CD19 and systemic lupus erythematosus: Briefly, in a clinical trial of BCMA-CD19 compound CAR-T cells (cCAR) for SLE and lupus nephritis (LN), cCAR was well-tolerated, with only mild cytokine release syndrome observed [15].12/13 cCAR-treated patients achieved a reduction in SLE Disease Activity Index 2000 (SLEDAI-2K) score from 10.6 at baseline to 2.7 3 months post-cCAR, and 9/13 patients achieved complete symptom and medication-free remission, with significant improvements in renal function in 10/13 patients.