CAR T-cell therapies (such as anti-CD19 CAR Ts for acute lymphoblastic leukemia and large B-cell lymphoma, and BCMA-directed CAR Ts for multiple myeloma) have well-known systemic toxicities like cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Here, CD19 is linked to AL amyloidosis.