Fluctuations in T helper subpopulations in relapsing-remitting multiple sclerosis

Patients with active multiple sclerosis (MS) have been reported to have a depletion of CD4+ CD45R+ cells, the immature resting CD4+ subpopulation. Using Leu 3a(anti-CD4) and Leu 18(anti-CD45R), the frequencies and absolute numbers of CD4+ CD45R+ and CD4+ CD45R- subsets were measured in 30 patients with MS and 17 healthy controls. These subsets were monitored every 6 weeks over a 6 month period. CD4+ CD45R- cells were found to be increased in relapse compared to remission (p less than 0.005) while CD4+ CD45R+ levels were not significantly altered in relapse. However, the CD4+ subset ratio (CD4+ CD45R-/CD4+ CD45R+) was significantly higher in relapse compared with remission (p less than 0.002). Furthermore, these findings were upheld when data from the same 6 patients in relapse and remission was compared. Increased disease activity was not associated with changes in any of the other parameters measured (total T cells, total CD4+ cells, suppressor cells or activated T cells). These results suggest that relapse in MS is accompanied by the conversion of CD4+ CD45R+ resting cells to CD4+ CD45R- primed cells.