microbiome insights and precision medical breakthroughs.

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by a defect in the phagocytic function of the innate immune system owing to mutations in genes encoding the five subunits of the nicotinamide adenine dinucleotide (NADPH) oxidase enzyme complex. This review aimed to provide a comprehensive approach to the pathogens associated with chronic granulomatous disease (CGD) and its management. The topics covered included common pathogens infecting CGD patients, granulomas, and CGD-related infectious diseases, including invasive aspergillosis, Mulch pneumonitis, and liver abscesses. In addition, we also covered the differential diagnosis of CGD and its management. Patients with CGD, often children, have recurrent life-threatening infections and may develop infectious or inflammatory complications. The most common microorganisms observed in the patients with CGD are Staphylococcus aureus, Aspergillus spp, Candida spp, Nocardia spp, Burkholderia spp, Serratia spp, and Salmonella spp. Triple-dose antimicrobial prophylaxis with empiric regimens is recommended. Therefore, therapeutics against this disease must be optimised, considering the lack of curative therapies and the long-term side effects of prophylactic regimens. Consequently, allogeneic haematopoietic stem cell transplantation from a human leukocyte antigen-identical donor has been proven to cure CGD.

Antimicrobial peptides (AMPs) can directly kill Gram-positive bacteria, Gram-negative bacteria, mycobacteria, fungi, enveloped viruses and parasites. At sublethal concentrations some AMPs and also conventional antibiotics can stimulate bacteria response to increase their resilience, also called the hormetic response. That can include stimulation of growth, mobility, and biofilm production. Here, we have discovered AMPs that stimulate the growth of certain mycobacteria. Peptide 14 for example showed growth stimulating effect on M. tuberculosis, M. bovis, M. avium subsp. paratuberculosis (MAP), M. marinum, M. avium-intracellulare, M. celatum and M. abscessus. The effect was more pronounced at low bacterial inocula. The peptides induce a faster transition from the lag phase to the log phase and keep the bacteria longer in the log phase before entering the stationary phase compared to non treated control. In some cases, an increase in the division rate was observed. An initial screen using MAP and a collection of 75 peptides revealed 13 peptides with a hormetic effect. For M. tuberculosis a collection of 25 artificial peptides were screened and 9 were found to reduce the time to positivity (TTP), improving growth. A screen of 43 naturally occurring peptides, 11 fragments of naturally occurring peptides and 5 designed peptides, all taken from the APD3, identified a further 44 peptides that also lowered TTP by at least 5%. Lasioglossin LL-III (Bee) and Ranacyclin E (Frog) were the most active natural peptides, the human cathelicidin LL37 fragment GF-17 and a porcine cathelicidin protegrin-1 fragment was the most active fragment of naturally occurring peptides. Peptide 14 showed growth-stimulating activity between 50 ng/ml and 10 µg/ml whereas the stability-optimised peptide 14D had a narrow activity range of 0.1 - 1 µg/ml. Peptides identified in this study are now part of novel products improving the diagnosis of mycobacteria in humans and animals.

The dimorphic, soil-dwelling fungus Coccidioides is the causative agent of coccidioidomycosis and is a reemerging pathogen of human health concern. Despite increasing incidence and isolations of the organism outside of its theoretical environmental range, much of Coccidioides epidemiology, including complete host range, remains unknown. Feral swine (Sus scrofa) are an invasive species distributed throughout the United States that may play a role in fungal ecology due to their behavioral associations with soil. To address this, we evaluated seven feral swine for susceptibility to Coccidioides. After intranasal inoculation with 106.2 arthroconidia of C. posadasii, no pigs displayed signs of clinical disease, nor did any exhibit antibodies by AGID testing. Histopathologic evaluation did not reveal the presence granulomatous lesions, and fungal spherules or endospores were not observed in any of the tissue sections examined, although individuals had significant comorbidities, most notably Metastrongylus nematodes in the lungs. Despite the absence of lesions and organisms histologically, C. posadasii was isolated by culture from the lung and mediastinal lymph node of two pigs, indicating active infection. These results suggest that feral swine are mildly susceptible to acute Coccidioides infection and may aid in fungal dispersal due to the presence of spherules in tissues post-mortem.

Background: Post-delivery period could be characterized by psychological distress (e.g., anxiety, sadness, and irritability), leading to post-partum depression (PPD). Objective: The present clinical study assess the effect of probiotic supplementation containing Limosilactobacillus reuteri PBS072 and Bifidobacterium breve BB077 (4x10⁹ CFU/day) on mother’s mood and breastfeeding quality during the first trimester after delivery. Methods: A Randomized Double Blind Controlled (RDBPC) trial has been carried out in 200 healthy new mothers divided into an active group taking a supplement containing Limosilactobacillus reuteri PBS072 and Bifidobacterium breve BB077 (4x10⁹ CFU/day) plus multivitamins, and a control group (multivitamin complex only) for 90 days. Symptoms related to maternal depression and breastfeeding quality were evaluated at days 45 and 90 by Edinburgh Postnatal Depression Scale (EPDS) and Breastfeeding Self-Efficacy Scale Short-Form (BSES-SF). Results: At days 45 and 90, probiotic treatment significantly ameliorated the mothers’ mood compared to the control treatment (p<0.001). Likewise, breastfeeding quality and baby’s cries significantly improved in the probiotic group (p<0.001). Conclusions: Microbiota alterations could influence post-delivery woman’s mental state. According to our results, L. reuteri PBS072 and B. breve BB077 are potential candidates able to improve stress resilience in the post-partum period.

Round bodies in spirochete cultures have been a controversial subject since their description seven decades ago. We report the existence of round bodies (spherical cells) in cultures of Mucispirillum schaedleri, a spiral bacterium phylogenetically distant from spirochetes. Furthermore, when grown in biofilms, M. schaedleri demonstrates a unique morphology known as cording, which has been previously described only in mycobacteria. Thus, M. schaedleri has two distinct features, each previously thought to be unique to two different phylogenetically distant groups of bacteria.

