Specific cytotoxicity of H2^k effectors against H2^b targets. CD8⁺ cells were selected from B10.BR splenocytes and lymph nodes by immunomagnetic beads. Cells were cultured in the presence of IL-2, IL-7, IL-12, and C1498 leukemia cells irradiated to 60 Gy (Boyer49). After 14 days of culture, the effector cells were irradiated between 0 and 30 Gy with a¹³⁷Cs source. The irradiated and nonirradiated effector cells were incubated with nonirradiated C1498 target cells and specific cytotoxicity of the cells was measured with the CytoTox 96 Assay following the manufacturer’s protocol. The mean (±SD) of specific cytotoxicity for quadruplicate samples is shown for E:T ratios of 0.3:1 to 10:1.