CD4 and systemic lupus erythematosus: Inhibiting CD4+ T cell Dnmt1 during mitosis prevents methylation of newly synthesized DNA in the daughter cells, causing demethylation and overexpression of genes that convert normal, antigen specific “helper” T cells into autoreactive, proinflammatory, cytotoxic cells that are sufficient to cause lupus-like autoimmunity in murine models [8].