CD4 and systemic lupus erythematosus: In a previous study, we observed that CRIF1 deficiency in CD4+ cells increased the frequency of pathogenic Th17 cells by increasing STAT3 phosphorylation; Additionally, B cell-specific deletion of CRIF1 exacerbates lupus severity by promoting the production of IL-17 and IL-6, and CRIF1 overexpression suppresses lupus development in roquinsan/san mice, an experimental lupus model (27).