CHARACTERIZATION OF AN IMMUNOREGULATORY CELL SUBSET INVOLVED IN THE UP-REGULATION OF THE AUTOIMMUNE-RESPONSE TO RAT MALE ACCESSORY-GLANDS

PROBLEM: We studied the regulation of the autoimmune response to rat m ale accessory glands (RAG) using liposomes as adjuvants. METHOD: Adult male Wistar rats were submitted to three intraperitoneal (i.p.) immun izations with 750 mug of saline extract of RAG associated with liposom es. The delayed type hypersensitivity (DTH) response studied approxima tely 10 days after each immunization developed after the first immuniz ation, having a remission state after the second one and a clear incre ase after the third injection. In a further study, spleen mononuclear (SpM) cells obtained form immunized rats 10 days after the third immun ization (DTH positive) or from normal rats were separated as adherent (VV+) or nonadherent (VV-) to Vicia villosa population. In VV+ SpM cel ls from immunized or normal animals an enhanced percentage of OX8+ cel ls (P<.05 and P<.01, respectively) was found, but in VV- SpM cells fro m the same groups of rats an enhanced percentage of W3/25+ cells (P<.0 1 and P<.05, respectively) was found when they were studied by immunof luorescence. Later on, we transferred total VV+ or VV- SpM cells from i.p. immunized rats to immunized recipients 10 days after the second i mmunization (DTH negative). The DTH response was enhanced in recipient s of total or VV+ SpM cells (P<.01). It was also observed that the tra nsfer of VV- SpM cells from immunized rats or total or VV+ SpM cells f rom normal rats did not reduce the suppression state observed after th e second injection (P = NS). The total SpM cells obtained 10 days afte r the third immunization (DTH positive) were able to transfer autoimmu ne response to RAG to normal animals (P<.01), whereas VV+ SpM cells di d not show that capacity (P = NS).