Recently, it has been reported that MPA downregulates histone deacetylases (Histone deacetylase 2 (HDAC2), Histone Deacetylase 7 (HDAC7) and Sirtuin 1 (SIRT1)) and upregulates histone acetyltransferases (CREB Binding Protein (CREBBO) and P300/CBP-associated factor (PCAF)) in CD4+ T cells isolated from systemic lupus erythematosus patients [8]. The gene discussed is SIRT1; the disease is systemic lupus erythematosus.