CD7 and acute lymphoblastic leukemia: knocked out CD7 and the T-cell receptor alpha chain (TRAC) of T cells by CRISPR–Cas9, and CD7 CAR-T cells showed antileukemia efficacy against T-ALL cell lines MOLT-3, MOLT-4, HSB-2, and CCRF-CEM without graft-versus-host-disease (GVHD) (81).