SUPPRESSION OF EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS (EAE) BY INTRAPERITONEAL ADMINISTRATION OF SOLUBLE MYELIN ANTIGENS IN WISTAR RATS

Intraperitoneal (i.p.) treatment of Wistar rats with bovine myelin (BM ) or myelin basic protein (MBP) previously to immunization with BM-CFA showed a diminished incidence and severity of experimental autoimmune encephalomyelitis (EAE) (2/13 and 0/7, respectively) when compared wi th rats immunized with BM-CFA (11/17) or i.p. treated with ovalbumin ( 2/4). Concomitantly, animals treated with BM or MBP exhibited a marked reduction of proliferative response to MBP which was highly positive when spleen mononuclear cells from nontreated and ovalbumin treated an imals were assayed. Rats that were treated with MBP before immunizatio n produce IgA, IgM, total IgG and subclasses of IgG, IgG2a, IgG2b, IgG 2c specific for MBP in similar levels than those observed in nontreate d immunized animals. However, a higher incidence and level of IgG1 was observed in MBP treated rats, meanwhile rats i.p. treated with total BM showed a highly reduced humoral response. The herein presented resu lts show that i.p. treatment with low amounts of soluble forms of myel in antigens markedly reduced the clinical symptoms of the disease, the histological alterations, the cellular proliferative response to MBP, and produced changes in the autoimmune humoral response.