CD4 and systemic lupus erythematosus: The non-autoimmune wildtype C57BL/6 (B6) mice with EGR2 deficiency in both T and B cells (CD2-CreEGR2−/−) had late-onset (after 6 months old) lupus-like autoimmune disease, characterized by an accumulation of highly activated CD4+CD44+ T cells and infiltration of IFNγ- and IL-17- producing CD4+ T cells in multiple organs [5].