Like other organisms, fungi produce extracellular vesicles (EVs) that are involved in various biological processes, including intercellular communication and the transport of molecules between cells. These EVs can be applied in fungal pathogenesis, virulence, and interactions with other organisms, including host cells, in the case of fungal infections. While some types of mycoses are relatively common and easily treatable, certain neglected mycoses pose significant public health challenges, such as sporotrichosis, chromoblastomycosis, and paracoccidioidomycosis. These infectious diseases can cause significant morbidity and disability, leading to a reduced quality of life for the patients. So, research about the virulence factor is essential to understand how fungi escape the immune system. In this context, this manuscript reviews the study of fungi EVs, their cargo, their obtaining, and their role during the infectious process, which is extremely important for understanding this neglected mycosis.

The gut microbiota's part in colon cancer has become an exciting and hopeful area of study because it shows complex links that affect how cancer starts, spreads, and responds to treatments. Dysbiosis, which is an imbalance in the community of germs in the gut, has been linked to a higher risk of colon cancer by causing inflammation and making a place where tumours can grow. Researchers have found that some kinds of bugs can either help colon cancer grow or stop it from doing so. This shows how important it is to maintain a healthy gut bacteria. In both preclinical and clinical research, therapeutic treatments that target the microbiome in the gut have shown promise. Probiotics and prebiotics can change the environment around a tumour, change the balance of microorganisms in the gut, and boost immune responses that fight the cancer. Faecal microbiota transfer (FMT) is being looked at as a new way to change the bacteria in the guts of people with colon cancer. By adding microbiota-targeted drugs to standard cancer treatments, it may be possible to make the treatment more effective and lessen side effects. Microbiota-focused treatments for colon cancer are still in their early stages, but they show promise. More research needs to be done to find out how they work and show that they work in the clinic. The link between the bacteria in the gut and colon cancer opens up new ways to help patients and give them better results. This might make a difference in how colon cancer is handled in the future.

Leptospirosis is a zoonotic disease of global importance. The current killed vaccine provides serovar-specific protection without sterilizing immunity. Several surface antigens, including Leptospira immunoglobulin-like proteins (LigA and LigB), have been identified as subunit vaccine candidates; however, they require potent adjuvants. Bacterial Lipopolysaccharide (LPS), including lipid A, is a well-known immunostimulatory agent, and the formulation of Monophosphoryl Lipid A (MPLA) in Alum is a clinical adjuvant. Being less endotoxic, we tested the adjuvant activity of lipid A purified from L. interrogans serovar Pomona (PLA) for its ability to activate innate and enhance antigen-specific adaptive immune response. PLA-induced activation of macrophages similar to levels induced by MPLA, albeit at a much higher dose, indicating that it is less stimulatory than MPLA. Mice immunized with a Variable portion of LigA (LAV) formulated in Alum and PLA (LAV-Alum-PLA) induced significantly higher levels of LAV-specific humoral and cellular immune response than Alum but similar to levels induced by Alum-MPLA. The adjuvant activity of PLA seems to be quite similar to MPLA and primarily mediated through enhanced recruitment, activation, and uptake of antigens by innate immune cells. Moreover, like MPLA, the PLA formulation was able to generate a long-term memory response. Most importantly, PLA demonstrated better potency than MPLA formulation and generated sterilizing immunity against challenge in a hamster model of leptospirosis. Altogether, our study has provided important insight into the adjuvant activity of Leptospira lipid A and has opened avenues for the development of LPS-based vaccines against this dreadful zoonosis.

The DnaA protein has long been considered to play the key role in the initiation of chromosome replication in modern bacteria. Many questions about this role, however, remain unanswered. Here, we raise these questions within a framework based on the dynamics of hyperstructures alias large assemblies of molecules and macromolecules that perform a function. In this dynamics, hyperstructures can (1) emit and receive signals or (2) fuse and separate from one another. We ask whether the DnaA-based initiation hyperstructure acts as a logic gate receiving information from the membrane, the chromosome and metabolism to trigger replication; we try to phrase some of these questions in terms of DNA supercoiling, strand opening, glycolytic enzymes, SeqA, ribonucleotide reductase, the Macromolecular Synthesis operon, post-translational modifications and metabolic pools. Finally, we ask whether, underpinning the regulation of the cell cycle, there is a physico-chemical clock inherited from the first protocells, and whether this clock emits a single signal that triggers both chromosome replication and cell division.

Obesity and metabolic syndrome involve chronic low-grade inflammation called metabolic inflammation as well as metabolic derangements from increased endotoxin and free fatty acids. It is debated whether the endoplasmic reticulum (ER) stress in monocytic cells can contribute to amplify metabolic inflammation; if so, by which mechanism(s). To test this, metabolic stress was induced in THP-1 monocytic cells by treatments with lipopolysaccharide (LPS), palmitic acid (PA), or oleic acid (OA), in the presence or absence of ER stressor thapsigargin (TG). Gene expression of tumor necrosis factor (TNF)-α and markers of ER/oxidative stress was determined by qRT-PCR, TNF-α protein by ELISA, ROS by DCFH-DA assay, HIF-1α/p38/ERK-1,2/NF-κB phosphorylation by immunoblotting, and insulin sensitivity by glucose-uptake assay. Regarding clinical analyses, adipose TNF-α was assessed by qRT-PCR/IHC and plasma TNF-α/hs-CRP/MDA/OX-LDL by ELISA. We found that the cooperative interaction between metabolic and ER stresses promoted TNF-α, ROS, CHOP, ATF6, SOD2, and NRF2 expression (P≤0.0183),. However, glucose uptake was not impaired. TNF-α amplification was dependent on HIF-1α/p38/NF-κB phosphorylation, while MAPK/NF-κB inhibitors and antioxidants/ROS scavengers attenuated TNF-α production (P≤0.05). Individuals with obesity displayed increased adipose TNF-α gene/protein expression as well as elevated plasma levels of TNF-α, CRP, MDA, and OX-LDL (P≤0.05). Our findings support a cooperative interaction between metabolic and ER stresses, favoring inflammation by triggering TNF-α production via the ROS/CHOP/HIF-1α and MAPK/NF-κB dependent mechanisms. This study also shows the therapeutic potential of ROS scavengers/anti-oxidants in inflammatory conditions involving metabolic/ER stresses.

