Fig. 1.

Leukocyte subset compositions of the peritoneal infiltrates during responses to primary and secondary challenges with cancer cells. TG-induced peritoneal leukocytes were isolated from unchallenged pups of SR/CR lineage and analyzed for the ability to kill S180 cancer cells in vitro as described in Materials and Methods. The pups displaying the SR/CR phenotype were then challenged with i.p. injection of 10⁶ S180 cells for the first time. The responding leukocytes were washed from the peritoneal cavities, stained with the indicated cell surface markers, and profiled with flow cytometry (dark red bars indicate the first challenge). The populations of responding immune cells were also profiled for the second (green bars), third (brown bars), and fourth (orange bars) challenges with S180 cells. Subset percentages of total infiltrates are shown.