REVIEW | doi:10.20944/preprints202308.0872.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: macrophage-mediated therapy; macrophage-biomimetics; macrophage-derived particles; selective ligands
Online: 11 August 2023 (13:08:29 CEST)
The concept of targeted drug delivery can be described in terms of the drug’s ability to mimic the other biological objects’ property to localize to target cells or tissues. For example, drug delivery systems based on red blood cells or mimicking some of their useful features, such as long circulation in stealth mode, have been known for decades. On the contrary, therapeutic strategies based on macrophages have gained very limited attention until recently. Here we review two biomimetic strategies associated with macrophages, that can be used to develop new therapeutic modalities: First, the mimicry of certain types of macrophages (i.e., the use of macrophages, including tumor-associated, or macrophage-like particles as a carrier for targeted delivery of therapeutic agents); and Second, the mimicry of ligands, naturally absorbed by macrophages (i.e., the use of therapeutic agents specifically targeted at macrophages). We discuss potential applications of biomimetic systems involving macrophages for the new advancements in treatment of infections, inflammatory diseases, and cancer.
REVIEW | doi:10.20944/preprints202304.0903.v1
Subject: Biology And Life Sciences, Parasitology Keywords: leishmaniasis; immune response; macrophage phenotype
Online: 25 April 2023 (08:36:54 CEST)
Leishmaniasis is a complex infectious parasitic disease caused by protozoa of the genus Leishmania, belonging to a group of neglected tropical diseases. It poses significant global health challenges, particularly in socio-economically disadvantaged regions. Macrophages, as innate immune cells, play a crucial role in initiating the inflammatory response against the pathogens responsible for this disease. Macrophage polarization, the process of differentiating macrophages into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes, is essential for the immune response in leishmaniasis. The M1 phenotype is associated with resistance to Leishmania infection, while the M2 phenotype is predominant in susceptible environments. Notably, various immune cells, including T cells, play a significant role in modulating macrophage polarization by releasing cytokines that influence macrophage maturation and function. Furthermore, other immune cells can also impact macrophage polarization in a T-cell-dependent manner. Therefore, this review comprehensively examines macrophage polarization's role in leishmaniasis and other immune cells' potential involvement in this intricate process.
ARTICLE | doi:10.20944/preprints202004.0278.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: cembranoid; inflammation; macrophage; NFkB; adhesion
Online: 16 April 2020 (13:44:33 CEST)
Inflammation is considered an important target for stroke therapy because it induces secondary brain damage after the initial ischemic insult. Peripheral monocytes migrate to the brain parenchyma after a central insult. They then differentiate to macrophages in a positive feedback fashion contributing to damage instead of ischemic resolution and inflammation control. A cyclic diterpenoid, (1S,2E,4R,6R,7E,11E)-cembra-2,7,11-triene-4,6-diol (4R), decreases neurodegeneration after ischemia with central anti-inflammatory activity. This study aims to determine whether the central anti-inflammatory effect of 4R is effective against peripheral inflammation triggered by brain ischemia. To investigate the anti-inflammatory effect of 4R, we treated macrophages with lipopolysaccharide (LPS) as an inflammatory model, followed by treatment with 4R. Microarray transcriptome analysis of over 30,000 genes identified the differential expression of 393 genes. Genes related to inflammation, cell adhesion, and transcription were validated with qPCR, and reduced expression was determined. Quantification of NF-kB phosphorylation served as a marker for the modulation of inflammation through gene transcription. Our results show that 4R was associated with a reduction in NFKB1 and ITGB5 gene expression, increased phosphorylation of NF-kB, and a decrease in macrophage adhesion in a blood-brain barrier model. These results indicate that 4R can partially modulate the peripheral immune response, making 4R a potential drug against post-ischemic inflammation.
HYPOTHESIS | doi:10.20944/preprints202207.0106.v2
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: mechanobiology; microgravity; macrophage; multiscale; MRTF; radiation
Online: 18 July 2022 (10:59:36 CEST)
Macrophages exhibit impaired phagocytosis, adhesion, migration, and cytokine production in space, hindering their ability to elicit immune responses. Considering that the combined effect of spaceflight microgravity and radiation is multiscale and multifactorial in nature, it is expected that contradictory findings are common in the field. This theory paper reanalyzes research on the macrophage spaceflight response across multiple timescales from seconds to weeks, and spatial scales from the molecular, intracellular, extracellular, to the physiological. Key findings include time-dependence of both pro-inflammatory activation and integrin expression. Here, we introduce the time-dependent, intracellular localization of MRTF-A as a hypothetical confounder of macrophage activation. We discuss the mechanosensitive MRTF-A/SRF pathway dependence on the actin cytoskeleton/nucleoskeleton, microtubules, membrane mechanoreceptors, hypoxia, oxidative stress, and intracellular/extracellular crosstalk. By adopting a multiscale perspective, this paper provides the first mechanistic answer for a three-decade-old question regarding impaired cytokine secretion in microgravity—and strengthens the connection between the recent advances in mechanobiology, microgravity, and the spaceflight immune response. Finally, we hypothesize MRTF involvement and complications in treating spaceflight-induced cardiovascular, skeletal, and immune disease.
REVIEW | doi:10.20944/preprints202112.0416.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: macrophage, bistability, metabolism, systems biology, miRNA
Online: 25 December 2021 (00:02:25 CET)
Macrophages are essential innate immune cells characterized by a high diversity and plasticity. In vitro, their full dynamic range of activation profiles include the classical pro-inflammatory (M1) and the alternative anti-inflammatory (M2) program. Bistability usually arises in biological systems that contain a positive-feedback loop or a mutually inhibitory, double-negative-feedback loop, which are common regulatory motifs reported for macrophage transitions from one activation state to the other one. This switch-like behavior of macrophage is observed at four different levels. First, a decision-making module in signal transduction includes mutual inhibitory interactions between M1 (STAT1 and NF-KB/p50-p65) and M2 (STAT3 and NF-KB/p50-p50) signaling pathways. Second, a switch-like behavior at the gene expression level includes complex network motifs of transcription factors and miRNAs. Third, those changes impact metabolic gene expression leading to several switches in energy production, NADPH and ROS production, TCA cycle functionality, biosynthesis and nitrogen metabolism. Fourth, metabolic changes are monitored by specialized metabolic sensors coupled to AMPK and mTOR activity to provide stability by maintaining the signals to promote either M1 or M2 activation. The targeting of robust molecular switches has the potential to treat a broad range of widespread diseases such as sepsis, cancer or chronic inflammatory diseases.
REVIEW | doi:10.20944/preprints202106.0666.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: macrophage; lymph node; CD169; PD-L1
Online: 28 June 2021 (14:27:12 CEST)
Lymph nodes are secondary lymphoid organs that appear as bean-like nodules usually <1 cm in size, and they are localized throughout the body. Many antigen-presenting cells such as dendritic cells and macrophages reside in lymph nodes, where they mediate host defense responses against pathogens such as viruses and bacteria. In cancers, antigen-presenting cells induce cytotoxic T lymphocytes (CTLs) to react to cancer cell–derived antigens. Macrophages located in the lymph node sinus are of particular interest in relation to anti-cancer immune responses because many studies using both human specimens and animal models have suggested that lymph node macrophages play a key role in activating anti-cancer CTLs. The regulation of lymph node macrophages therefore represents a potentially promising novel approach in anti-cancer therapy.
