CD4 and systemic sclerosis: Subsequently, 9112 CpGs were found to be differentially methylated in SSc CD4+ T cells compared to HD (FDR < 0.05 and p value < 0.01), in which 7837 and 1275 CpGs were hyper- and hypomethylated, respectively (Fig. 1c; Additional file 2: Table S2).