Identification of class I MHC-restricting elements for four representative CD8⁺ minor H antigen-specific CTL clones. Each CTL clone was assayed for lytic activity against a panel of EBV-LCL target cells derived from unrelated individuals each of whom shared only one class I MHC allele with the donor/recipient pair from whom the clone was derived. Lytic activity at an E:T ratio of 20:1 against recipient-derived LCL, donor-derived LCL, and LCL derived from unrelated individuals who shared the indicated HLA-A or HLA-B allele with the recipient and the donor is plotted for (A) HLA-A3–restricted clone DRN-7, (B) HLA-B7–restricted clone DRN-11, (C) HLA-B8–restricted clone MRR-2, and (D) HLA-B53–restricted clone DJG-24.