The microenvironment of most tumors is complex, comprising numerous aspects of immunosuppression. Several studies have indicated that the adrenergic system is vital for controlling immunological responses. In the context of tumor microenvironment, Nor-Adrenaline (NA) is poured-in by innervating nerves and tumor tissues itself. The receptors for nor-adrenaline are present on the surface of cancer and immune cells and are often involved in activation of pro-tumoral signaling pathways. β2-adrenergic receptor (β2-AR) is an emerging class of receptors that are capable of modulating the functioning of immune cells. β2-AR is reported to activate the regulatory immune cells and inhibit the effector immune cells. Blocking β2-AR increases activation, proliferation and cytokine release of T lymphocytes. Moreover β2-AR deficiency during metabolic reprograming of T cells increases mitochondrial membrane potential and biogenesis. In the view of available research data, immunosuppressive role of β2-AR in T cells presents it a targetable checkpoint in CAR-T cell therapies. In this review, we have abridged contemporary knowledge about adrenergic stress mediated β2-AR activation on T lymphocytes inside tumor milieu.

The trillions of bacteria that live in and on our bodies make up the human microbiota, which is a very important part of keeping us healthy and protecting us from pathogenic infections. Dysbiosis is when there are changes in the composition and variety of the microbiota. This can upset the delicate balance between the host and its microbes, making the host more vulnerable to pathogens. Understanding the complicated link between microbiota and pathogens is important for coming up with effective ways to change microbiota and boost the body's defenses against infections. This study looks at how microbiota modulation affects the spread of pathogens and infections. It talks about how the makeup of microbiota affects how susceptible you are to pathogens. It shows how a healthy microbiota can protect you by making it hard for pathogens to grow and take over. The review also goes into detail about how the microbiota protects against pathogens, such as through competitive exclusion, the production of antimicrobial compounds, and the regulation of immune reactions. The study also looks at the idea of dysbiosis and how it is linked to pathogenic shifts. Disruptions in the microbiota can make it easier for pathogens to grow and make it harder for the host to fight off infections. It focuses on the need to recover microbial balance to improve the host's defenses and lower risks caused by pathogens. There is also talk about the use of probiotics, prebiotics, and fecal microbiota transplantation (FMT) as ways to change the microbiome. The goal of these interventions is to restore the diversity and function of microbes, improve the integrity of barriers, and boost the immune system's reaction to pathogens. The review shows how these methods could be used to change the microbiota and make it easier for the body to fight off infections. In conclusion, knowing how the microbiota and pathogens work together in a complicated way can help a lot when it comes to making specific interventions for microbiota modulation. Strategies that restore the balance of microbes and boost the host's defenses could stop pathogens from taking over and making people sick. More study needs to be done in this area to improve therapeutic approaches and use the microbiota to its fullest extent to fight infectious diseases.

Probiotics have become a potential way to change the microbiota, which allows for more personalized ways to improve health results. This abstract gives an outline of the most important parts of personalized microbiota regulation through probiotics. It focuses on effectiveness and mechanisms, clinical applications, safety and tolerability, formulations and delivery methods, and customized approaches. Many studies have looked into how and why probiotics change the microbiome. These studies show that probiotics can change the makeup and function of microbial communities. Probiotics have been shown to help treat a number of health problems, such as digestive problems, immune system problems, metabolic problems, and mental health problems. It is important for the success of probiotics to find out if they are safe and can be tolerated. Studies have shown that probiotics are usually safe for most people, but there are some things that need to be taken into account to make sure they are safe, especially for people who are weak. Formulations and transport methods are very important for making sure that probiotics are alive, stable, and delivered to the right places in the GI tract. Probiotic strains work better in the gut because of improvements in how probiotic preparation technologies protect and control the release of probiotic strains. Personalized methods take into account how each person's microbiome and health are different. By using individual microbiota profiling, custom probiotic approaches can be made to address specific microbial imbalances and promote a healthier microbial environment, which could improve treatment results. Even though individual methods show promise, there are still problems, such as the need to standardize microbiota profiling techniques, figure out how to understand data, and keep track of people over time. For personalized probiotics to reach their full potential and change the way patients are cared for based on the microbiota-host relationship, more study, technological advances, and teamwork are needed. In conclusion, probiotics can be used to change your microbiome in a way that is specific to you and your health goals. By using the power of individualized microbiota profiling, personalized probiotic treatments might be able to help with certain health problems and make the microbial environment better. Putting personalized probiotics into clinical practice and changing the way patients are cared for will require more study and partnerships between different fields.

Breast cancer (BC) is the most common malignancy and the second cause of cancer specific death in women from high-income countries. More than 70% of all breast cancer are hormone receptor-positive BC, and elevated estrogen circulating in blood has been proved to be a strong risk for BC development. This is due to its contribution to enhance proliferation of cancerous cells, angiogenesis and metastasis stimulation and therapy resistance. The estrogen (E) metabolism–gut microbiome axis is functional with underlying individual variations in E levels. It is reasonable that the estrobolome (bacterial genes whose products are capable of metabolizing E) could contribute to the risk of hormone-driven malignancies including BC and may serve as a potential biomarker and target. Gut microbial β -glucuronidase (GUS) enzymes have been suggested to be involved in the estrobolome. Furthermore, bacterial GUS enzymes within the gastrointestinal tract have been postulated to contribute to hormone breast cancer. In this review, we discuss the recent knowledge about the role of GUS enzyme in the pathogenesis of breast cancer. We focus on the role of GUS in (i)-the microbioma and estrogen metabolism, (ii) diet, estrobolome, and the BC development, (iii) other activities of the bacterial β-glucuronidase, and (iv) the new molecular target for BC therapeutic application.

