We used agar overlay assays to assess if 24 circulating and historical isolates of Neisseria mucosa could inhibit the growth of 28 circulating and historical isolates of N. gonorrhoeae. We found no evidence of inhibition by N. mucosa (n=24). Positive controls Streptococcus pneumoniae and Escherichia coli demonstrated a strong inhibitory effect against the growth of N. gonorrhoeae.

Antibiotic-sparing treatments are required to prevent the further emergence of anti-microbial resistance in Neisseria gonorrhoeae. Commensal Neisseria species have previously been found to inhibit the growth of pathogenic Neisseria species. For example, a previous study found that 3 out of 5 historical isolates of Neisseria mucosa could inhibit the growth of N. gonorrhoeae. In this study, we used agar overlay assays to assess if 24 circulating and historical isolates of Neisseria mucosa could inhibit the growth of 28 circulating and historical isolates of N. gonorrhoeae. Although pitting around each colony of N. mucosa created an optical illusion of decreased growth of N. gonorrhoeae, we found no evidence of inhibition (n=24). In contrast, positive controls of Streptococcus pneumoniae and Escherichia coli demonstrated a strong inhibitory effect against the growth of N. gonorrhoeae.

Candida albicans as an opportunistic pathogen exploits the host immune system and causes a variety of life-threatening infections. The polymorphic nature of this fungus gives it tremendous advantage to breach mucosal barriers and cause a variety of oral and disseminated infections. Enterococcus faecalis, another opportunistic pathogen co-exists with C. albicans in several niches in the human body, including the oral cavity and gastrointestinal tract. However, interactions between E. faecalis and C. albicans on oral mucosal surfaces remain unknown. Here, for the first time, we comprehensively characterized the interactive profiles between laboratory and clinical isolates of C. albicans (SC5314 and BF1) and E. faecalis (OG1RF and 846) on an organotypic oral mucosal model. Our results demonstrated that the two species formed robust biofilms on the mucosal tissue surface with profound surface erosion and fungal invasion. Specifically, this effect was more pronounced in the laboratory isolates than in the clinical isolates. Notably, several genes of C. albicans involved in tissue adhesion, hyphal formation, fungal invasion, and biofilm formation were significantly upregulated in the presence of E. faecalis. This study highlights the strain-dependent cross-kingdom interactions between E. faecalis and C. albicans on oral mucosa, demonstrating the requisite to study more substrate-dependent polymicrobial interactions.

As common industrial by-products, airborne engineered nanomaterials are considered important environmental toxicants to monitor due to their potential health risks to humans and animals. The main uptake routes of airborne nanoparticles are nasal and/or oral inhalation, which are known to enable the transfer of nanomaterials into the blood stream resulting in rapid distribution in the body. Consequently, mucosal barriers present in nose, buccal and lung have been identified and intensively studied as the key tissue barrier to nanoparticle translocation. Despite decades of research, surprisingly little is known about the differences among various mucosa tissue types to tolerate nanoparticle exposures. One limitation in comparing nanotoxicological data sets can be linked to a lack of harmonization and standardization of cell-based assays, where a) different cultivation conditions such as air-liquid interface or submerged cultures, b) varying barrier maturity and c) diverse media substitutes have been used. The current comparative nanotoxicological study therefore aims at analyzing the toxic effects of nanomaterials on four human mucosa barrier models including nasal (RPMI2650), buccal (TR146), alveolar (A549), and bronchial (Calu-3) mucosal cell lines to better understand the modulating effects of tissue maturity, cultivation conditions and tissue type using standard Transwell cultivations at liquid-liquid and air-liquid interfaces. Overall, cell size, confluency, tight junction localization, and cell viability as well as barrier formation using 50% and 100% confluency was monitored using trans-epithelial-electrical resistance (TEER) measurements and Presto Blue assays of immature (e.g. 5 days) and mature (e.g. 22 days) cultures in the presence and absence of corticosteroids such as hydrocortisone. Results of our study show that cellular responses to increasing nanoparticle exposures are highly cell type specific, where bronchial mucosal cell barriers models cultivated under ALI conditions showed less tolerance to acute ZnO nanoparticle exposures. Additionally, stronger toxicities are found using early mucosa barriers compared to later barrier models being maturated under air-liquid cultivation conditions.

