Immunoglobulin M specific for measles and mumps in multiple sclerosis.

Sera from 43 patients with multiple sclerosis were tested by immunofluorescence. Sera from patients with active multiple sclerosis included four with measles virus-specific immunoglobulin M (measles IgM) and two with mumps virus-specific IgM (mumps IgM). In one case each mumps IgM and measles IgM seem to have persisted for two and a half years and three years respectively. In a comparable group of 43 patients with other nervous diseases measles IgM was found in only one serum, and among 43 normal patients no measles or mumps IgM was found.Herpes simplex virus-specific IgM (herpes simplex IgM) was distributed among all three groups. Anticellular IgM was also found, predominantly in active multiple sclerosis, and persisted in two sera for two and a half years.