INFLAMMATORY CELLS AND MHC CLASS-II ANTIGENS EXPRESSION IN PROSTATE DURING TIME-COURSE EXPERIMENTAL AUTOIMMUNE PROSTATITIS DEVELOPMENT

The degree of lymphocytic infiltration alongside the phenotype of the infiltrating cells and MHC class II expression were studied in rats du ring a time-course experimental autoimmune prostatitis (EAP) developme nt. Inflammatory foci per square millimeter were scarce at day 7 after first immunization (FI) and were composed of few mononuclear cells. T he number of inflammatory foci per square millimeter increased at day 14 and remained with slight variations at days 21 and 28 after FI. The number of mononuclear cells per square millimeter increased on day 14 , diminished slightly on day 21 and reached the highest level on day 2 8. All these infiltrates were constituted by CD4 and CD8 T cells where as only few macrophages were present. Mast cells were also present rea ching maximum levels on day 7 after FI and then decreased. MHC class I I antigens were found in epithelial cells during EAP development. IA s howed a similar pattern in all periods analyzed whereas IE showed a mo dulating behavior, reaching the highest expression on day 21 after FI. In this experimental model, the differential expression of MHC class II antigens could modulate the immune response during EAP development. (C) 1997 Academic Press.