ARTICLE | doi:10.20944/preprints201804.0028.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: immunomodulatory; Massoia aromatica Becc.; macrophage phagocytosis
Online: 3 April 2018 (03:49:51 CEST)
Massoia (Massoia aromatica Becc., Lauraceae) bark has been widely used as a component of traditional Indonesian medicine. The indigenous people boil or steam the bark for traditional applications. Our preliminary research revealed the potency of Massoia essential oil and its major compound, C-10 Massoialactone as potential immunomodulator in vitro. However, no scientific evidence regarding its in vivo effects is available. Therefore, this study evaluated the potential immunomodulatory effects of Massoia bark infusion on the nonspecific immune response (phagocytosis) of Wistar rats. The aqueous extract of Massoia bark was obtained by boiling pulverized bark in water, and the C-10 massoialactone content of the extract was determined through Thin Layer Chromatography (TLC) densitometry. For the in vitro assay, macrophages were treated with the freeze-dried infusion at the concentrations of 2.5, 5, 10, 20, or 40 μg/mL media. For the in vivo assay, 2-month-old male Wistar rats were divided into 5 groups. The baseline group received distilled water at the dose of 1 mL/100 g BW with the immunostimulant herbal product “X” administered as the positive control at the dose of 0.54 mL/rat. The treatment groups received the infusion at a dose of 100, 300, or 500 mg/100 g BW. Treatments were given orally every day for 14 days. The ability of macrophage cells to phagocyte latex was determined as phagocytic index (PI) and was observed under microscopy with 300 macrophages. The in vitro study revealed that the phagocytic activity of the infusion-treated macrophages significantly increased in comparison with that of the control macrophages in a concentration-dependent manner. Among all treatment concentrations, the concentration of 40 μg/ml provided the highest activity with a PI value of 70.51% ± 1.11%. The results of the in vivo assay confirmed those of the in vitro assay. The results of the present study indicate that Massoia bark can increase the phagocytic activity of rat macrophage cells. Its potential as a naturally derived immunomodulatory agent requires further study.
ARTICLE | doi:10.20944/preprints202308.1788.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: macrophage-based biochip; CD206; bronchoalveolar lavage; diagnostics
Online: 25 August 2023 (07:51:34 CEST)
Progress in macrophage research is crucial for numerous applications in medicine, including cancer and infectious diseases. However, the existing methods to manipulate living macrophages are labor intense and inconvenient. Here we show that macrophage membranes can be reconstituted after storage for months at 4C, with their CD206 receptor selectivity and specificity being similar to that in the living cells. Then, we have developed a mannose ligand, specific to CD206, linked with PEG as IR spectroscopy marker to detect binding with the macrophage receptor. PEG was selected due to its unique adsorption band of C-O-C group at IR spectra, which does not overlap with other biomolecule’s spectroscopic feature. Next, competitive binding assay versus the PEG-bound ligand, has enabled selection of other higher-affinity ligands specific to CD206. Further, those higher-affinity ligands were used to differentiate activated macrophages in patient’s bronchoalveolar (BAL) or nasopharyngeal (NPL) lavage. CD206- control cells (HEK293T) showed only non-specific binding. Therefore, biochips based on reconstituted macrophage membranes as well as PEG-trimannoside as an IR spectroscopic marker, can be used to develop new methods facilitating macrophage research and macrophage-focused drug discovery.
REVIEW | doi:10.20944/preprints202112.0172.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: monocyte subset; heart failure; inflammation; cytokine; macrophage
Online: 10 December 2021 (11:54:31 CET)
Chronic heart failure (CHF) results when heart cannot constantly supply the body tissues with oxygen and required nutrients, and it can be categorized as heart failure (HF) with preserved ejection fraction (HFpEF), and HF with reduced ejection fraction (HFrEF). There are different causes and mechanisms of the HF pathogenesis; however, the inflammation can be regarded as one of the factors promoting both HFrEF and HFpEF. Monocytes, a subgroup of leucocytes, are known as cellular mediators in response to cardiovascular injury and are closely related to inflammatory reactions. These cells are a vital component of the immune system and are the source of macrophages, which participate in cardiac tissue repair after injury. However, the monocytes are not homogenous as thought, and thus can present different functions under different cardiovascular disease conditions. In addition, there is still an open question whether the functions of monocytes and macrophages should be regarded as a cause or a consequence in CHF development. Therefore, our aim was to summarize the current studies on the function of various monocyte subsets in CHF with a focus on the role of a certain monocyte subset in HFpEF and HFrEF patients, and the relation to inflammatory markers.
REVIEW | doi:10.20944/preprints202012.0272.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: connexin-43; Cx43; gja1; connexins; macrophage; monocyte
Online: 11 December 2020 (09:29:57 CET)
Knowledge on the function of Connexin-43 on macrophages is gradually increasing and recent studies show how macrophages utilise Connexin-43. Migration, antigen-presentation and some forms of intercellular communication in macrophages are Connexin-43-dependant. Delicate processes, such as electrochemical support in conduction of the heartbeat in the AV-node, immunomodulatory regulation in the lungs and macrophage-differentiation are performed using Connexin-43 in macrophages. The relevance on pathophysiology becomes evident in inflammatory bowel disease, tumour networks and HIV in which aberrant function of Connexin-43 has been observed. Although many physiological, as well as pathophysiological functions were found to be Connexin-43-dependant, some still remain debated: the involvement of Connexin-43 in phagocytosis and polarisation, as well as its involvement in the mortality in murine sepsis are still unclear. These functions as well as further involvement in increasingly complex functions of the macrophage pose possible fields of research.
ARTICLE | doi:10.20944/preprints202309.0464.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: carotid atherosclerosis; macrophage; intraplaque neovascularization; atherothrombosis; intraplaque hemorrhage
Online: 7 September 2023 (10:47:14 CEST)
Background: Atherosclerosis is a progressive disease that results from a combination of endothelial dysfunction and inflammatory arterial wall disorder. Stenosis of the carotid artery caused by atherosclerotic plaques is responsible for approximately 10-20% of strokes and transient ischemic attacks, and the low-grade intraplaque inflammation interferes with lesion stability and progression. Methods: In this cohort study, initially, 119 patients were enrolled who underwent carotid endarterectomy. Of these, 67 cases with active perilesional inflammatory infiltrate were chosen for further immunohistochemical examination. The CD68+ infiltrate, iNOS2+, Arg1, and CD31 expressions were quantified around the lipid core by digital morphometry. These results were correlated with the presence of morphological changes leading to plaque instability: ulceration, thrombosis, intraplaque hemorrhage, the presence of the lipid core, calcification, and neovascularization. Results: Patients with a stronger macrophage CD68+ infiltrate were associated with intraplaque hemorrhage (p=0.003). In 12 cases with dominant iNOS2 positivity, the occurrence of atherothrombosis was significantly more frequent (p=0.046). Plaque neovascularization, characterized by CD31+, was correlated with atherothrombosis (p=0.02). Conclusion: The intensity of macrophage infiltration correlates with intraplaque hemorrhage, and the presence of pro-inflammatory iNOS2+ macrophages is associated with atherothrombosis in endarterectomized carotid plaques. Neovascularization also has potential thrombotic capacity.
ARTICLE | doi:10.20944/preprints202308.1977.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Macrophage; Kupffer cell; interferon gamma; Ebola virus; filovirus
Online: 29 August 2023 (14:17:01 CEST)
Ebola virus disease (EVD) represents a global health threat. The etiological agents of EVD are 6 species of Orthoebolaviruses, with Orthoebolavirus zairense (EBOV) having the greatest public health and medical significance. EVD disease pathogenesis occurs as a result of broad cellular tropism of the virus, robust viral replication and a potent and dysregulated production of cytokines. In vivo, tissue macrophages are some of the earliest cells infected and contribute significantly to virus load and cytokine production. While EBOV is known to infect macrophages and to generate high titer virus in the liver, EBOV infection of liver macrophages, Kupffer cells, has not previously been examined in tissue culture or experimentally manipulated in vivo. Here, we employed primary murine Kupffer cells (KC) and an immortalized murine Kupffer cell line (ImKC) to assess EBOV-eGFP replication in liver macrophages. KCs and ImKCs were highly permissive for EBOV infection and IFN-γ polarization of these cells suppressed their permissiveness to infection. The kinetics of IFN-γ-elicited antiviral responses were examined using a biologically-contained model of EBOV infection termed EBOV ΔVP30. The antiviral activity of IFN-γ was transient, but a modest ~3-fold reduction of infection persisted for as long as 6 days post treatment. To assess the interferon stimulated gene products (ISGs) responsible for protection, the efficacy of secreted ISGs induced by IFN-γ were evaluated. Secreted ISGs blocked recombinant VSV expressing EBOV GP (rVSV/EBOV GP) infection, but failed to block EBOV ΔVP30. Our studies define new cellular tools for the study of EBOV infection that can potentially aid the development of new antiviral therapies. Furthermore, our data underscore the importance of macrophages in EVD pathogenesis and those IFN-γ-elicited ISGs that help to control EBOV infection.
