CD4 and systemic sclerosis: PHA stimulation resulted in an increased percentage of early-(CD25+) and late-activated (HLA-DR+) CD4+CD8+ T cells when considering this cell population altogether as well as in T1-like, T1/17-like, and CXCR3−CCR6− (CXCR5− non-Treg) CD4+CD8+ T cells and CD4+CD8+ Tf cells from HC and SSc patients, as shown in Figure 8 and Table S1.