Cellular immunity to myelin basic protein in man and in animal model systems as measured by the macrophage migration inhibition test.

Lymphocytes from patients with neoplastic disease were tested for sensitization to encephalitogenic factor (EF) by the macrophage migration inhibition test. Sensitization to EF was demonstrated in 71% of patients with various forms of neoplastic disease. Sensitization to EF was also demonstrated for 31% of subjects with no evidence of neoplastic disease; these included patients with warts, chronic bronchitis and hernias. In contrast, healthy subjects showed no sensitization to myelin basic protein. These observations suggest that sensitization to EF may not be confined to patients with neoplastic disease. Lymphocytes from hamsters bearing a transplanted virus induced tumour were sensitized to EF prepared from both human and hamster brain. Sensitization was also seen in hamsters infected with influenza virus but not in animals with acute tubular necrosis produced by glycerol treatment. The development of an animal model system provides a method for the investigation of possible mechanisms of sensitization.