T-cell subset analysis of 3LL tumor growth

We have partially characterized the T-cell subsets that control the growth of the C57BL/6 Lewis lung carcinoma 3LL transplanted into syngeneic mice. By analyzing the phenotypes of anti-tumor lymphocytes generated in vitro and in vivo, we have characterized a CD8 T-cell receptor (TcR) V beta 5,6 positive subpopulation of cytotoxic effectors important in retarding the growth of the transplanted tumor. In contrast, the rejection of 3LL appears to be hindered by the presence of a CD4 V beta II-positive subset since depletion of these lymphocytes in vivo with the appropriate monoclonal antibodies (MAbs) results in significant retardation of tumor growth. These results suggest that the cumulative positive and negative effects of distinct T-cell sub-populations determine the outcome of tumor progression and metastasis.