Mucosal Immunity in Sexually Transmitted Infections

Abstract

Quantitative evaluation of the cells involved in the immune system, such as lym‐ phocytes, plasma cells, macrophages, dendritic cells, and epithelial cells, together with their products, including antibodies, cytokines, and humoral factors of innate immunity, convincingly revealed that the immune system associated with the mucosae is greater than its systemic counterpart (Russell et al. 2015a). This fact should not be surprising, as the development of the entire immune system during evolution and continuously in everyday life is driven by stimulation with commensal microbiota, antigens present in food and inhaled air, as well as path‐ ogens throughout the enormous surface area of mucosal sites, which far exceeds the skin surface. The mucosal immune system comprises anatomically remote and physio‐ logically distinct compartments that provide protection at various mucosal sites. Although the genital tract shares some common features with other mucosae, including the presence of humoral factors and cells of innate immunity, and the origin of cells involved in antibody production and T cell‐mediated immunity, there are also many distinct features characteristic of the genital tract (Russell and Mestecky 2002, 2010; Mestecky et al. 2005). The spectrum of antigens including commensal or pathogenic microorganisms, and sperm is different from those at other mucosal sites. Furthermore, the primary physiological role of the genital tract is reproduction, which involves the acceptance of allogeneic sperm and semi‐allogeneic offspring. This distinct physiological role influences the immune system of the genital tract with respect to the induction or suppression of immune responses, which must be considered in the development and application of vaccines against infectious agents of sexually transmitted diseases. Mucosal Immunity in Sexually Transmitted Infections Jiri Mestecky and Michael W. Russell