Background: Understanding in vitro expansion of OKF6/TERT-2 oral epithelial cells is important for studying molecular biology of disease and pathology affecting the oral cavity. The media used for any cell culture is paramount in terms of efficient output. Therefore, this study aims to compare two different media for OKF6/TERT-2 cultures: Keratinocyte Serum-Free Medium (KSFM) and a composite medium comprised of DMEM/F-12 mixed with KSFM (referred to as DFK). For application purposes, this investigation also compares the toxicological effects of flavored electronic cigarette liquids (E-liquids) on OKF6/TERT-2 cultures grown in both media. Methods: Cells were grown in KSFM and DFK media and cellular growth, morphology, gene expression of mucins and tight junctions, as well as wound-healing were determined. Additionally, cellular viability and cytotoxicity were indexed after E-liquid exposures. Results: While overall cellular morphologies remained unaltered, cells grown in DFK reached confluency faster. Except for claudin-1, there is no appreciable difference in expression of the other genes tested. Additionally, cultures in DFK appear more sensitive to E-liquids ± flavors. Conclusions: DFK is an alternative medium for cultivation of OKF6/TERT-2 cells to study molecular biology of disease and pathology, such as their responses to E-liquids ± flavors.

Cell secretome has been explored as a cell-free technique with high scientific and medical interest for Regenerative Medicine. In this work, the secretome produced and collected from Olfactory Mucosa Mesenchymal Stem Cells and Olfactory Ensheating Cells was analyzed and therapeutically applied to promote peripheral nerve regeneration. The analysis of the conditioned medium revealed the production and secretion of several factors with immunomodulatory functions, capable of intervening beneficially in the phases of nerve regeneration. Subsequently, the conditioned medium was applied to sciatic nerves of rats after neurotmesis, using Reaxon^® as tube-guides. Over 20 weeks, the animals were subjected to periodic functional assessments, and after this period, the sciatic nerves and cranial tibial muscles were evaluated stereologically and histomorphometrically, respectively. The results obtained allowed to confirm the beneficial effects resulting from the application of this therapeutic combination. The administration of conditioned medium from Olfactory Mucosal Mesenchymal Stem Cells led to the best results in motor performance, sensory recovery, and gait patterns. Stereological and histomorphometric evaluation also revealed the ability of this therapeutic combination to promote nervous and muscular histologic reorganization during the regenerative process. The therapeutic combination discussed in this work shows promising results and should be further explored to clarify irregularities found in the outcomes and to allow establishing the use of cell secretome as a new therapeutic field applied in the treatment of peripheral nerves after injury.

We wanted to investigate the current knowledge on the impact of diet on anti-TNF response in inflammatory bowel diseases (IBD), to identify dietary factors that warrant further investigations in relation to anti-TNF treatment response, and, finally, to discuss potential strategies for such investigations. PubMed was searched using specified search terms. One small prospective study on diet and anti-TNF treatment in 56 patients with CD found similar remission rates after 56 weeks among 32 patients with good compliance that received concomitant enteral nutrition and 24 with poor compliance that had no dietary restrictions (78% versus 67%, p = 0.51). A meta-analysis of 295 patients found higher odds of achieving clinical remission and remaining in clinical remission among patients on combination therapy with specialised enteral nutrition and Infliximab (IFX) compared with IFX monotherapy (OR 2.73; 95% CI: 1.73–4.31, p < 0.01, OR 2.93; 95% CI: 1.66–5.17, p < 0.01, respectively). In conclusion, evidence-based knowledge on impact of diet on anti-TNF treatment response for clinical use is scarce. Here we propose a mechanism by which Western style diet high in meat and low in fibre may promote colonic inflammation and potentially impact treatment response to anti-TNF drugs. Further studies using hypothesis-driven and data-driven strategies in observational, animal and interventional studies are warranted.