HLA-restricted lysis of AML by minor H antigen–specific T-cell clones. AML samples that were matched and mismatched at the HLA-restricting allele with individual minor H antigen–specific T-cell clones were labeled with CFSE and incubated for 12 hours with minor H antigen–specific CTL clones at an ET ratio of 20:1. Lysis of CFSE-labeled AML cells was determined by FACS analysis to allow analysis of leukemia cells. (A) Lysis of AML by HLA-A24–restricted CTL clone I 19.2 and HLA-B7–restricted CTL clone K 9.3. (B) Lysis of AML by HLA-B8–restricted CTL clone J 47 and HLA-B7–restricted CTL clone S 44.2. (C) Lysis of AML by HLA-B8–restricted CTL clone J 7 and HLA-B44–restricted CTL clone R 29. (D) Lysis of AML by HLA-A2–restricted CTL clone M 56 and by HLA-B35/C4–restricted CTL clone R 7. The data are representative of multiple independent experiments for each CTL clone.