CD4 and systemic lupus erythematosus: Sirtuin 1 (SIRT1) mRNA levels were enhanced, while mRNA levels of HDAC2, HDAC7, P300, cyclic AMP response element-binding protein (CBP), enhancer of zeste homolog 2 (EZH2), and suppressor of variegation 3-9 homolog 2 (SUV39H2) were reduced in CD4+ T cells from active SLE patients.