Fine specificity of a continuously growing killer cell clone specific for H‐Y antigen

H-Y-specific cytotoxic T cells were first cloned in soft agar and grown over a period of 8 months in media conditioned with supernatants from mouse and rat spleen cells stimulated with concanavalin A. The specificity of cloned cells and their cytolytic potential remained essentially unchanged over the entire culture period. In addition to lysing male target cells expressing H-2Db antigens, the cytolytic cells lysed also male as well as female cells expressing H-2Dd alloantigens. Seventeen out of eighteen subclones derived from the original clone revealed the same activity. The cells divide about every 17--20 h can be obtained in large quantities.