Through methylated CpG-DNA immunoprecipitation (MeDIP), Hedrich CM et al. found that DNA methylation level at the CREMα promoter in SLE CD4+ T cells is lower than healthy controls; moreover, CREMα promoter methylation is reduced in SLE patients who were in active stage compared to the patients in remission [29]. Here, CD4 is linked to systemic lupus erythematosus.