CD4 and systemic sclerosis: This effect was transversal to all CD4+ T cell subsets (Th1, Th17, Th1/17, CXCR3−CCR6−, Tfr, CXCR5− Treg, and Tfh), from HC and SSc, and was more pronounced for HLA-DR than CD25 (Figure 5 and Table S1).