In vitro cellular responsiveness in multiple sclerosis patients to a viral isolate from multiple sclerosis brain tissue and to other antigens.

The Clausen modification of the leukocyte migration test was used to test patients with multiple sclerosis, normal subjects, and patients with other neurologic diseases for cell-mediated immunity to 6/94 virus (a parainfluenza virus previously isolated from the brain tissue of a multiple sclerosis patient), c-RNA virus isolated from a tumor, and the nonviral antigens Candida and purified protein derivative. Leukocytes of multiple sclerosis patient showed significantly less mean inhibition of migration by the 6/94 virus (but not by the c-RNA virus, purified protein derivative, and Candida) than did the cells of normal controls and patients with other neurologic diseases. The relationship of these findings to previous observations in this area and to the pathogenesis of multiple sclerosis is discussed.