miRNAs are major regulators of eukaryotic gene expression, host immunity, and play an important role in the inflammation-mediated pathways in periodontal disease (PD) pathogenesis. Expanding our previous observation with the global miRNA profiling using partial human mouth microbes and lack of in vivo studies involving oral spirochete Treponema denticola induced miRNAs, this study was designed to delineate the global miRNA expression kinetics during progression of periodontitis in mice infected with T. denticola by using NanoString nCounter® miRNA panels. All the T. denticola-infected male and female mice at 8- and 16 weeks demonstrated bacterial colonization (100%) on the gingival surface, and an increase in alveolar bone resorption (p &lt; 0.0001). A total of 70 miRNAs with at least 1.0-fold differential expression/regulation (DE) miRNAs (26 upregulated and 44 downregulated) were identified. nCounter miRNA expression profiling identified 13 upregulated miRNAs (e.g. miR-133a, miR-378) and 25 downregulated miRNAs (e.g. miR-375, miR-34b-5p) in T. denticola-infected mice mandibles during 8-weeks infection whereas 13 upregulated miRNAs (e.g. miR-486, miR-126-5p) and 19 downregulated miRNAs (miR-2135, miR-142-3p) were observed during 16- weeks of infection. One miRNA (miR-126-5p) showed significant difference between 8-and 16-weeks of infection. Interestingly, miR-126-5p has been presented as a potential biomarker in patients with periodontitis and coronary artery disease. Among the 13 upregulated miRNAs, miR-486, miR-126-3p, miR-126-5p were reported in human gingival plaques samples with periodontitis. KEGG analysis revealed various functional pathways of DE miRNAs such as bacterial invasion of epithelial cells, Ras signaling, Fc gamma R- mediated phagocytosis, osteoclast differentiation, adherens signaling and ubiquitin mediated proteolysis. This is the first study of DE miRNAs in mice mandibles at different time-points of T. denticola infection and the combination of three specific miRNAs miR-486, miR-126-3p, miR-126-5p may serve as an invasive biomarker of T. denticola in PD. These miRNAs may have significant role in PD pathogenesis and establishes a link between miRNA, periodontitis, and systemic diseases.

Since the first description of SARS-CoV-2 in China in 2019, thousands of variants have emerged worldwide. For some of them, the constellation of mutations caused changes in virus biology, pathogenicity, infectivityity and transmissibility resulting in dissemination throughout the world. Gamma variant (P.1) differs from SARS-CoV-2 Wuhan strain (B.1) by 12 amino acids in the Spike (S) protein, and presented mutations related to greater affinity for the receptor angioten-sin-converting enzyme 2 (ACE-2) and/or immune escape. The Gamma variant and subvariants were responsible for the second wave of COVID-19 in the Brazilian city of Manaus, characterized by high mortality and rapid transmission. The ability of variants to induce cytokine production may be closely related to their pathogenicity. Herein we observed that there was no significant difference in the quantity of cytokines among macrophages or neutrophils infected with P.1 and B.1 strains. Also, no significant difference was observed in the absolute number of macrophages and neutrophils infected with these variants. Furthermore, no evidence of SARS-CoV-2 replication was observed in macrophages when infected by the two analyzed variants. Our findings suggest that the difference in the epidemiological outcome observed during the P.1 variant spread when compared to B.1, it is not explained by differences in the quantity of cytokines and absolute number of macrophages or neutrophils. Through bioinformatics analysis of the S protein, we observed that the physicochemical differences between the variants and subvariants of P.1, probably refer to the degree of infectivity, due to the impact caused in the recognition of antibodies and receptor af-finity

A novel group of conjugative plasmids of Pseudomonas is characterized. The prototype plasmid pPPUT-Tik1-1 (153663 bp), isolated from a permafrost strain of P. putida Tik1, carries a defective mercury transposon Tn501 and a streptomycin resistance transposon Tn5393. Ten plasmids and 34 contigs with backbone regions closely related to pPPUT-Tik1-1 have been found in Gene Bank. Two of these plasmids isolated from clinical strains of P. putida and P. fulva are almost identical to the ancient plasmid. A characteristic feature of this group of plasmids is the presence of two genes encoding the initiators of replication (repA1 and repA2). None of these genes has high similarity with plasmid replication genes belonging to known incompatibility groups. It has been demonstrated that while pPPUT-Tik1-1-like plasmids have homologous backbone regions they significantly differ by the molecular structure and the functional burden of their accessory regions. Some of the pPPUT-Tik1-1-related plasmids carry determinants of antibiotic resistance and/or heavy metal salts. Some plasmids are characterized by the ability to degrade xenobiotics. Plasmids related to pPPUT-Tik1-1 are characterized by a narrow host range and are found in various species of Pseudomonas genus. A group of shortened plasmids containing the same replication module, but without conjugation genes, were also found. These plasmids also contain other structural changes that strongly distinguish them from plasmids related to pPPUT-Tik1-1. The data obtained indicate the need for a complex approach to the classification of plasmids.

The global burden of bacterial resistance remains one of the most serious public health concerns. Infections caused by multiresistant (MDR) bacteria in critically ill patients require immediate empirical treatment, which may not only be ineffective due to the resistance of MDR bacteria to multiple classes of antibiotics, but may also contribute to the selection and spread of antimicrobial resistance. Both the WHO and the ECDC consider carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and carbapenem-resistant Acinetobacter baumannii (CRAB) to be the highest priority. The ability to form biofilm and the acquisition of multiple drug resistance, in particular to carbapenems, have made these pathogens particularly difficult to treat. They are a growing cause of healthcare-associated infections and a significant threat to public health, associated with a high mortality rate. Moreover, co-colonization with these pathogens in critically ill patients was found to be a significant predictor for in-hospital mortality. Importantly, they have the potential to spread resistance using mobile genetic elements. Given the current situation, it is clear that finding new ways to combat antimicrobial resistance can no longer be delayed. The aim of this review was to evaluate the literature on how these pathogens contribute to the global burden of AMR. The review also highlights the importance of the rational use of antibiotics and the need to implement antimicrobial stewardship principles to prevent the transmission of drug-resistant organisms in healthcare settings. Finally, the review discusses the advantages and limitations of alternative therapies for the treatment of infections caused by these "titans" of antibiotic resistance.

