RELAPSING EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS IN THE SJL-J MOUSE

Abstract

A single injection dose-response curve was done in the SJL/J mouse using varying amounts of syngeneic spinal cord homogenate and Mycobacterium tuberculosis H37RA in a Freund''s type of adjuvant. Inoculation with as little as 0.025 mg of cord homogenate induced severe experimental allergic encephalomyelitis in some mice. Possible reasons for the great ease of induction of experimental allergic encephalomyelitis with this single injection regimen in comparison with other single injection schemes are discussed. No single injection dose combination was found that induced severe experimental allergic encephalomyelitis in all of a group of mice. When 2 injections 1 wk apart were given, all mice so injected developed severe experimental allergic encephalomyelitis, all had relapses, and 9 of 10 had multiple relapses. The number of relapses and severity of residual neurologic deficits were much greater in the 2-injection group than in the single injection group.