title: Modification of thymocytes subsets during pregnancy analysed by flow microfluorometry: role of the alloantigenic status of the conceptus.
abstract: Modifications of thymus subsets during pregnancy were monitored using flow microfluorometry and fluorescein-labelled lectins or antibodies. Essentially, it was found that the percentage of peanut lectin-negative (PNA-) cells increased significantly during pregnancy. More interestingly, in the strains tested, the percentage of PNA- cells was more increased in allogeneic than syngeneic pregnancy. This PNA- increase could be mimicked by extracts from syngeneic placenta, but the largest increase in PNA- cells was always observed by injection of allogeneic placental extract, or syngeneic placental extract plus allogeneic cells. These findings suggest that the alloantigenic status of the conceptus does play a role in induction/maintenance of thymus involution, suggesting that it is not a mere hormonal phenomenon and that it could play a role in the events leading to the acceptance of the allogeneic conceptus by the maternal immune system.
mesh_terms: D000818:Animals; D005260:Female; D005333:Fetus / Q000276:immunology*; D005434:Flow Cytometry; D007519:Isoantigens / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011247:Pregnancy; D011270:Pregnancy, Animal; D013601:T-Lymphocytes / Q000166:cytology*
chemical_list: D007519:Isoantigens