Changes in immune response during responses in MS patients.

Changes in clinical status and in two measures of immune function were followed for 21 months (median) in 106 multiple sclerosis (MS) patients and cohabitant controls. Antibody titers to measles, cytomegalovirus, and herpesvirus 1 and 2, and leukocyte migration inhibition indexes (LMIs) to measles and streptokinase/streptodornase (SKSD) were measured at 3- to 6-month intervals and at time of exacerbation in the index case. There were 36 exacerbations in 25 patients. Mean baseline antibody titers and LMI to measles were higher in cases than in controls. No consistent changes occurred in antibody titers to any of the viruses, non in LMI to SKSD. LMIs to measles were lower in most MS patients during exacerbations than before or after exacerbations. This apparent improvement in cell-mediated immune response to measles only during exacerbations may reflect aberrant immune regulation in MS patients, response to recrudescence of a latent agent, or some other phenomenon as yet undefined.