GONADAL-HORMONES INFLUENCE THE IMMUNE-RESPONSE TO PLP-139-151 AND THECLINICAL COURSE OF RELAPSING EXPERIMENTAL AUTOIMMMUNE ENCEPHALOMYELITIS

Females have an increased incidence of multiple sclerosis (2:1). This gender dimorphism can be studied effectively using a murine model of r elapsing experimental autoimmune encephalomyelitis (R-EAE). We demonst rated previously that male SJL mice immunized with proteolipid protein (PLP) peptide 139-151 developed an initial episode of paralysis, but failed to relapse. In the present study, clinical EAE relapses were in duced by orchidectomy. Relapses in castrated mice were accompanied by an influx of activated CD4(+), Th1 cells into the CNS which were absen t in sham mice. Our data suggests an important regulatory role for and rogens on the immune response to PLP 139-151 and the clinical course o f R-EAE. (C) 1998 Elsevier Science B.V.