ANTIGEN-INDUCED INHIBITION OF AUTOIMMUNE-RESPONSE TO RAT MALE ACCESSORY-GLANDS - DISTINCT ROLE OF I-A AND I-E-POSITIVE PERITONEAL-CELLS

The present report describes the structural and functional characteristics of the population of peritoneal cells (PC) from rats injected intraperitoneally (i.p.) 2 h or 24 h previously with a suppressor dose of a purified fraction (FI) of rat male accessory glands (RAG; FI‐PC2h and FI‐PC24h, respectively). Both populations of PC showed the presence of the autoantigens of RAG on their membrane. The study of cell surface marker showed increase of OX17 (I‐E) in FI‐PC2h and OX6 (I‐A) in FI‐PC24h. I.p. injection of FI‐PC2h 10 and 3 days prior to immunization with chemically modified (diazotized arsanilic and sulfanilic acid) RAG (MRAG) in complete Freund's adjuvant induced suppression of the delayed‐type hypersensitivity (DTH) response to MRAG, whereas the i.p. injection of FI‐PC24h induced potentiation of DTH responseto MRAG when compared with controls (animals injected 10 and 3 days prior to immunizationwith PC from rats injected i.p. with an unrelated antigen). The treatment of FI‐PC2h with OX17 and FI‐PC24h with OX6 prior to the transfer blocked the suppression and potentiation described above. These findings show that the i.p. injection of an FI of RAG at a suppressor dose induces PC with immunologically opposite characteristics, depending on the time of obtention. Copyright © 1990 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim