[A new model of multiple sclerosis. Experimental vaccinia infection in the monkey].

Experimental vaccinia infection in immunosuppressed and immunocompetent Rhesus monkeys has been studied for two years. The results show that vaccinia virus induces two forms of infection in the central nervous system, i.e. choriomeningitis and demyelination disease. The first form occurs in immunologically competent animals; the latter can develop in animals with defective immune response associated with an incomplete clearance of virus. These animals exhibit a noncytocidal persistent infection of glial cells, inducing a complex of potentially pathogenic immune mechanisms. Their direct, or by mediators mediated action is capable of damaging myelin sheaths.