Rat anti-Human IL6 Monoclonal antibody, clone NR3-24B6

While extensive literature exists about the role of oral bacterial pathogens likePorphyromonas gingivalisandFusobacterium nucleatumin oral squamous cell carcinoma (OSCC), the role of health-associated species has been largely unexplored. In this study, we assessed the effect ofStreptococcus mitis, Rothia mucilaginosa, Neisseria flavescens, Haemophilus parainfluenzae, Lautropia mirabilis, andVeillonella parvulaon proliferation and expression of marker genes (IL-6, TNF-alpha, MMP3, CD36, CCD1, and NANOG) in OSCC cell lines CAL27, SCC25, and SCC4.Porphyromonas gingivaliswas included as a pathogenic control. Both bacterial lysates (3 concentrations) and live cells (3 MOIs) were tested.S. mitis, H. parainfluenzae, andN. flavescensresulted in substantial, dose-dependent reduction of proliferation, which was found to be mediated by H(2)O(2)for the former and intracellular infection in the latter two species. However, onlyH. parainfluenzaeshowed differential antiproliferative effect against the cancer cell lines vs. the normal control (TIGKs). In the gene expression assays, the health-associated species mostly downregulated CD36, a gene that plays an important role in tumor growth and metastasis, whileP. gingivalisupregulated it. IL6 and TNF expression, on the other hand, was upregulated by almost all species, particularly the Gram-negatives includingP. gingivalis. The effect on other genes was less evident and varied significantly by cell line. This exploratory study is the first insight into how health-associated bacteria may interact with OSCC. Further studies to explore whether the observed effects may have implications for the prevention or treatment of oral cancer are warranted.

We evaluated the effect of gut bacterial metabolites of polyunsaturated fatty acids on inflammation and found that 10-oxo-cis-6,trans-11-octadecadienoic acid (gamma KetoC) strikingly suppressed LPS-induced IL-6 release from bone marrow-derived macrophages (BMMs), which was accompanied by reduced mRNA expression of Il6, TNF, and Il1b. gamma KetoC decreased the cAMP concentration in BMMs, suggesting that gamma KetoC stimulated G protein-coupled receptors. A Gq agonist significantly suppressed LPS-induced IL-6 expression in BMMs, whereas a Gi inhibitor partially abrogated gamma KetoC-mediated IL-6 suppression. Cytosolic Ca2+ was markedly increased by gamma KetoC, which was partly but not fully abrogated by an ion channel inhibitor. Taken together, these data suggest that gamma KetoC suppresses inflammatory cytokine expression in macrophages primarily through Gq and partially through Gi. gamma KetoC suppressed osteoclast development and IL-6 expression in synovial fibroblasts from rheumatoid arthritis (RA) patients, suggesting the beneficial effect of gamma KetoC on the prevention or treatment of RA. (c) 2020 Elsevier Inc. All rights reserved.