The phenotypic distribution of lymphocytes and mononuclear phagocytes resident in rat secretory glands was examined. Isolated exocrine gland mononuclear leucocyte populations contained 50-61% W3/13+ T cells and greater proportions of W3/25+ T helper cells relative to OX8+ T suppressor cells. Surface Ig+ cells (sIg) constituted from 32% to 34% of the cells and their distribution was sIgM greater than sIgA greater than sIgG. The macrophage populations comprised from 0.02% to 0.1% of the unfractionated gland cells. Fractionated secretory gland-adherent cells consisted primarily of non-specific esterase+, phagocytic and Fc receptor-bearing cells. From 35% to 79% of the macrophages in exocrine glands expressed I-A molecules. The results suggest that exocrine glands have the ability to respond locally to an antigenic challenge independently of a central mucosal immune response.
Animals Antigens, Surface