Despite being a rare disease worldwide, rabies has the highest morbidity and mortality rates, with nearly all symptomatic cases leading to coma and death. Rabies represents an infectious disease caused by the Rabies virus (RABV), which is part of the Lyssavirus group and the Rhabdoviridae family, and it mainly spreads through the bite and scratch of an infected mammal, but particularly of wild animals, such as bats, foxes, wolves and racoons, and of domestic animals, such as dogs and cats, in rabies-prone areas of the world. Airborne transmission has been deemed as extremely rare, and no clinical case as such has been recorded worldwide yet, except in the enclosed environment, such as research laboratories and caves where infected bats are present. Domestic mammals, such as dogs and ferrets, represent other important reservoirs of disease transmission, and the human cases of Asia and Africa amount approximately 95% of all human cases worldwide. Infected animals most commonly start transmitting the virus once the first symptoms have occurred, and if they experience disease aggravation and death within 10 days, a case of rabies is registered, more easily if the incidence occurred in the urban area and then, any person or animal that had been potentially exposed are strongly recommended to receive the inoculation. It is rare for asymptomatic mammals to transmit the illness. Most First-World and several Second-World countries have recently been declared dog rabies-free by the World Health Organization. The disease can only be treated prophylactically, with three doses of a vaccine containing an inactivated form of RABV, or with five doses of the vaccine and two doses of anti-RABV immunoglobulins within 28 days if the patient is believed to have been exposed to the virus beforehand. It has been projected that, once the viral load reaches elements of the central nervous system, prophylactic approaches are no longer effective, even if symptoms have not begun yet, and this highlights the urgent trait of the medical condition, strongly recommending exposed people to receive the prophylactic doses immediately after the potential exposure to the virus. The pathogen first infects the bodily fluids, before reaching the peripheral nervous system, from where it will gradually move toward the spinal cord or the encephalon, at a speed of movement ranging from 1 to 40 cm per day. It was also found, in extremely rare circumstances, to infect the nasopharyngeal cavity and the lungs. The primary cause of a successful, gradual advance of the viral load toward the point of clinical no-return for the patient - the CNS - is a complex mechanism of induced innate immune evasion, with the interferon system being heavily targeted and silenced by RABV proteins. The ‘Milwaukee’ protocol is locally believed to decrease the mortality rate of the clinical illness to approximately 80%, although significantly more research is required in this sense. First-line immune evasion represents the central mechanism developed by viruses during their evolutionary process to gain control over human immunity, so it could be the development and adjustment of a counter-offensive to this evolutionary operating system that could address the core elements of the problem. Human recombinant Type I and Type III Interferons were found to be significant vaccine adjuvants and to considerably delay the clinical onset of the disease. Despite their central role in natural immunity-based prophylaxis, vaccine support and, in often cases, vaccination per se, a local administration of IFNs as such may not be enough to tackle the core problem of the endemic disease, and a specific and systemic treatment of potential host cells with IFN I and III, as well as IFN-stimulating proteins, may constitute a major research requirement in the coming years of disease investigation, as the inoculation efforts with the inactivated virus and immunoglobulin administration continue. The administration of a relatively low dosage of somatic Natural Killer cells, gamma-interferon and perhaps, of somatic helper CD4+ and somatic cytotoxic CD8+ T-lymphocytes treated with alpha-, beta- and lambda-interferon could be merged with the administration of a similar dosage of alpha-, beta- and lambda-interferon during the efforts to develop an effective and less costly prophylactic vaccine against rabies. A combination of a nasal substance containing a low dosage of IFN I and III with a reduced concentration of neutralized RABV copies, and/or with a low dose of anti-RABV IgA antibodies, could also be tested for humans for the purposes of pre- and post-exposure prophylaxis.

The objective of the present study is to isolate phages targeting multidrug resistant (MDR), extended spectrum beta lactamase (ESBL) positive clinical isolate of E. coli ( U1007), sequence and analyze the phage genome and use machine learning tools to predict host cell surface receptor and finally evaluate the efficiency of monophage and phage cocktail in vitro and in vivo in a zebrafish model. Phage specific for E. coli U1007 was isolated from Ganges River (designated as U1G), Cuoom River (designated as CR) and Hospital waste water (designated as M phage). The obtained phages were triple purified and enriched. U1G phages had a greater burst size of 124 PFU/cell and a latent time of 25 min.M phage had a burst size of 150 PFU/cell with a shortlatent time of 20min. Similarly CR phage has a short latent 20 min and a burst size of 115 PFU/cell. Based on capsid architecture, U1G phage resembles Podoviridae, CR phage is structurally similar to Myoviridae and M phage has morphology that resembles Siphoviridae. Genome sequencing and analysis revealed that the size of the U1G phage genome is 73275 bp Whereas that of CR phage and M phage are 45236 bp and 45294 bp, respectively. All three genomes were marked by the absence of genes encoding tRNA sequence, antibiotic resistant or virulent genes. A machine learning (ML) based multi-class classification model using algorithms such as Random Forest, Logistic Regression, and Decision Tree were employed to predict the host receptor targeted by all 3 phages and the best performing algorithm Random Forest predicted LPS O antigen , LamB or OmpC for U1G FhuA, OmpC for CR phage and FhuA, LamB, TonB or OmpF for the M phage as the host receptor targeted by the receptor binding protein (RBP) of the phages. In vitro time kill assay showed that treatment with monophages alone and along with colistin resulted in regrowth whereas phage combinations significantly reduced the regrowth and by 24h the phage cocktail along with colistin produced a significant 3 log declinein cell counts relative to the untreated control. In vivo intramuscular infection study in zebrafish showed that phages were non toxic and a cocktail of dual (U1G +M) phage along with colsitin resulted in a significant 3.5 log decline in cell counts whereas triple phage combination along with colistin resulted in 3 log decline in cell counts probably due to host receptor competition. Our study highlights the potential of phage cocktail therapy in mitigating MDR clinical isolate of E. coli in vitro and in vivo.

