Generation of HLA class I reduced primary human T cells. (A) Experimental scheme showing concept of HLA class I reduction through single HLA allele targeting. (B) Characterization of 6-1 (A2) KO T cells (in which all HLA class I molecules were targeted except for HLA A2) compared with B2M KO T cells; left: HLA BC⁻ population pregated on living CD8⁺ T cells, second from left: β2m expression of HLA BC⁻ and HLA BC⁺ populations pregated on living CD8⁺ T cells; second from right: HLA A2 and HLA A3 expression pregated on HLA BC⁻ CD8⁺ living T cells; right: β2m expression of HLA BC⁻ subsets as defined in dot plots second from right.