Cell-mediated cytotoxicity against hamster cells transformed by avian sarcoma viruses. 2. Sensitivity of different subclones.

The presence of new antigens on different subclones of hamster cells transformed by avian sarcoma viruses was investigated by an in vitro cellular microcytotoxicity assay. The RS 2/3 and RS 2/10 subclones derived from the RS 2 clone, transformed with a Schmidt-Ruppin strain of RSV were highly sensitive to the cytotoxic action of spleen effector cells obtainled from hamsters immunized with RSV-transformed rat cells. The RS 2/6 subclone was sensitive only when 1,000 target cells were seeded and the RS 2/7 subclone was not susceptible to the cytotoxic action of effector cells. The RB 12/1 subclone, derived from the clone RB 12, transformed with a Bryan strain of RSV was poorly sensitive. The comparison between the sensitivity to XC-sensitized spleen cells of the different subclones and their other known properties was discussed.