ARTICLE | doi:10.20944/preprints202307.1718.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: VDUP1; inflammation; macrophage infiltration; NF-B; ulcerative colitis
Online: 26 July 2023 (05:28:59 CEST)
The loss of vitamin D3 upregulated protein 1 (VDUP1) has been implicated in the pathogenesis of various inflammation-related diseases. Notably, reduced expression of VDUP1 has been observed in clinical specimens of ulcerative colitis (UC). However, the role of VDUP1 deficiency in colitis remains unclear. In this study, we investigated the role of VDUP1 in dextran sulfate sodium (DSS)-induced experimental colitis in mice. VDUP1-deficient mice were more susceptible to DSS-induced colitis than their wild-type (WT) littermates after 2% DSS administration. VDUP1-deficient mice exhibited an increased disease activity index (DAI) and histological scores, as well as significant colonic goblet cell loss and an increase in apoptotic cells. These changes were accompanied by a significant decrease in MUC2 mRNA expression and a marked increase in proinflammatory cytokines and chemokines within damaged tissues. Furthermore, phosphorylated NF-B p65 expression was significantly upregulated in damaged tissues in the context of VDUP1 deficiency. VDUP1 deficiency also led to significant infiltration of macrophages into the site of ulceration. An in vitro chemotaxis assay confirmed that VDUP1 deficiency enhanced bone marrow-derived macrophage (BMDM) chemotaxis induced by CCL2. Overall, the loss of VDUP1 plays a critical role in the pathogenesis of UC, and blocking VDUP1 dissociation may represent a promising therapeutic strategy for the treatment of UC.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: lung adenocarcinoma; macrophage; PD-L1; GM-CSF; STAT3
Online: 11 June 2021 (13:08:03 CEST)
Background; Programmed death-1 (PD-1) and PD-1 ligand 1 (PD-L1) are target molecules for immunotherapy in non-small cell lung cancer. PD-L1 is expressed not only in cancer cells, but also on macrophages, and has been suggested to contribute to macrophage-mediated immune suppression. Methods; Clinical significance of PD-L1 expression on macrophages in human lung adenocarcinoma was examined. The mechanisms of PD-L1 overexpression on macrophages were investigated by means of cell culture studies. Results; High PD-L1 expression on macrophages was correlated with the presence of EGFR mutation, a lower cancer grade, and a shorter cancer-specific overall survival. In an in vitro study using lung cancer cell lines and human monocyte-derived macrophages, the conditioned medium from cancer cells was found to up-regulate PD-L1 expression on macrophages via STAT3 activation, and a cytokine array revealed that granulocyte-macrophage colony-stimulating factor (GM-CSF) was a candidate factor that induced PD-L1 expression. Culture studies using recombinant GM-CSF, neutralizing antibody, and inhibitors indicated that PD-L1 overexpression was induced via STAT3 activation by GM-CSF derived from cancer cells. Conclusions; PD-L1 overexpression on macrophages via the GM-CSF/STAT3 pathway was suggested to promote cancer progression in lung adenocarcinoma. Cancer cell-derived GM-CSF might be a promising target for anti-cancer therapy.
ARTICLE | doi:10.20944/preprints202307.2027.v1
Subject: Medicine And Pharmacology, Gastroenterology And Hepatology Keywords: nuclear receptor; small heterodimer partner (SHP); knockout; macrophage; differentiation
Online: 31 July 2023 (10:24:05 CEST)
Hepatic macrophages act as the liver’s first line of defense against injury. Their differentiation into pro-inflammatory or anti-inflammatory subpopulations is a critical event that maintains a delicate balance between liver injury and repair. In our investigation, we explored the influence of the small heterodimer partner (SHP), a nuclear receptor primarily associated with metabolism, on macrophage differentiation during the innate immune response. During macrophage differentiation, we observed significant alterations in Shp mRNA expression. Deletion of SHP promoted M1 differentiation while interfering with M2 polarization. Conversely, overexpression of SHP resulted in increased expression of peroxisome proliferator activated receptor gamma (Pparg), a master regulator of anti-inflammatory macrophage differentiation, thereby inhibiting M1 differentiation. Upon lipopolysaccharide (LPS) injection, there was a notable increase in the pro-inflammatory M1-like macrophages, accompanied by exacerbated infiltration of monocyte-derived macrophages (MDMs) into the livers of Shp myeloid cell specific knockout (Shp-MKO). Concurrently, we observed significant induction of tumor necrosis factor alpha (Tnfa) and chemokine (C-C motif) ligand 2 (Ccl2) expression in LPS-treated Shp-MKO livers. Additionally, the mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-kB) pathways were activated in LPS-treated Shp-MKO livers. Consistently, both pathways were hindered in SHP overexpression macrophages. Finally, we demonstrated that SHP interacts with p65, thereby influencing macrophage immune repones. In summary, our study uncovered a previously unrecognized role of SHP in promoting anti-inflammatory macrophage differentiation during the innate immune response. This was achieved by SHP acting as a regulator for the Pparg, MAPK and NF-kB pathways.
HYPOTHESIS | doi:10.20944/preprints202211.0407.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: Autism; autism spectrum disorder; autophagy; macrophage polarization; neurogenesis; taurine
Online: 22 November 2022 (05:46:47 CET)
Contemporary research has found that people with autism spectrum disorder (ASD) exhibit aberrant immunological function, with a shift toward increased cytokine production and unusual cell function. Microglia and astroglia were found to be significantly activated in immuno-cytochemical studies, and cytokine analysis revealed that the macrophage chemoattractant protein-1 (MCP-1), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and transforming growth factor β-1 (TGFB-1), all generated in the neuroglia, constituted the most predominant cytokines in the brain. Taurine (2-aminoethanesulfonic acid) is a promising therapeutic molecule able to increase the activity of antioxidant enzymes and ATPase, which may be protective against aluminum-induced neurotoxicity. It can also stimulate neurogenesis, synaptogenesis, and reprogramming of proinflammatory M1 macrophage polarization by decreasing mitophagy (mitochondrial autophagy) and raising the expression of the markers of the anti-inflammatory and pro-healing M2 macrophages, such as macrophage mannose receptor (MMR, CD206) and IL-10, while lowering the expression of the M1 inflammatory factor genes. Taurine also induces autophagy, which is a mechanism that is impaired in microglia cells and is critically associated with the pathophysiology of the ASD. We hypothesize here that taurine could reprogram the metabolism of M1 macrophages that are overstimulated in the nervous system of people suffering from ASD, thereby decreasing the neuroinflammatory process, neuronal death, and improving cognitive functions. Therefore, we think that taurine can serve as an important lead for the development of novel drugs for the ASD treatment.
REVIEW | doi:10.20944/preprints202111.0439.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: HIV; Macrophages; MDM; restriction factors; transcription factors; macrophage polarization
Online: 23 November 2021 (16:19:11 CET)
In addition to CD4+ T lymphocytes, myeloid cells, and, particularly, differentiated macrophages, are targets of the human immunodeficiency virus type-1 (HIV-1) infection via interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication although with substantial differences. In contrast to activated CD4+ T lymphocytes, HIV-1 replication in macrophages occurs in nondividing cells and it is characterized by virtual absence of cytopathicity both in vitro and in vivo. These general features should be considered in evaluating the role of cell-associated restriction factors aiming at preventing of curtailing virus replication in macrophages and T cells particularly in the context of designing strategies to tackle the viral reservoir in infected individuals receiving combination antiretroviral therapy. In this regard, we will here also discuss a model of reversible HIV-1 latency in primary human macrophages and the role of host factor determining restriction or reactivation of virus replication in myeloid cells.
ARTICLE | doi:10.20944/preprints202108.0418.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: CAST; Lgr5; WNT; Gastric cancer; Machine assisted searching; macrophage
Online: 20 August 2021 (14:00:27 CEST)
Background: Gastric cancer (GC) is one of the leading malignancy diseases worldwide, especially in Asian. CAST is a potential oncogene in GC carcinogenesis process. The character of macrophage infiltration in GC microenvironment was also unaddressed. Methods: We first applied machine searching in gene candidate evaluation of GC. CAST expression was analyzed via the Human Protein Atlas (HPA) and Gene Expression Profiling Interactive Analysis 2 (GEPIA2) database. Protein-protein interaction (PPI) network was downloaded from STRING. We investigated the impact of CAST on clinical prognosis using Kaplan-Meier plotter. The correlations between CAST and Lgr5 and macrophage infiltration in GC was surveyed via TIMER 2.0. Finally, GeneMANIA was also used to evaluate the possible functional linkage between genes. Results: After machine-assisted searching, CAST expression was found signicant difference in the overall survival of GC patients. STRING revealed CAST related proteomics and transcriptomics associations, mainly about CAPN family. Moreover, CAST significantly impacts the prognosis of GC from other datasets validation. Notably, high CAST expression was correlated with worse overall survival in GC patients (hazard ratio = 1.59; logrank P = 9.4 x 10-8). CAST and Lgr5 expressions were both positively correlated with WNT 2 and WNT 2B. Among GC patients in several datasets, CAST and macrophage infiltration evaluated together showed no obvious trend toward poor clinical overall survival. Conclusion: CAST plays an important role in GC clinical prognosis and is associated with WNT 2/WNT 2B/Lgr5. Our study denmostrated that CAST in GC overall survival is regulated by macrophage infiltration.
