CD22, which is also required for the development and differentiation of lymphoblasts, has been offered as an alternative CAR T-cell target for treating r/r B-ALL for patients who are unsuited for CD19 CAR T-cell therapy or relapse cases due to the loss/downregulated expression of CD19 on the cell surface [6]. The gene discussed is CD19; the disease is precursor B-cell acute lymphoblastic leukemia.