Figure 6.

In vivo depletion of CD4⁺ or CD8⁺ T cell subsets eliminates regression of TNF-producing tumors. B6 mice received a single i.v. dose of either anti-CD4. anti-CD8 or anti-Thy-1.1 mAb on day 0. Two hours after treatment with mAb, mice were inoculated s.c. with 1 × 10⁷ TNF-producing tumor cells (in experiment 1, TNF-B: in experiment 2. TNF-12) and tumor growth was followed. In both experiments, elimination of CD4⁺ or CD8⁺ cells abrogated the ability of TNF-producing cells to regress. In contrast, animals treated with anti-Thy-l.1 control mAb experienced significant reductions in tumor sizes after an initial phase of tumor growth and 9/12 animals went on to experience complete tumor regression. (^*number with tumor/total at day 28. Tumor area measurements are plotted for each time point and are shown mean ± SEM.)