Reduced ABO blood group antibody titers in patients after CD19 CAR-T cell therapy

1.INTRODUCTION With rapid developments in genetic engineering,tumor immunology,and cellular engineering,chimeric antigen receptor T cell(CAR-T)cell therapy has become a novel immunotherapy for oncology and other medical fields.1 The promising results of CD19 CAR-T treating B-cell malignancies were reported.2,3 Simultaneously,there existed many adverse events,the most reported of which including B-cell aplasia,hematological toxicity,cytokine release syndrome(CRS),and immune effector-cell–associated neurotoxicity syndrome(ICANS),3,4 but there is still lack of reports demonstrating the impact of CD19 CAR-T on the ABO blood group potency of patient’s serum.