A blood test for multiple sclerosis based on the adherence of lymphocytes to measles-infected cells.

The increased capacity of lymphocytes from patients with multiple sclerosis to adhere to human epithelial cells persistently infected with measles virus has provided an accurate blood test for multiple sclerosis. When lymphocytes from affected patients were mixed with measles-infected human epithelial cells, the lymphocytes formed rosettes around a mean (+/-S.E.) of 69.2 +/-1.7% of the measles-infected cells. In contrast, lymphocytes from controls, either healthy or with other neurologic and non-neurologic diseases, formed rosettes around a mean of only 28.2+/-2.1% of the measles-infected cells. Of greater importance was the complete absence of overlap between multiple sclerosis and control values, thus indicating the diagnostic potential of the rosetting phenomenon. The severity, duration and activity of the disease had no effect on the degree of rosette formation.