B-cell acute lymphoblastic leukemia is the most common type of leukemia and the prognosis of relapsed/refractory B-ALL is poor. Chimeric Antigen Receptor-transduced T cell (CAR-T) therapy is one of revolutionary targeted immunotherapy. CD19 CAR-T is the most commonly used engineered T cell in B-ALL. The treatment effect is significant and far more than traditional therapy in relapsed/refractory B-ALL. However, the remission time after CD19 CAR-T infusion is short.CD19-positive and CD19-negative B-ALL relapses after CD19 CAR T-cell treatment have occurred in some patients The cause of relapse after CAR-T infusion is minimal residual disease (MRD) which will induce CD19 negative relapse. CD20/CD22/CD10 is still expressed in CD19 negative B-ALL cells which means these CD molecules may become new targets in treatment of CD19 negative relapse of B-ALL. Thus sequential treatment with CD20/CD22/CD10-CART after CD19-CART treatment in relapsed/refractory B-ALL will kill and eliminate CD19 negative B-ALL cells and prolong the remission time.
CD19-negative B-ALL relapses after CD19 CAR T-cell treatment have occurred in some patients. CD20/CD22/CD10 is still expressed in CD19 negative B-ALL cells which means these CD molecules may become new targets in treatment of CD19-negative relapse of B-ALL. Thus sequential treatment with CD20/CD22/CD10-CART after CD19-CART treatment in relapsed/refractory B-ALL will kill and eliminate CD19 negative B-ALL cells and prolong the remission time.