CD4 and systemic lupus erythematosus: Based on the above results, we furtherly performed RT-qPCR to investigate the expression of miR-451a level in CD4+ T cells and T cells derived-exosomes of normal individuals and patients with SLE, and it was found that the expression of miR-451a in the CD4+ T cells of patients with SLE was significantly higher (P < 0.01) than that in normal individuals.