Higher Number of EBI3 Cells in Mucosal Chronic Hyperplastic Candidiasis May Serve to Regulate IL-17-Producing Cells

Previous research into the inflammatory cell infiltrate of chronic hyperplastic candidosis (CHC) determined that the immune response is primarily composed of T cells, the majority of which are T helper (CD4⁺) cells. This present investigation used immunohistochemistry to further delineate the inflammatory cell infiltrate in CHC. Cells profiled were those expressing IL-17A cytokine, EBI3 and IL-12A subunits of the IL-35 cytokine, and FoxP3⁺ cells. Squamous cell papilloma (with Candida infection) and oral lichen planus tissues served as comparative controls to understand the local immune responses to Candida infection. The results demonstrated that Candida-induced inflammation and immune regulation co-exist in the oral mucosa of CHC and that high prevalence of cells expressing the EBI3 cytokine subunit may play an important role in this regulation. This balance between inflammation and immune tolerance toward invading Candida in the oral mucosa may be critical in determining progress of infection.