RAG2^−/−x γc^−/− mice are more susceptible to MCA-induced sarcomas than syngeneic RAG2^−/− and WT mice. The indicated dose of MCA was injected into the subcutaneous space of mice, and sarcoma formation was monitored over time. All cohorts consisted of 20 mice. Tumor-positive mice were defined as those that harbored a progressively growing mass ≥25 mm². Similar results were found in a repeat experiment that included the 5 and 25 µg doses.