Metabolic-associated fatty liver disease (MAFLD) and its potential impact on the severity of COVID-19 have gained significant attention during the pandemic. This review aimed to explore the genetic determinants associated with MAFLD, previously recognized as non-alcoholic fatty liver disease (NAFLD), and their potential influence on COVID-19 outcomes. Various genetic polymorphisms, including PNPLA3 (rs738409), GCKR (rs780094), TM6SF2 (rs58542926), and LYPLAL1 (rs12137855), have been investigated in relation to MAFLD susceptibility and progression. Genome-wide association studies and meta-analyses have revealed associations between these genetic variants and MAFLD risk, as well as their effects on lipid metabolism, glucose regulation, and liver function. Furthermore, emerging evidence suggests a possible connection between these MAFLD-associated polymorphisms and the severity of COVID-19. Studies exploring the association between indicated genetic variants and COVID-19 outcomes have shown conflicting results. Some studies observed a potential protective effect of certain variants against severe COVID-19, while others reported no significant associations. This review highlights the importance of understanding the genetic determinants of MAFLD and its potential implications for COVID-19 outcomes. Further research is needed to elucidate the precise mechanisms linking these genetic variants to disease severity and to develop gene profiling tools for early prediction of COVID-19 outcomes. If confirmed as determinants of disease severity, these genetic polymorphisms could aid in identifying high-risk individuals and improving the management of COVID-19.

Coronavirus Disease-19 (COVID-19) is caused by the infection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). The virus enters host cells through receptor-mediated endocytosis of angiotensin-converting enzyme-2 (ACE2), leading to systemic inflammation, also known as a “cytokine storm,” and neuroinflammation. COVID-19’s upstream regulator, interferon-gamma (IFNG), is downregulated upon the infection of SARS-CoV-2, which leads to the downregulation of ACE2. The neuroinflammation signaling pathway (NISP) can lead to neurodegenerative diseases, such as Parkinson's disease (PD), which is characterized by the formation of Lewy Bodies made of α-Synuclein protein encoded by synuclein alpha (SNCA). This study presents the pathways involved in the downregulation of ACE2 following SARS-CoV-2 infection and its effect on PD progression. Through QIAGEN’s Ingenuity Pathway Analysis, the study identifies the NISP as a top-five canonical pathway/signaling pathway and SNCA as a top-five upstream regulator. Core Analysis was also conducted on the associated molecules between COVID-19 and SNCA to construct a network connectivity map. The Molecule Activity Predictor tool was used to simulate the infection of SARS-CoV-2 by downregulating IFNG, which leads to the predicted activation of SNCA, and subsequently PD, through a dataset of intermediary molecules. Downstream Effect analysis was further used to quantify the downregulation of ACE2 on SNCA activation.

Shiga toxins (Stxs), and more specifically the Stx2a subtype, are the major virulence factors involved in enterohemorrhagic Escherichia coli (EHEC)-associated hemolytic uremic syndrome (eHUS); a life-threatening disease causing acute kidney injury, especially in children. Cleavage of Stxs A subunit, when followed by reduction, boosts the enzymatic activity causing damage to targeted cells. This cleavage was assumed to be mostly mediated by furin during Stx intracellular trafficking. Cleavage of A subunit, without reduction, changes the binding properties of Stxs for blood components during HUS pathogenesis. To investigate whether the cleavage could occur in the intestine, even prior entering target cells, Stx2a structure was characterized after its exposure to specific host factors present in human stool. The structure of Stx2a A subunit was determined by immunoblotting after electrophoretic separation under reducing conditions. Trypsin and chymotrypsin-like elastase 3B (CELA3B), two serine proteases, were identified as potential candidates that may trigger the extracellular cleavage of Stx2a A subunit directly after its secretion by EHEC in the gut. Whether this observation indeed translates to natural infections and plays a role in eHUS pathogenesis has yet to be determined as well as whether host's protease profile could affect disease development by changing the toxin’s biological features.

IQGAP1 is a multi-functional scaffold protein. However, its role in B cell development and function is not known. Here, we demonstrate Iqgap1mice contained significantly increased numbers of B220+ B, B220+IgM pro/pre-B, and B220+IgM+ immature-B cells in the bone marrow. Here, we show IQGAP1 as the essential scaffold that regulates early B cell development and function. Iqgap1mice contained significantly increased numbers of B220+ B, B220+IgM pro/pre-B, and B220+IgM+ immature-B cells in the bone marrow. New-forming and follicular B cell numbers were increased, while the marginal zone B cell numbers were significantly reduced in the spleen of the Iqgap1mice. Lack of IQGAP1 reduced T-dependent and T-independent humoral responses. Mechanistically, the lack of IQGAP1 considerably decreased the phosphorylation of Mek1/2, Erk1/2, and Jnk1/2. B cells from Iqgap1mice failed to suppress IL-7R-mediated activation of Stat5a/b, an essential step for cell-cycle exit and initiate light-chain recombination, leading to a reduction in RS rearrangement frequency. Lack of IQGAP1 resulted in a significant reduction of IRF4 and IRF8 in BM B cells. Our study provides the first evidence that IQGAP1-based signalosome is essential for the development and functions of B cells.

Caries are lesions caused by acidic compounds derived from the metabolism of bacteria such as streptococci. It is not merely the presence of acidogenic bacteria that causes caries but an imbalance in the oral biofilm microhabitat and its behavior. One factor underlying biofilm formation is quorum sensing (QS), that in gram-positives relies on peptidic molecules, whereas in gram-negatives is driven by small diffusible signals. Strategies based on QS inhibition have been proposed as alter-natives to antimicrobial therapies. Here, we investigate the antibiofilm potential of the lactonase enzyme Aii20J, previously reported as effective against biofilms of periodontal disease origin. We generated in vitro polymicrobial biofilms dominated by gram-positive taxa using supragingival samples from caries-free and caries-active children. The effect of Aii20J on the biofilms was evalu-ated regarding its biomass-reducing ability, as assessed with crystal violet assay, and its effects on the bacterial composition of the polymicrobial biofilms, as assessed by 16S community profiling. We describe significant biomass reductions upon Aii20J exposure without significant changes in bac-terial composition at the genus level. Our results support the use of Aii20J to prevent oral biofilm formation while highlighting the influence of the polymicrobial environment on bacterial commu-nities and their response to antibiofilm treatments.

