CTL 68H7–819 recognizes a male-specific minor histocompatibility (H-Y) antigen presented by HLA-B*2705. (A) ⁵¹Cr release assay at the indicated effector-target (E/T) ratios showing cytolytic activity of CTL 68H7-819 against donor- and recipient-derived EBV-LCLs, recipient-derived unfractionated PBMCs and PHA-stimulated T-cell blasts, and donor- and recipient-derived dermal fibroblasts. (B) ⁵¹Cr release assay at E/T 5:1 showing cytolytic activity of CTL 68H7-819 against a panel of EBV-LCLs derived from unrelated male and female individuals who shared a single MHC class I allele with the donor-recipient pair from which CTL 68H7-819 was isolated. The shared MHC class I allele and sex of the individual is indicated.