ARTICLE | doi:10.20944/preprints202305.1366.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: regulatory macrophage; arginylglycylaspartic acid; vitamin D3; anti-inflammation; xenotrans-plantation
Online: 19 May 2023 (03:26:46 CEST)
Regulatory macrophages (Mregs) are unique in that they have anti-inflammatory and immunosuppressive properties. Thus, treating inflammatory diseases using Mregs is an area of active research. Human Mregs are usually generated by culturing peripheral blood monocytes stimulated by macrophage colony-stimulating factor with interferon (IFN)-. Here, we generated Mregs with an elongated cell morphology from THP-1 cells stimulated with phorbol 12-myristate 13-acetate and cultured with arginylglycylaspartic acid and vitamin D3. These Mregs regulated macrophage function, and respectively downregulated and upregulated the expression of pro-inflammatory and immunosuppressive mediators. They also expressed Mregs-specific marker, such as dehydrogenase/reductase 9, even when exposed to inflammatory stimulants such as IFN-, lipopolysaccharide, purified xenogeneic antigen, and xenogeneic cells. The Mregs also exerted anti- inflammatory and anticoagulatory actions in response to xenogeneic cells and immunosuppressive effects on mitogen-induced Jurkat T-cell proliferation. Our method of generating functional Mregs in vitro without cytokines is simple and cost-effective.
REVIEW | doi:10.20944/preprints202209.0354.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Wound healing; metastasis; oxidative stress; macrophage; HIF; NF-kB; Nrf2
Online: 23 September 2022 (03:28:28 CEST)
Many signaling pathways, molecular and cellular actors which are critical for wound healing have been implicated in cancer metastasis. These two conditions are a complex succession of cellular biological events and accurate regulation of these events is essential. Apart from inflammation, macrophages-released ROS arise as major regulators of these processes. But, whatever the pathology concerned, oxidative stress is a complicated phenomenon to control and requires a finely tuned balance over the different stages and responding cells. This review provides an overview of the pivotal role of oxidative stress in both wound healing and metastasis, encompassing the contribution of macrophages. Indeed, macrophages are major ROS producers but also appear as their targets since ROS interfere with their differentiation and function. Elucidating ROS functions in wound healing and metastatic spread may allow the development of innovative therapeutic strategies involving redox modulators.
ARTICLE | doi:10.20944/preprints202206.0236.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: uveal melanoma; BAP1; PROS1; MERTK; macrophage; tumor immune microenvironment; metastasis
Online: 16 June 2022 (10:42:50 CEST)
Uveal melanoma (UM) is the most common primary cancer of the eye and is associated with a high rate of metastatic death. UM can be stratified into two main classes based on metastatic risk, with class 1 UM having a low metastatic risk and class 2 UM having a high metastatic risk. Class 2 UM have a distinctive genomic, transcriptomic, histopathologic, and clinical phenotype characterized by biallelic inactivation of the BAP1 tumor suppressor gene, an immune suppressive microenvironment enriched for M2-polarized macrophages, and poor response to checkpoint inhibitor immunotherapy. To identify potential mechanistic links between BAP1 loss and immune suppression in class 2 UM, we performed an integrated analysis of UM samples, as well as genetically engineered UM cell lines and uveal melanocytes (UMC). Using RNA sequencing (RNA-seq), we found that the most highly up-regulated gene associated with BAP1 loss across these datasets was PROS1, which encodes a ligand that triggers phosphorylation and activation of the immunosuppressive macrophage receptor MERTK. The inverse association between BAP1 and PROS1 in class 2 UM was confirmed by single-cell RNA-seq, which also revealed that MERTK was up-regulated in CD163+ macrophages in class 2 UM. Using ChIP-seq, BAP1 knockdown in UM cells resulted in an accumulation of H3K27ac at the PROS1 locus, suggesting epigenetic regulation of PROS1 by BAP1. Phosphorylation of MERTK in RAW 264.7 monocyte-macrophage cells was increased upon co-culture with BAP1-/- UMCs, and this phosphorylation was blocked by depletion of PROS1 in the UMCs. These findings were corroborated by multi-color immunohistochemistry, where class 2/BAP1-mutant UMs demonstrated increased PROS1 expression in tumor cells and increased MERTK phosphorylation in CD163+ macrophages compared to class 1/BAP1-wildtype UMs. Taken together, these findings provide a mechanistic link between BAP1 loss and suppression of the tumor immune microenvironment in class 2 UMs, and they implicate the PROS1-MERTK pathway as a potential target for immunotherapy in UM.
REVIEW | doi:10.20944/preprints202203.0021.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Extracellular Traps; Inflammation; Neutrophils; Basophils; Macrophage/Monocytes; Therapeutic Targets; autoimmunity
Online: 1 March 2022 (12:39:13 CET)
The first description of a new form of neutrophil cell death distinct from that of apoptosis or necrosis was discovered in 2004 and coined neutrophil extracellular traps “(NETs)” or “NETosis”. Different stimuli for NET formation, and pathways that drive neutrophils to commit to NETosis have been elucidated in the years that followed. Critical enzymes required for NET formation have been discovered, and targeted therapeutically. NET formation is no longer restricted to neutrophils but has been discovered in other innate cells: Macrophages/Monocytes, Mast Cells, Eosinophils, Basophils, Dendritic cells, and extracellular DNA is extruded from both B and T cells. It has become clear that although this mechanism is thought to enhance host defence by ensnaring bacteria within large webs of DNA to increase bactericidal killing capacity, it is also injurious to innocent bystander tissue. Proteases and enzymes released from extracellular traps (ETs), injure epithelial and endothelial cells perpetuating inflammation. In the context of autoimmunity ETs release over 70 well known autoantigens. ETs are associated with pathology in multiple diseases: lung diseases, vasculitis, autoimmune kidney diseases, atherosclerosis, rheumatoid arthritis and psoriasis. Defining these pathways that drive ET release will provide insight into mechanisms of pathological insult, and provide potential therapeutic targets.
REVIEW | doi:10.20944/preprints202006.0339.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: ACE2; COVID-19; SARS-CoV-2; alveolar macrophage; thrombus; thrombosis
Online: 28 June 2020 (10:34:52 CEST)
The main manifestation of new coronavirus disease 2019 (COVID-19) is respiratory disease. The new coronavirus (SARS-CoV-2) attacks the lungs and may result in severe acute respiratory syndrome. In such cases, the infected person has difficulty breathing, which impairs oxygen uptake in the body. If pneumonia or another respiratory illness develops, and the host immune system is unable to combat SARS-CoV-2, the infected person may eventually die. Meanwhile, reports on unexpected symptoms in organs other than the nasal cavity, throat, and lungs are emerging. To elucidate the causes of such symptoms, we analyzed the expression status of angiotensin-converting enzyme 2 (ACE2), the host receptor used by SARS-CoV-2, in various tissues. This study confirmed that alveolar macrophages appear to be involved in pneumonitis and thrombus formation. In this report, we introduce some new symptoms.
