Mitogen and antigen stimulation of multiple sclerosis cerebrospinal fluid lymphocytes in vitro.

Responses of cerebrospinal fluid (CSF) and peripheral blood (PB) lymphocytes from 20 MS patients to phytohemagglutinin (PHA), measles, rubella, mumps and herpes simplex virus antigens were followed during periods of from 6 to 13 months. Up to 6 examinations, each with 1-5 stimulants, were performed with a lymphocyte blast transformation test. Most of the patients responded with their CSF cells to PHA (14/19) and at least to some of the viral antigens tested (15/20) during the follow-up. Although the maximal responses of CSF and PB cells to PHA and measles virus antigen were of the same magnitude, non-reactive or weakly responding lymphocytes were more common in CSF than in PB. In 7 of 15 patients having viral antigen responsive CSF cells simultaneous reactivity to several antigens could be shown. The stimulation results of CSF lymphocytes did not correlate with the numbers of CSF leukocytes or the intrathecal IgG synthesis. A negative correlation was observed between the strength of the CSF cellular response to PHA or measles virus antigen and the rate of intrathecal antibody synthesis to measles virus antigen, suggesting that the stimulated cells may at least partially represent suppressor cells.