Roads and detours for CAR T cell therapy in autoimmune diseases

Chimeric antigen receptor (CAR) T cell therapy has been highly effective in eradicating malignant B cells in cancer, and this success has prompted an extension of the approach to areas beyond oncology. In pioneering studies, CAR T cells targeting the B cell marker CD19 demonstrated robust efficacy as treatment for the autoimmune disease systemic lupus erythematosus. Patients who received anti-CD19 CAR T cells experienced remission of most or all clinical manifestations and discontinued prior medications. These results have spurred intense interest in extending these observations to larger patient cohorts and other autoimmune conditions. More nuanced strategies for use of CARs in autoimmunity have also been developed. Here, we offer insight into the role of B cells in the pathophysiology of autoimmunity and present an overview of preclinical studies and clinical trials that use engineered cell therapy for autoimmune disorders. In discussing the prospects and challenges of this emerging field, a view emerges in which the promise of clinical efficacy invites careful consideration of potential pitfalls.