REVIEW | doi:10.20944/preprints202004.0071.v1
Subject: Medicine And Pharmacology, Epidemiology And Infectious Diseases Keywords: COVID-19; SARS CoV; macrophage activation syndrome; cytokine storm; immunology
Online: 6 April 2020 (16:22:42 CEST)
Introduction: The COVID-19 pandemic is a global crisis, the number of cases and deaths are on a steep incline. This article reviews the possible immunological mechanisms which underlie the disease pathogenesis by looking at the behaviour of previous coronaviruses not only in humans but also other mammals which possibly act as reservoir hosts. Observations: A key aspect of this coronavirus as well as the previous SARS CoV seems to be the importance of host immune response in the pathology and clinical severity of illness caused by them. A hyperactive innate immune state in combination with an exhausted adaptive immune response are possible determinants of severe illness. Conclusion: There is a possibility that the current SARS CoV 2 has immune evasive tactics similar to SARS CoV in its repertoire, since they share a 76% homology. These might have been learnt behaviour from long periods of persistence in their reservoir hosts and they may be the reason behind the dysregulated immune response evoked in humans. That in turn is highly likely to be one of the factors which govern disease severity. With this in mind we want to bring the medical community’s attention to a ‘hit early, hit hard’ intervention as a possible strategy to modify the course of the disease and bring down the numbers of severe sufferers.
REVIEW | doi:10.20944/preprints202310.0145.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: chronic liver disease; specialized pro-resolving mediators; inflammation; macrophage polarization; inmunometabolism
Online: 3 October 2023 (11:11:29 CEST)
The complex interplay between dietary factors, inflammation, and macrophage polarization is pivotal in the pathogenesis and progression of chronic liver diseases (CLDs). Omega-3 fatty acids (FAs) have been attracted attention due to their potential to modulate inflammation and exert protective effects in various pathological conditions. This review explores the emerging role of omega-3 FAs and their specialized pro-resolving mediators (SPMs) in the context of macrophage polarization, with a focus on chronic liver diseases. Omega-3, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have promising effects in mitigating inflammation and enhancing the resolution of inflammatory responses. They influence the M1/M2 macrophage phenotype balance, promoting a shift towards the M2 anti-inflammatory phenotype. SPMs, such as resolvins (Rvs), protectins (PDs), and maresins (MaRs), have emerged as potent regulators of inflammation and macrophage polarization. They show anti-inflammatory and pro-resolving properties. These mediators modulate the expression of cytokines, facilitate the phagocytosis of apoptotic cells, and promote tissue repair. MaR1, in particular, has demonstrated significant hepatoprotective effects by promoting M2 macrophage polarization, reducing oxidative stress, and inhibiting key inflammatory pathways such as NF-κB. In the context of CLD, such as nonalcoholic fatty liver disease (NAFLD) and cirrhosis, omega-3 and their SPMs have shown promise in attenuating liver injury, promoting tissue regeneration, and modulating macrophage phenotypes. However, the mechanisms underlying their effects and their interactions with other cell types within the liver microenvironment require further investigation. Understanding the intricate relationship among SPM and macrophage polarization holds unlimited potential for the development of novel therapeutic strategies for chronic liver diseases.
REVIEW | doi:10.20944/preprints202308.1536.v2
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Multiregional sequencing; multi-sample sequencing; targeted cancer therapy; OVERCOME; macrophage magnetotaxis
Online: 7 September 2023 (02:54:00 CEST)
Some tumors occur in anatomical regions that are hard to biopsy with a needle. Such regions include the brain, spinal cord, liver, and lungs. For the latter two, magnetic nanoparticle-loaded macrophages could be intravenously infused and driven via an MRI machine into the tumor or tumors. Once there, they can be induced to phagocytose whole tumor cells. They would keep their target in a non-digested form by inhibiting phagosome maturation - and be directed via magnetotaxis or chemotaxis to an extraction point in the body where they can be more easily collected via needle.
REVIEW | doi:10.20944/preprints202305.1549.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: multiple sclerosis; oligodendrocyte; myelination; inflammation; microglia; macrophage; bi-omarkers; imaging diagnostics
Online: 23 May 2023 (03:39:19 CEST)
Multiple sclerosis (MS) is a heterogeneous disease of the central nervous system that is governed by neural tissue loss and dystrophy during its progressive phase, with complex reactive pathological cellular changes. The immune-mediated mechanisms that promulgate the demyelinating lesions during the relapses of acute episodes are not characteristic of chronic lesions during progressive MS. This has limited our capacity to target the disease effectively as it evolves within the central nervous system white and gray matter, thereby leaving neurologists without effective options to manage individuals as they transition to a secondary progressive phase. The current review highlights the molecular and cellular sequelae that have been identified to cooperate and/or contribute to neurodegeneration that identifies individuals with progressive forms of MS. We emphasize the need for appropriate monitoring via known and novel molecular and imaging biomarkers that can accurately detect and predict progression for the purposes of newly designed clinical trials that may demonstrate efficacy of neuroprotection and potentially neurorepair. To achieve neurorepair, we focus on the modifications required in the reactive cellular and extracellular milieu, in order to enable endogenous cell growth as well as transplanted cells that can integrate and/or renew the degenerative MS plaque.
ARTICLE | doi:10.20944/preprints201911.0177.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: macrophage migration inhibitory factor; HNSCC cell lines; proliferation; cell cycle; apoptosis
Online: 15 November 2019 (08:48:50 CET)
Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine that contributes to the progression of several cancers. MIF overexpression has been reported in head and neck squamous cell carcinoma (HNSCC) patients. However, the exact role of MIF in HNSCC is not fully understood. Our aim was to evaluate the amount of secreted MIF and the role of MIF in the proliferation, cell cycle, and apoptosis in HNSCC cell lines. The MIF levels in conditioned media from human primary (HN18 and HN30) and metastatic (HN17 and HN31) HNSCC cell lines were evaluated using ELISA. The HNSCC cell lines were treated with recombinant MIF and its effect on proliferation, cell cycle, and apoptotic status was determined by MTT and flow cytometry, respectively. The HNSCC-secreted MIF concentration ranged from 49.33‒860 pg/ml. Exogenous MIF (25 ng/ml) significantly increased HN18, HN30, and HN31 cell proliferation. Moreover, MIF induced cell cycle progression and inhibited apoptosis in these cells. However, MIF did not affect growth or apoptosis in HN17 cell. In conclusion, the HNSCC cell lines were evaluated secrete MIF. Exogenous MIF promotes various effects on proliferation, cell cycle, and apoptosis in HNSCC cells.
HYPOTHESIS | doi:10.20944/preprints202305.0420.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: macrophage-derived chemokine; MDC/CCL22, chemokines; novel coronavirus infection; COVID-19; post-COVID
Online: 6 May 2023 (10:40:04 CEST)
Macrophage-derived chemokine belongs to the CC subfamily. It is produced by dendritic cells (DCs) and macrophages with or without external stimulation. We have previously shown a statistically significant depletion of MDC/CCL22 concentrations in a number of studies concerning COVID-19. These shifts in concentrations demonstrated stability unrelated to the SARS-CoV-2 genetic variant and remained noticeable even in convalescent patients. In this work, we analyze MDC/CCL22 dynamics in various diseases, including those that manifest with inflammation in lung tissue. In addition, we provide our hypothesis on such a decrease in MDC/CCL22 concentrations in COVID-19. If its secretion by producer cells is unperturbed, then it is possible for viral products to bind to this chemokine and to block its functional activity. There is, however, another possible explanation directly linked to depletion in DC subpopulations and the inhibition of their function. We also discuss MDC/CCL22's role in the immunology of novel coronavirus infection, based on both our own data and other studies.
