Experimental allergic encephalomyelitis. Production by myelin basic protein adsorbed on particulate adjuvants.

Abstract

Aqueous solutions of myelin basic proteins do not cause allergic encephalomyelitis (EAE). They were rendered encephalitogenic for rats by admixture with kaolin, talc, glass, uncharged and cation exchange polystyrene resins, carbon and microspheres. Binding of basic protein to some of these aqueous particulate adjuvants was demonstrated spectrophotometrically. Absorption into the lymphatic system was demonstrated histologically. Binding of basic protein to adjuvant can occur in vivo. Basic protein was also bound by a carbon of relatively large particle size. Nevertheless, this carbon and certain other particulates failed to act as adjuvants, probably because they were not absorbed into the lymphatic system. An anion exchange resin, carbonyl iron, and some other particulates were abundantly absorbed into the lymphatic system but exhibited no adjuvant effect with basic protein, even though they do have an adjuvant effect for whole neural tissue. Their lack of effect with the purified antigen was explained by failure to bind basic protein.