STAT4 and systemic lupus erythematosus: For example, studies have indicated that patients with systemic lupus erythematosus (SLE) carrying the rs7574865 T allele have increased levels of STAT4 mRNA in osteoblasts and peripheral blood mononuclear cells (PBMCs) (47, 48), and when T cells from these patients are stimulated with IL-12 and IFN-α, the levels of STAT4 protein and its phosphorylated form, pSTAT4, are markedly increased (49).