REVIEW | doi:10.20944/preprints202210.0342.v1
Subject: Biology And Life Sciences, Virology Keywords: long COVID; PASC; long haulers; NETosis; T cell; NK cell; DC; neutrophil; macrophage
Online: 24 October 2022 (02:12:06 CEST)
A significant number of persons with coronavirus disease 2019 (COVID-19) experience persistent, recurrent, or new symptoms several months after the acute stage of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection. This phenomenon, termed Post-Acute Sequelae of SARS-CoV-2 (PASC) or Long COVID, is associated with high viral titers during acute infection, a persistently hyperactivated immune system, tissue injury by NETosis-induced micro-thrombofibrosis (NETinjury), microbial translocation, complement deposition, fibrotic macrophages, the presence of auto-antibodies, and lymphopenic immune environments. Here, we review the current literature on the immunological imbalances that occur during PASC. Specifically, we focus on data supporting common immunopathogenesis and tissue injury mechanisms shared across this highly heterogenous disorder including NETosis, coagulopathy, and fibrosis. Mechanisms include changes in leukocyte subsets/functions, fibroblast activation, cytokine imbalances, lower cortisol, autoantibodies, co-pathogen reactivation, and residual immune activation driven by persistent viral antigens and/or microbial translocation. Taken together, we develop the premise that SARS-CoV-2 infection results in PASC as a consequence of acute and/or persistent single or multiple organ injury mediated by PASC determinants to include degree of host response (inflammation, NETinjury), residual viral antigen (persistent antigen) and exogenous factors (microbial translocation). Determinants of PASC may be amplified by co-morbidities, age, and sex. Keywords: long COVID, PASC, long haulers, NETosis, T cell, NK cell, DC, neutrophil,
ARTICLE | doi:10.20944/preprints202107.0687.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Vesicular Stomatitis Virus; macrophage; microarray analysis; differential gene expression; molecular pathogenesis; immune evasion
Online: 30 July 2021 (09:27:29 CEST)
Molecular mechanisms associated with the pathogenesis of Vesicular stomatitis virus (VSV) in livestock remain poorly understood. Several studies have highlighted the relevant role of macrophages in controlling the systemic dissemination of VSV during infection in different animal models, including mice, cattle and pigs. To gain more insight on the molecular mechanisms used by VSV to impair the immune response in macrophages, we used microarrays to determine the transcriptomic changes produced by VSV infection in primary cultures of porcine macrophages. The results indicated that VSV infection induced the massive expression of multiple anorexic, pyrogenic, proinflammatory and immunosuppressive genes. Overall, the interferon (IFN) response appeared suppressed, leading to the absence of stimulation of interferon-stimulated genes (ISG). Interestingly, VSV infection promoted the expression of several genes known to downregulate the expression of IFNb. This represents an alternate mechanism for VSV control of the IFN response, beyond the recognized mechanisms mediated by the matrix protein. Although there was no significant differential gene expression in macrophages infected with a highly virulent epidemic strain compared to a less virulent endemic strain, the endemic strain consistently induced higher expression of all upregulated cytokines and chemokines. Collectively, this study provides novel insights into VSV molecular pathogenesis and immune evasion that warrants further investigation
ARTICLE | doi:10.20944/preprints201810.0686.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Rhus verniciflua Stokes; in vivo; inflammation; macrophage; monocyte differentiation; MHC II; IL-12
Online: 29 October 2018 (13:26:02 CET)
The bark of Rhus verniciflua Stokes (RVS) is used as a food additive and herbal medicine for various inflammatory disorders and cancer in Eastern Asia. RVS exerted anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, but whether this effect occurs in macrophages after oral administration has not been determined. We used a thioglycollate-induced peritonitis model to obtain macrophages from mice given RVS. We examined the systemic inflammatory response to intraperitoneal LPS. RVS-treated mice had an increased population of peritoneal exudate cells expressing CD11b and SRA. Increased uptake of Alexa Fluor 488-labeled acetylated lipoprotein was observed in monocyte-derived macrophages from RVS-treated mice. When these cells from the RVS group were stimulated with LPS, the levels of tumor necrosis factor (TNF)- and interleukin (IL)-6 in the supernatant decreased, but the level of IL-12 increased. The surface expression of CD86 was reduced, but surface expression of class II MHC molecules was increased. RVS suppressed the serum levels of LPS-induced TNF- and IL-6. RVS enhanced monocyte differentiation in thioglycollate-induced peritonitis by increasing scavenger receptor expression and activity. Macrophages isolated from mice given RVS responded differently to LPS. These findings demonstrate that RVS confers selective anti-inflammatory activity without causing the overall inhibitory effects on immune cells.
REVIEW | doi:10.20944/preprints202003.0254.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: zebrafish; inflammation; tumour initiation; macrophage; neutrophil; cancer; pre-neoplastic; live imaging; tumourigenesis; tumour model
Online: 16 March 2020 (01:31:28 CET)
The zebrafish is now an important model organism for cancer biology studies and provides some unique and complementary opportunities in comparison to the mammalian equivalent. The translucency of zebrafish has allowed in vivo live imaging studies of tumour initiation and progression at the cellular level thus providing novel insights into our understanding of cancer. Here we summarise and discuss available transgenic zebrafish tumour models and what we have gleaned from them with respect to cancer inflammation. In particular, we focus on the host inflammatory response toward transformed cells during the pre-neoplastic stage of tumour development. We discuss features of tumour associated macrophages and neutrophils in mammalian models and present evidence which supports the idea that these inflammatory cells promote early stage tumour development and progression. Direct live imaging of tumour initiation in zebrafish models has shown that the intrinsic inflammation induced by pre-neoplastic cells is tumour promoting. Signals mediating leukocyte recruitment to pre-neoplastic cells in zebrafish correspond to signals mediating leukocyte recruitment in mammalian tumours. The activation state of macrophages and neutrophils recruited to pre-neoplastic cells appears to be heterogenous, as seen in mammalian models, which provides an opportunity to study the plasticity of innate immune cells during tumour initiation. Although several potential mechanisms are described that might mediate the trophic function of innate immune cells during tumour initiation in zebrafish, there are several unknowns that are yet to be resolved. Rapid advancement of genetic tools and imaging technologies for zebrafish will facilitate research into the mechanisms that modulate leukocyte function during tumour initiation and identify targets for cancer prevention.
ARTICLE | doi:10.20944/preprints202310.1724.v1
Subject: Medicine And Pharmacology, Ophthalmology Keywords: age-related macular degeneration; cell invasion; choroidal neovascularization; macrophage recruitment; recombinant sulfated CXCR3 peptide trap
Online: 26 October 2023 (13:42:13 CEST)
Background and Objectives: Chemokines have various biological functions and potential roles in the development or progression of neuroinflammatory diseases. However, the specific pathogenic roles of chemokines in age-related macular degeneration (AMD), the leading cause of blindness in older individuals, remain elusive. Chemokines interact with their receptors expressed in the endothelium and on leukocytes. The sulfation of tyrosine residues in chemokine receptors increases the strength of ligand–receptor interaction and modulates signaling. Therefore, in the present study, we aimed to construct a human recombinant sulfated CXCR3 peptide trap (hCXCR3-S2) and mouse recombinant sulfated CXCR3 peptide trap (mCXCR3-S2) to demonstrate in vivo effects in preventing choroidal neovascularization and chemotaxis. Materials and Methods: First, the effect of hCXCR3-S was validated in vitro. Interestingly, hCXCR3-S2 inhibited the migration and invasion of two human cancer cell lines. Subsequently, the in vivo efficacy of mCXCR3-S2 was investigated using a mouse model of neovascular AMD. Results: Intravitreal injection of mCXCR3-S2 attenuated choroidal neovascularization and macrophage recruitment in neovascular lesions. These in vitro and in vivo effects were significantly stronger with CXCR3-S2 than with wild-type CXCR3 peptides. Conclusion: These findings demonstrate that the sulfated form of the CXCR3 peptide trap is a valuable tool that could be supplemented with antivascular endothelial growth factors in AMD treatment.
ARTICLE | doi:10.20944/preprints202104.0464.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: tumor-associated macrophage; exosomes; extracellular vesicles; heat shock proteins; oral cancer; fluorescent labeling of exosomes
Online: 19 April 2021 (11:50:52 CEST)
Tumor-associated macrophages are a key component in the tumor microenvironment, secreting extracellular vesicles (EVs) such as exosomes and other various factors for intercellular communication. However, macrophage-derived EVs heterogeneity and their cytotoxicity to cancer cells has not been well understood. Here, we aimed to separately isolate various types of macro-phage-EVs by size exclusion chromatography (SEC) method and investigate EV transmission and cytotoxicity to oral cancer cells. For fluorescence-labeling of cellular and EV membranes, palmitoylation signal-fused GFP and tdTomato were expressed in THP-1 monocytic cells and HSC-3 oral cancer cells, respectively. We found that fluorescence-labeled EVs secreted by macrophages were highly transmissive to oral cancer cells than those from parental monocytic cells. In a co-culture system and conditioned medium (CM), a macrophage-secreted unidentified factor was cytotoxic to oral cancer cells. We fractionated macrophage-derived EVs by the SEC method and performed western blotting to characterize various EV types. Three fractions were characterized: small exosomes (EXO-S: < 50 nm) fraction containing HSP90α, HSP90β, CD63 (EV marker) and β-actin; large exosomes (EXO-L: 50-200 nm) fraction containing CD9 (EV marker) and HSP90β; large EVs (100-500 nm) fraction. Notably, the macrophage-derived small exosomes fraction was cytotoxic to oral cancer cells, while large exosomes and large EVs were not. There-fore, it was implicated that macrophage-derived small exosomes are cytotoxic with high trans-mission potential to cancer cells.
