Anti-donor CTL-p in allogeneic chimera (C57BL/6 → C3J/HeJ) generated by transplantation of C57BL/6 Sca-1⁺Lin⁻ cells. Limiting dilution analysis of CTL-P was performed against donor (A) or third-party (B) splenocytes. (•) Irradiated mice transplanted with Sca-1⁺Lin⁻ cells. (□) Irradiated mice not receiving a transplant.