Periodontitis is a widely spread chronic inflammatory disease caused by a changed oral microbiome. Although multiple species and risk factors have been associated with periodontitis, Porphyromonas gingivalis undoubtedly stands in the center as a keystone pathogen. The immune-modulatory function of P. gingivalis has been well characterized, but the mechanism by which peptidyl arginine deiminase (PPAD), a citrullinating enzyme, contributes to the infinite loop of inflammation is not fully understood. To determine the functional role of hypercitrullination in the context of periodontitis, we performed a comparative analysis on neutrophils stimulated by the wild type and the PPAD mutant strain that lacks an active enzyme. Our flow cytometric analysis revealed that PPAD contributes to the prolonged neutrophil survival upon bacteria stimulation, which was accompanied by aberrant IL-6 and TNF-α secretion in the experimental environment. To further elaborate on the complex mechanism by which citrullination sustains the chronic inflammatory state, we assessed the ROS production and phagocytic activity of neutrophils. Flow cytometry and colony formation assay demonstrated that PPAD obstructs the resolution of inflammation by promoting neutrophil survival and the release of pro-inflammatory cytokines while making the bacteria itself more resilient to phagocytosis.

The stability of the gut barrier is very important for keeping the gut healthy and stopping dangerous substances from getting into the bloodstream. Several diseases, including cancer, have been linked to the gut barrier being broken. Live bacteria called probiotics that are good for the host have been shown to have the ability to improve the gut barrier and lower the risk of cancer in the gastrointestinal system. This review looks at how probiotics affect the health of the gut barrier and what that might mean for preventing cancer. Researchers have found that probiotics strengthen the connections between intestine cells, encourage the production of protective mucins, and change the make-up and balance of the gut bacteria. These processes help keep the gut barrier strong and stop harmful chemicals from getting into the bloodstream. Probiotics may help lower the chance of cancer by reducing inflammation throughout the body and protecting the GI tract from harmful substances. But more study is needed to fully understand the benefits of different probiotic strains, the best amounts to take, and how they affect the health of the gut barrier. Understanding how probiotics, the health of the gut barrier, and the risk of cancer all work together can help us come up with new ways to avoid and treat cancer.

Balanced fear supports human rational decision making and useful behavioral responses. In contrast, overwhelming, persistent, and unbalanced fear can paralyze the individual and result in heightened anxiety, lack of cognitive flexibility, fear-based public compliance and serious mental health issues. Psychobiotics research has established that a healthy microbiome is required for balanced fear and mental health protection via control of fear extinction. The recent Covid-19 pandemic featured daily, persistent, fear-of-a single contagion conditioning on a global scale paired with various behavioral mandates (e.g., lockdowns of the healthy, masks, isolation from environmental microbes and each other) that degraded the human microbiome and isolated us from each other and useful environmental microbes. It also ignored the historic role of secondary bacterial pathobionts, in pandemic deaths. This narrative review examines how institutional promotion of fear-of-a single contagion, lack of balanced risk communication, and appalling disregard of our fundamental nature (as majority-microbial human superorganisms) resulted in problems rather than solutions. This review concludes that government-public health-media promotion of pervasive fear and microbiome-degrading behaviors: 1) increased public compliance, 2) reduced cognitive flexibility, and 3) increased risk of mental health conditions. It further argues that microbiome-first public health should be embraced to ensure that human freedom, rather than paralyzing fear, dominates our future.

Lung cancer is the leading cause of cancer death worldwide, with non-small cell lung cancer (NSCLC) making up 80% of cases. Some genetic factors leading to NSCLC development include genetic mutations and PD-L1 expression. PD-L1 proteins are targeted in an NSCLC treatment called targeted gene therapy. However, this treatment is effective in a low percentage of patients. This study aimed to create machine learning models to use features like the number of mutations and the level of PD-L1 proteins in cancer cells, along with others, to predict whether a patient will receive clinical benefit from gene therapy treatment. This was done by downloading and merging datasets from cbioportal.org to create a sample size for the model. Features with high correlations to clinical benefit were identified. Three machine-learning models were created using these features to predict clinical benefits in patients, and each model’s accuracy was evaluated. All three models were accurate between 55-85%, with two of the models averaging an accuracy around 75%. Doctors can use these models to more accurately predict whether gene therapy treatment is likely to work in a patient before prescribing it to them.

Helicobacter pylori is a gastric pathogen that infects nearly half of the global population and is recognized as a group 1 carcinogen by the Word Health Organization. The global rise in antibiotic resistance has increased clinical challenges in treating H. pylori infections. Biofilm growth has been proposed to contribute to H. pylori’s chronic colonization of the host stomach, treatment failures, and the eventual development of gastric diseases. Several components of H. pylori have been identified to promote biofilm growth, and several of these may also facilitate antibiotic tolerance, including the extracellular matrix, outer membrane proteins, the coccoid morphology, modulated metabolism, efflux pumps, and virulence factors. Recent developments in therapeutic approaches targeting H. pylori biofilm have shown that synthetic compounds, such as small molecule drugs and plant-derived compounds, are effective at eradicating H. pylori biofilms. These combined topics highlight the necessity for biofilm-based research in H. pylori, to improve current H. pylori targeted therapeutic approaches and alleviate relative public health burden. In this review we discuss recent discoveries that have decoded the life cycle of H. pylori biofilms and current biofilm targeted treatment strategies.

Bacterial biofilms can cause widespread infection. In addition to causing urinary tract infections and pulmonary infections in patients with cystic fibrosis, biofilms can help microorganisms adhere to the surfaces of various medical devices, causing biofilm-associated infections on the surfaces of biomaterials such as venous ducts, joint prostheses, mechanical heart valves, and catheters. Biofilms provide a protective barrier for bacteria and provide resistance to antimicrobial agents, which increases the morbidity and mortality of patients. This review introduces the formation process and drug resistance mechanism of biofilms in detail, and further summarizes the main characteristics of clinical persistent infection caused by biofilms and the many methods of treating biomaterial-related biofilm. This provides ideas and directions for the development of new biofilm infection strategies related to therapeutic materials.