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: hyaluronic acid; biphasic bone substitute; biocompatibility; tissue reaction; inflammation; macrophage; M1; M2; multinucleated giant cells
Online: 28 March 2019 (06:54:57 CET)
Biphasic bone substitutes (BBS) are nowadays established biomaterials. Through their constant development even natural components like hyaluronic acid (HY) are added to improve both their handling and also their regenerative properties. However, low knowledge exists regarding the consequences of the HY addition for their biocompatibility and the inflammatory tissue reactions. Thus, the present study was conducted aiming to analyze the influence of two different amounts of high molecular weight HY (HMWHY) combined with a BBS on the in vitro biocompatibility and the in vivo tissue reaction. Established in vitro procedures using L929 cells were used for cytocompatibility analyses under the test conditions of DIN EN:ISO 10993-5. For the in vivo study part, calvarial defects were created in 20 Wistar rats and subsequently filled with the BBS and the BBS combined with two different HMWHY amounts, i.e., BBS+HY(L) and BBS+HY(H). As controls empty defects were used. Established histological, immunohistochemical and histomorphometrical methods were applied to analyze the tissue reactions to the three different materials, including the induction of pro- and anti-inflammatory macrophages and multinucleated giant cells (BMGCs). The in vitro results showed that none of the materials or compositions caused biological damages to the L929 cells and can considered to be non-toxic. The in vivo results showed that only the addition of high doses of HY to a biphasic bone substitute significantly decreases the occurrence of proinflammatory macrophages (* p < 0.05) comparable to the numbers found in the control group, while no significant differences within the three study groups for M2-macrophages nor BMGCs were detected. In conclusion, the addition of different amounts of HMWHY does not seem to affect the inflammation response to the BBS while improving the material handling properties.
REVIEW | doi:10.20944/preprints202309.0375.v1
Subject: Medicine And Pharmacology, Dermatology Keywords: Burn healing; anti-Gal antibody; -gal epitope; -gal nanoparticles; macrophage migration; -gal therapy; mesenchymal stem cells.
Online: 6 September 2023 (10:23:59 CEST)
Macrophages play a pivotal role in the process of healing burns. One of the major risks in the course of burns healing, in the absence of regenerating epidermis, is infections which greatly contribute to morbidity and mortality in such patients. Therefore, it is widely agreed that accelerating recruitment of macrophages into burns may contribute to faster regeneration of the epidermis and thus, decreasing the risk of infections. This review describes a unique method for rapid recruitment of macrophages into burns and activation of these macrophages to mediate accelerated regrowth of the epidermis and healing of burns. The method is based on application of bio-degradable “alpha-gal” nanoparticles to burns. These nanoparticles present multiple alpha-gal epitopes (Gal alpha1-3Gal beta1-4GlcNAc-R) which bind the abundant natural anti-Gal antibody that constitutes ~1% of immunoglobulins in humans. Anti-Gal/alpha-gal nanoparticles interaction activates the complement system, resulting in localized production of the complement cleavage-peptides C5a and C3a that are highly effective chemotactic factors for monocytes derived macrophages. The macrophages recruited into the alpha-gal nanoparticles treated burns are activated following interaction between the Fc portion of anti-Gal coating the nanoparticles and the multiple Fc receptors on macrophages cell membranes. The activated macrophages secrete a variety of cytokines/growth factors that accelerate the regrowth of the epidermis and regeneration of the injured skin, thereby cutting the healing time by half. Studies on healing of thermal injuries in the skin of anti-Gal producing mice, demonstrated a much faster recruitment of macrophages into burns treated with alpha-gal nanoparticles than in control burns treated with saline and healing of the burns within 6 days, whereas healing of control burns takes ~12 days. alpha-Gal nanoparticles are non-toxic, and do not cause chronic granulomas or keloids. These findings suggest that alpha-gal nanoparticles treatment may harness anti-Gal for inducing similar accelerated burn healing effects also in humans.
REVIEW | doi:10.20944/preprints202308.1104.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: paratuberculosis; in vivo; in vitro; ex vivo; infection model; macrophage; neutrophil; epithelial cell; rabbit; experimental infection
Online: 15 August 2023 (08:47:07 CEST)
Paratuberculosis (PTB) is a chronic granulomatous enteritis caused by Mycobacterium avium subsp. paratuberculosis (MAP) that affects a wide variety of domestic and wild animals. It is considered as one of the diseases with the highest economic impact in the ruminant industry. Despite many efforts and intensive research, PTB control is still controversially discussed and diagnostic and immunoprophylactic tools lack great limitations. Thus, models play a crucial role in understanding the pathogenesis of infection and disease, and in testing novel vaccine candidates. Here, we review the potential and limitations of different experimental approaches currently used in PTB research, focusing on laboratory animals and cell based models. The aim of this review is to offer a vision of the models that have been used and what has been achieved or discovered with each one so that the reader can choose the best model to answer their scientific questions and prove their hypotheses. Also, we bring forward new approaches that we consider worth exploring in the near future.
ARTICLE | doi:10.20944/preprints202305.1550.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: Mycobacterium tuberculosis; mincle; docking; macrophage; cytokine; trehalose dibehenate; trehalose dimycolate; Molegro Studios virtual docker; immune system
Online: 23 May 2023 (03:42:12 CEST)
Mincle, a C-type lectin, is expressed predominantly in macrophages, where it plays a role in the macrophage response to various microorganisms such as mycobacteria. Docking is a computational procedure in which various software packages generate different positions at which ligands bind to their receptors. Discovery Studio docking was used in Molegro Virtual Studios. ChemDraw and ChemDraw3D were used for ligand preparation and construction because the protein preparation performed using docking software was a very lengthy process. Mincle plays a novel and non-redundant role in the induction of inflammatory signaling in response to mycobacteria. One disadvantage of Molegro studio docking is that it does not show the metallic atoms with which it interacts but rather shows hydrogen bonding and amino acid interactions. Hypothetically, trehalose dimycolate (TDM) and trehalose dibenzenate (TDB) detected by macrophages ultimately lead to CARD9 signaling, thereby producing pro-inflammatory cytokines and chemokines that have the potential to be used therapeutically.
REVIEW | doi:10.20944/preprints202103.0219.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Alzheimer’s disease; blood-brain barrier; endothelial cell; laminin; multiple sclerosis; pericyte; perivascular macrophage; sonic hedgehog; vascular smooth muscle cell
Online: 8 March 2021 (13:35:25 CET)
Pericytes are increasingly recognized as being important in the control of blood-brain barrier permeability and vascular flow. Research on this important cell type has been hindered by widespread confusion regarding the phenotypic identity and nomenclature of pericytes and other perivascular cell types. In addition, pericyte heterogeneity and mouse-human species differences have contributed to confusion. Herein we summarize our present knowledge on the identification of pericytes and pericyte subsets in humans, primarily focusing on recent findings in humans and nonhuman primates. Precise identification and definition of pericytes and pericyte subsets in humans may help us to better understand pericyte biology and develop new therapeutic approaches specifically targeting disease-associated pericyte subsets.
REVIEW | doi:10.20944/preprints202309.1647.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: macrophage; inflammation; acetylcholine receptor; cholinergic receptor; polarization, cholinergic agonist; alpha 7 nicotinic acetylcholine receptor; CHRFAM7A, cholinergic machinery, cholinergic anti-inflammatory pathway
Online: 25 September 2023 (09:28:51 CEST)
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.
