The most prominent and serious toxicity of CAR-T cell therapy is cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines such as IL-2, IL-6, TNF-α, IFN-γ, etc., and these cytokines also play a role in the occurrence and development of inflammatory arthritis and other autoimmune diseases (18–20). Here, IL2 is linked to autoimmune disease.