Liposomes containing myelin basic protein (BP) suppress but do not induce allergic encephalomyelitis in Lewis rats

The ability of rats to respond immunologically to myelin basic protein (BP) incorporated into liposomes was tested. BP-liposomes administered intradermally or intravenously to naive rats were non-encephalitogenic, did not induce antibody or cellular reactivity to BP, nor did they protect against a subsequent challenge with BP in complete Freund's adjuvant (CFA). Intravenous administration of BP-liposomes to sensitized rats, however, suppressed EAE if given shortly before the expected onset of clinical signs. The same dose of BP in saline fails to suppress the appearance of clinical experimental allergic encephalomyelitis (EAE).