Helicobacter pylori (H. pylori) is a common bacterial infection linked to gastric malignancies. While H. pylori infection and gastric cancer rates are decreasing, antibiotic resistance varies greatly by community. Little is known about resistance rates among rural Indigenous populations in the United States. From 2018 to 2021, 396 endoscopy patients were recruited from a Northern Arizona clinic, where community H. pylori prevalence is near 60%. Gastric biopsy samples positive for H. pylori (n=67) were sequenced for clarithromycin and metronidazole-associated mutations, 23S ribosomal RNA (23S), and oxygen-insensitive NADPH nitroreductase (rdxA) regions. Medical record data were extracted for endoscopic findings and prior H. pylori history. Data analysis was restricted to individuals with no history of H. pylori infection. Of 49 individuals, representing 64 samples that amplified in the 23S region, a clarithromycin-associated mutation was present in 38.8%, with T2182C the most common mutation, 90%. While prevalence of metronidazole resistance-associated mutations was higher, 93.9%, mutations were more variable, with D95N the most common, followed by L62V. No statistically significant sex differences were observed for either antibiotic. Given the risk of treatment failure with antibiotic resistance, there is a need to consider the resistance profile during treatment selection. The resistance rates in this population of American Indian patients undergoing endoscopy are similar to other high-risk populations. This is concerning given the high H. pylori prevalence and low rates of resistance testing in clinical settings. The mutations reported are associated with antibiotic resistance, but clinical resistance must be confirmed.

Type II grass carp reovirus (GCRV-II) with high pathogenicity and infectivity causes severe hemorrhagic disease, which leads to extensive death in the grass carp and black carp aquaculture. However, the early invasion portal remains unclear. In this study, we explored the invasion portal, time, and pathway of GCRV-II by immersion infection in grass carp. Through the detection of the infected grass carp external body surface tissues, most of them could be detectable to carry GCRV-II within 45 minutes except for the skin covered by scales. Further shortening the duration of infection, we proved that GCRV-II rapidly invades through the nostril (especially), gill, and skin on head at only 5 min post immersion, rather than merely adhesion. Subsequently, visual localization investigations of GCRV-II were conducted on the nostril, olfactory system (olfactory bulb and olfactory tract), and brain by immunofluorescence microscopy and transmission electron microscopy. We found that few viruses were located in the nostril at 5 min post immersion infection, while significantly increased viruses were distributed in all these tissues at 45 min. Furthermore, semi-qRT-PCR and western blotting results of different infection time confirmed that GCRV-II invades grass carp via nostril-olfactory system-brain axis and then unfolds viral replication. These results revealed the infection mechanism of GCRV-II on the invasion portal, time, and pathway in grass carp. This study aims to understand the invasion mode of GCRV-II in grass carp, which provides theoretical support for the prevention and control strategies of hemorrhagic disease.

Psoriatic arthritis (PsA) is a persistent, inflammatory disease that affects individuals with psoriasis, arthritis, and enthesitis. Research has demonstrated that inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-23 (IL-23), and interleukin-17 (IL-17) play a pivotal role in both the onset and progression of PsA. These cytokines are generated by activated immune cells and stimulate the attraction of inflammatory cells to the synovium and joint tissues, resulting in the deterioration of cartilage and bone. The blocking of these cytokines has become a successful treatment strategy for PsA, as biological drugs that inhibit TNF-α, IL-23, and IL-17 have demonstrated notable clinical benefits. The association between PsA and other types of inflammatory cytokines or chemokines, excluding TNF-α, IL-23, and IL-17, has been extensively investigated in numerous studies. These findings may provide a chance for the discovery of novel therapeutic agents targeting other molecules, distinct from the currently approved biologics and targeted synthetic disease-modifying antirheumatic drugs. In this review, we discuss the current understanding of the role of inflammatory cytokines in PsA pathogenesis and clinical implications of targeting these cytokines for PsA treatment.

Abstract: OTUD6A is a deubiquitinase that plays crucial roles in various human diseases. However, the precise regulatory mechanism of OTUD6A remains unclear. In this study, we found that OTUD6A significantly inhibited the production of type I interferon. Consistently, peritoneal macrophages and bone marrow-derived macrophages from Otud6a^-/- mice produced more type I interferon after virus infection compared to cells from WT mice. Otud6a^-/- mice also exhibited increased resistance to lethal HSV-1 and VSV infections, as well as LPS attack due to decreased inflammatory responses. Mechanistically, mass spectrometry results revealed that UBC13 was an OTUD6A-interacting protein, and the interaction significantly enhanced after HSV-1 stimulation. Taken together, our findings suggest that OTUD6A plays a crucial role in the innate immune response and may serve as a potential therapeutic target for infectious disease.

Immune surveillance by natural killer (NK) cells and their recruitment to sites of inflammation renders them susceptible to viral infection, potentially modulating their effector function. Here, we analyzed innate RNA receptor signaling in NK cells downstream of direct Influenza A virus (IAV) infection and its impact on NK cell effector function. Infection of NK cells with IAV resulted in the activation of TBK1, NF-κB and subsequent type-I IFN secretion. CRISPR- generated knockouts in primary human NK cells revealed that this effect depended on the antiviral cytosolic RNA receptor RIG-I. Transfection of NK cells with synthetic 3p-dsRNA, a strong RIG-I agonist that mimics viral RNA, resulted in a similar phenotype and rendered NK cells resistant to subsequent IAV infection. Strikingly, both IAV infection and 3p-dsRNA transfection enhanced degranulation and cytokine production by NK cells when exposed to target cells. Thus, RIG-I activation in NK cells both supports their cell intrinsic viral defense and enhances their cytotoxic effector function against target cells.

Adult T-cell leukemia (ATL) is an aggressive hematologic disease caused by human T-cell leukemia virus type 1 (HTLV-1) infection. Various animal models of HTLV-1 infection/ATL have been established to elucidate the pathogenesis of ATL and develop appropriate treatments. For analyses employing murine models, transgenic and immunodeficient mice are used because of the low infectivity of HTLV-1 in mice. HTLV-1 Tax and HBZ transgenic mice spontaneously develop tumors, and roles for both Tax and HBZ in cell transformation and tumor growth have been established. Severely immunodeficient mice were able to engraft ATL cell lines and have been used in preclinical studies of candidate molecules for the treatment of ATL. HTLV-1-infected humanized mice with an established human immune system are a suitable model to characterize cells in the early stages of HTLV-1 infection. This review outlines the characteristics of mouse models of HTLV-1 infection/ATL and describes progress made in elucidating the pathogenesis of ATL and developing related therapies using these mice.