HORMONAL-REGULATION OF T-CELL SUBSETS IN THE OVIDUCT - AN IMMUNOHISTOCHEMICAL STUDY USING SEX-HORMONE-TREATED CHICKEN

The present immunohistochemical study deals with dynamic alteration of T-cell subsets in the oviduct in sex-hormone-treated chickens. Monocl onal antibodies (CT3, CT4, and CT8) specific for the chicken homologue s of CD3, CD4, and CD8 were used in estrogen- or progesterone-treated chickens. In control animals, no lymphocytes appeared throughout the o viduct until 4 weeks of age. When 7-day-old chickens were injected wit h either diethylstilbestrol (DES) or DES plus progesterone, T cells im munoreactive for CT3 first infiltrated the oviduct at 12 hr after the hormone treatment. Their frequency of occurrence rose from 48 to 96 hr . Subsequently, CT3(+) cells in the magnum declined in number per area coincident with the proliferation of albuminous glands in the lamina propria, while in the vagina no decline of T cells was observed. The p opulation of T-cell subsets in the lamina propria of both the magnum a nd vagina was significantly higher in the DES-treated chickens than in DES plus progesterone-treated chickens. Among T-cell subsets, CT8(+) cells were more numerous than CT4(+) cells throughout the study, this relative frequency being shared by normal adults. Depopulation of lymp hocytes from the thymus, spleen and cecal tonsil, their mobilization t o the circulating blood, and subsequent dynamic infiltration into the oviduct suggested that the sex hormones induced the traffic of T cells from the lymphoid organs into the oviduct.