Reduced frequency of cTfreg cells in MS patients.
Next, we evaluated the frequency of cTfreg cells, which was determined by selecting FoxP3+CD25+ cells from cTfh cells (Fig. 1). The frequency of cTfreg cells was significantly reduced in MS patients compared to HC (1.38±0.14% vs. 3.0±0.35%, p<0.0001) (Fig. 5a(right panel) ,b), whereas the percentage of non-follicular cTfreg cells did not differ between HC and MS (Fig. 5c and S4a). However, the frequency of cTreg (CD4+FoxP3+CD25+) cells among CD4+ T cells was significantly lower in MS patients compared to HC (1.87±0.29% vs. 3.11±0.35%, p=0.003) (Fig. S4b(left panel) ,c). We also examined the expression of CXCR5+PD-1+ markers in cTreg cells. Interestingly, the percentage of CXCR5+PD-1+ cells among cTreg cells was also significantly reduced in MS patients compared to that observed in HC (13.49±1.48% vs. 25.54±1.8%, p<0.0001) (Fig. S4b(right panel) , d). Taken together, these data suggest that cTfreg cells were down regulated in MS patients.