Glucocorticoid Regulation of Mucosal Immunity: Effect of Dexamethasone on IgA and Secretory Component (SC)
Immunoglobulin A (IgA), the predominant immunoglobulin at mucosal surfaces of the body, is produced on a daily basis in amounts greater than all other immunoglobulins combined1. As the first line of defense, IgA at mucosal surfaces protects against bacterial and viral infection by antibody interactions which either destroy pathogens or block their adherence to prevent potentially infective agents from entering the body2. To reach mucosal sites, IgA binds to secretory component (SC), the cytoplasmic portion of the polymeric Ig receptor that is synthesized by rat hepatocytes and epithelial cells lining the mucosal surfaces of the body3–6. Following binding, polymeric IgA (pIgA) is transported from serum into the gastrointestinal tract via bile and from tissues into secretions of the respiratory, gastrointestinal and urogenital tracts7–10. Transport through hepatocytes and epithelial cells is similar in that IgA binds covalently to SC and following endocytosis, is released as pIgA-SC complex (secretory IgA)10–11.
KeywordsHigh Performance Liquid Chromatography Mucosal Surface Female Reproductive Tract Mucosal Immune System Secretory Component
Unable to display preview. Download preview PDF.
- 2.P.C. McNabb and T.B. Tomasi, Host defense mechanisms at the mucosal surface, Ann. Rev. Microbiol. 138:976 (1981).Google Scholar
- 24.C.R. Wira, B. O’Mara, J. Richardson, and R. Prabhala, The mucosal immune system in the female reproductive tract: Influence of sex hormones and cytokines on immune recognition and responses to antigen, Vaccine Research 1:151 (1992).Google Scholar