In this study, percentages of CD39(+) Treg and Th17 cells were compared between relapsing-remitting MS patients and controls and were related to the vitamin D status. The Th17 cell population was expanded in about 40% of the MS patients. In MS patients in remission, but not during relapse, a positive association was found between Th17 cell and CD39(+) Treg percentages (r=0.468, p=0.007). Since CD39(+) Tregs have been shown to have Th17 suppressive capacities, we propose that a dysregulated Th17/CD39(+) Treg balance might contribute to disease exacerbation. A clear role for vitamin D in this regulation could not be established.
Peelen, E., Damoiseaux, J. G. M. C., Smolders, J., Knippenberg, S., Menheere, P. P. C. A., Tervaert, J. W., Hupperts, R. M. M., & Thewissen, M. M. G. L. (2011). Th17 expansion in MS patients is counterbalanced by an expanded CD39(+) regulatory T cell population during remission but not during relapse. Journal of Neuroimmunology, 240-241, 97-103. https://doi.org/10.1016/j.jneuroim.2011.09.013