J S Schwartz1, S Al-Mot2, M F Endam2, S Alromaih3, J Madrenas4, M Desrosiers1. 1. Department of Otolaryngology - Head and Neck Surgery, McGill University, Montreal, Canada. 2. Centre de Recherche du Centre Hospitalier de l Universite de Montreal (CRCHUM), Montreal, Canada. 3. Department of Otolaryngology -Head and Neck Surgery, Faculty of Medicine King Saud University, Riyadh, Saudi Arabia. 4. Department of Microbiology and Immunology, McGill University, Montreal, Canada.
Abstract
BACKGROUND: Staphylococcus aureus is a frequently implicated pathogen in chronic rhinosinusitis (CRS). S. aureus may promote commensalism by downregulating pro-inflammatory T cell host responses via an IL-10 mediated pathway. This finding, coupled with the observation that S. aureus and CD8+ T cell numbers are inversely correlated in CRS mucosa, suggests that S. aureus may evade immune destruction via IL-10 induction. To support this hypothesis, we evaluated i) whether IL-10 levels differ in CRS compared to controls (CTL) using microarray and immunohistochemistry and ii) whether IL-10 levels correlate with S. aureus and CD8+ T cell levels. METHODOLOGY: Sinus epithelial brush samples from 12 patients undergoing ESS for CRS and 10 CTLs underwent microarray analysis of IL-10 gene expression. Microarray results were verified on simultaneously obtained surgical biopsy samples by immunohistochemistry staining for IL-10. Potential mechanisms were assessed by immunohistochemistry for CD8+ T cells and S. aureus. RESULTS: IL-10 gene expression was significantly higher in CRS vs CTL subjects at the time of surgery. Immunohistochemistry confirmed increased levels of intraepithelial IL-10. A strong inverse correlation was observed between intraepithelial IL-10 and CD8+ T cell levels as was intraepithelial IL-10 and S. aureus. CONCLUSION: Elevated IL-10 levels in sinus mucosa may be a potential pathophysiologic feature of CRS in association with a significant downregulation of host CD8+ T cell levels. While S. aureus is believed to play a role in IL-10 induction, a comparatively weaker relationship between S. aureus and IL-10 levels suggests other bacterial species may also induce IL-10 production as a common survival strategy in CRS.
BACKGROUND:Staphylococcus aureus is a frequently implicated pathogen in chronic rhinosinusitis (CRS). S. aureus may promote commensalism by downregulating pro-inflammatory T cell host responses via an IL-10 mediated pathway. This finding, coupled with the observation that S. aureus and CD8+ T cell numbers are inversely correlated in CRS mucosa, suggests that S. aureus may evade immune destruction via IL-10 induction. To support this hypothesis, we evaluated i) whether IL-10 levels differ in CRS compared to controls (CTL) using microarray and immunohistochemistry and ii) whether IL-10 levels correlate with S. aureus and CD8+ T cell levels. METHODOLOGY: Sinus epithelial brush samples from 12 patients undergoing ESS for CRS and 10 CTLs underwent microarray analysis of IL-10 gene expression. Microarray results were verified on simultaneously obtained surgical biopsy samples by immunohistochemistry staining for IL-10. Potential mechanisms were assessed by immunohistochemistry for CD8+ T cells and S. aureus. RESULTS:IL-10 gene expression was significantly higher in CRS vs CTL subjects at the time of surgery. Immunohistochemistry confirmed increased levels of intraepithelial IL-10. A strong inverse correlation was observed between intraepithelial IL-10 and CD8+ T cell levels as was intraepithelial IL-10 and S. aureus. CONCLUSION: Elevated IL-10 levels in sinus mucosa may be a potential pathophysiologic feature of CRS in association with a significant downregulation of host CD8+ T cell levels. While S. aureus is believed to play a role in IL-10 induction, a comparatively weaker relationship between S. aureus and IL-10 levels suggests other bacterial species may also induce IL-10 production as a common survival strategy in CRS.
Authors: Anastasios Maniakas; Marc-Henri Asmar; Axel E Renteria Flores; Smriti Nayan; Saud Alromaih; Leandra Mfuna Endam; Martin Y Desrosiers Journal: Front Cell Infect Microbiol Date: 2018-05-15 Impact factor: 5.293