ARTICLE | doi:10.20944/preprints202304.0587.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: cardiovascular diseases; salivary biomarkers; myocardial infarction; saliva; salivary glands; adiponectin; C-reactive protein; Chemokine CCL3; macrophage inflammatory proteins; periodontitis; inflammation mediators; risk assessment
Online: 19 April 2023 (10:40:14 CEST)
Background: Macrophage inflammatory protein-1 alpha (MIP-1α) and C-reactive protein (CRP) are pro-inflammatory biomarkers that quantify clinical and subclinical inflammation in cardiac ischemia in cardiac inflammation and disease. Adiponectin is an anti-inflammatory marker associated with good health. The susceptibility of periodontitis patients to cardiovascular events needs to be evaluated. Objective: This study aims to assess the levels of biomarkers in periodontitis patients with and without acute myocardial infarction (AMI) compared to controls. Material and methods: Pro-inflammatory and anti-inflammatory analytes were examined by collecting unstimulated saliva from three groups (n = 20/each): healthy individuals, individuals with stage III periodontitis, and post-myocardial infarction patients with stage III periodontitis. The samples were collected within 48 hours of AMI. Results: Adiponectin levels were significantly lower in patients with periodontitis with and without AMI compared to controls, while CRP and MIP-1α were significantly higher in patients with periodontitis with and without AMI compared to controls. The highest titers for MIP-1α and CRP were detected among patients with periodontitis with and AMI. Conclusion: Our study provides evidence of the association between periodontitis and salivary analytes that occur in tandem with cardiovascular disease. The lower levels of Adiponectin and higher levels of CRP and MIP-1α in patients with periodontitis indicate that this condition is a potential risk factor for cardiovascular disease. The findings emphasize the importance of early detection and intervention for periodontitis patients to prevent cardiovascular events.
REVIEW | doi:10.20944/preprints202007.0314.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: hepatic fibrosis; Mac-2 binding protein glycated isomer; apoptosis inhibitor of macrophage; patatin-like phospholipase domain-containing protein 3; α-fetoprotein; PIVKA-II
Online: 14 July 2020 (13:55:16 CEST)
Nonalcoholic fatty liver disease (NAFLD) is becoming the leading cause of hepatocellular carcinoma (HCC), liver-related mortality, and liver transplantation. There is reasonable epidemiological cohort data to recommend surveillance of patients with NAFLD based upon the incidence of HCC. The American Gastroenterology Association (AGA) expert review published in 2020 recommend that NAFLD patients with cirrhosis or advanced fibrosis estimated by non-invasive tests (NITs) should consider HCC surveillance. NITs include fibrosis-4 (FIB-4) index, the enhanced liver fibrosis (ELF) test, FibroScan, and MR elastography. The recommended surveillance modality is abdominal ultrasound (US) given that it is cost effective and noninvasive with good sensitivity. However, US is limited in obese patients and those with NAFLD. In NAFLD patients with a high likelihood of having an inadequate US or if US is attempted but inadequate, CT or MRI may be utilized. The GALAD score, consisting of age, gender, AFP, lens culinaris-agglutinin-reactive fraction of AFP (AFP-L3), and protein induced by vitamin K absence or antagonist-II (PIVKA-II), can help to identify high risk of incident HCC in NAFLD patients. Innovative parameters including Mac-2 binding protein glycated isomer , type IV collagen 7S, free apoptosis inhibitor of macrophage, combination of single nucleoside polymorphisms are expected to be established. Considering a large number of NAFLD population, optimal screening tests must meet several criteria including high sensitivity, cost effectiveness and availability.
ARTICLE | doi:10.20944/preprints202111.0018.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Newcastle Disease Virus (NDV); NDV ZG1999HDS; NDV La Sota; TLT (Human macrophage cell line; Immunomodulation; Anti - Gram Positive bacteria; Anti - Gram - Negative bacteria; activity
Online: 1 November 2021 (13:01:38 CET)
ABSTRACT. The immunotherapies, as a modern therapeutic approach, get an attention because of theirs’ promise to treat a large number of different medical disorders. Immunomodulation effects of low titres (10 HA/ml) of NDV (Newcastle Disease Virus) ZG1999HDS or La Sota were tested on TLT (Human macrophage cell line) bound to PBMC (Peripheral Blood Mononuclear Cells). During the immunomodulation, the amount of NO, H2O2, lysozym and induced antibacterial activity against Gram - positive bacteria (Staphylococcus aureus, MRSA, Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus mutants) and against Gram - negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis and Acinetobacter baumanii) were analysed. In addition, the cytokine secretion, IL-1α, IL-2, IL-4, GM-CSF, TNF-α, IFN-α and IFN-α were evaluated. Firstly, the TLT cells are activated through the NDV ZG1999HDS or La Sota binding, followed by the NO “burst” and H2O2 and lysozyme level increase. Secondly, after the binding to the TLT cells and interaction with the PBMCs, the decrease of GM-CSF, and an increase of TNF – α and IFN – γ were found. Simultaneously, the decrease of pro – inflammatory cytokine IFN-α and the differentially increase of IL-1α, IL-2 and IL-4 were recorded. During the induction of the antibacterial response, against Gram - positive bacteria (Staphylococcus aureus, MRSA, Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus mutants) the effect was one third higher with NDV ZG1999HDS compared to La Sota. Antibacterial response against Gram - negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis and Acinetobacter baumanii) was not so clear. In general, NDV ZG1999HDS or La Sota activated TLT cells, further bound to PBMC; the ZG1999HDS is stronger immunomodulator than La Sota.
REVIEW | doi:10.20944/preprints202005.0244.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: COVID-19; SARS-CoV-2; antigen; monovalent; oligovalent; protein; kilodalton (kDa); Th1 response; Th2 response; B cell activation; B cell receptor (BCR); macrophage; dendritic cell; apoptosis; subcapsular sinus; immunoglobulin; interleukin; cytokine; Cytokine Storm Syndrome (CSS); allergen; immune paralysis; vaccine; polymer
Online: 14 May 2020 (15:19:53 CEST)
COVID-19 sepsis immune response remains unclear. Here we propose a new perspective in host response against pathogenic proteins that may lead to a vaccine design by polymerization of antigens of <70 kDa. In COVID-19, initial Th1 response kills infected cells releasing viral proteins. SARS-CoV-2 viral structural proteins are Spike (140 kDa), Nucleocapsid (50 kDa), Membrane (25 kDa) and Envelope (10 kDa). B cell receptor cannot capture antigens >70 kDa. The Spike protein (140 kDa) cannot be captured by B cells and triggers inflammatory Th1 response via the macrophages. Only proteins with a size <70 kDa can activate B cell receptor and trigger Th2 adaptative humoral response. Moreover, M-25 kDa and E-12 kDa glycoproteins can activate IgM-BCR like oligovalent or monovalent antigens. The sustained infected cells lysis overfeeds high levels of viral proteins <70 kDa, increases B cells activation and, in the shift from Th1 to Th2 immune response, triggers the cytokine storm. The continuous BCR activation increases IL-10 releasing and may lead to immune paralysis.
REVIEW | doi:10.20944/preprints202008.0696.v1
Subject: Biology And Life Sciences, Virology Keywords: COVID-19; SARS-CoV-2; neurotropic virus; Blood-nervous system barrier; bloodcerebrospinal-fluid-barrier; blood-brain-barrier; blood-nerve barrier; olfactory route; Lymphatic brain drainage route; Peripheral nerve or neuronal retrograde route; Macrophage/monocytes cargo route; Double membrane vesicles cargo route; nicotinic acetylcholine receptor
Online: 31 August 2020 (04:43:34 CEST)
Without protective and/or therapeutic agents the SARS-CoV-2 infection known as coronavirus disease 2019 (COVID-19) is quickly spreading worldwide. It has surprising transmissibility potential, since it could infect all ages, gender, and human sectors. It attacks respiratory, gastrointestinal, urinary, hepatic, and endovascular systems and can reach the peripheral nervous system (PNS) and central nervous system (CNS) through known and unknown mechanisms. The reports on the neurological manifestations and complications of the SARS-CoV-2 infection are increasing exponentially. Herein, we enumerate seven candidate routes, which the mature or immature SARS-CoV-2 components could use to reach the CNS and PNS, utilizing the within-body crosstalk between organs. The majority of SARS-CoV-2 infected patients suffer from some neurological manifestations (e.g., confusion, anosmia, and ageusia). It seems that although the mature virus did not reach the CNS or PNS of the majority of patients, its unassembled components and/or the accompanying immune-mediated responses may be responsible for the observed neurological symptoms. The viral particles and/or its components have been specifically documented in endothelial cells of lung, kidney, skin, and CNS. This means that the blood-endothelial-barrier may be considered as the main route for SARS-CoV-2 entry into the nervous system, with the barrier disruption being more logical than barrier permeability, as evidenced by postmortem analyses.