Characterization of Interleukin 2-dependent Cytotoxic T-Cell Clones: Specificity, Cell Surface Phenotype, and Susceptibility to Blocking by Lyt Antisera

Abstract

Cytotoxic T-cells were derived from the peritoneal cavity of a C57BL/6 mouse immunized with BALB/c sarcoma Meth A and from the spleens of BALB/c × C57BL/6 F₁ (hereafter called CB6F₁) mice immunized with BALB/c leukemia RL♂1. The cells were cultured in interleukin 2 and cloned by limiting dilution, and their specificity was determined by direct tests and competitive inhibition assays. C57BL/6 anti-Meth A effector cells recognized H-2D^d determinants. CB6F₁ anti-RL♂1 effector cells recognized a unique cell surface antigen of leukemia RL♂1. The specificity was maintained in long-term culture. The cell surface phenotype of the cloned effector cell lines as determined by absorption analysis was Thy-1.2⁺, Lyt-1.2⁺, 2.2⁺, and 3.2⁺. Cytotoxicity was blocked at the target cell level by antisera against H-2D^d, but not H-2D^k or H-2^b, and at the effector cell level by antisera against Lyt-2.2 and 3.2, but not Lyt-1.2, Ly-5.1 or Thy-1.2.