CD4CD25 cells inhibit killing and attraction of NK cells in the peritoneal model

(A) B16FasL cells (2 × 10) were injected into B6 mice, and 24 h later the peritoneum was lavaged and cells counted. Lavaged cells (10) were added to 10 Cr-labelled B16F10 cells in the presence of 10 purified CD4CD25 or CD4CD25 T cells. Controls included lavaged cells (effectors) alone and CD4CD25 cells without effectors. The supernatant was collected 5 h later and analysed on a beta counter. Means were calculated from triplicates. (B) CD4CD25or CD4CD25 cells (2 × 10) were injected i.p. concomitantly with 2 × 10 B16FasL. Peritoneal cells were recovered 18 h later and used as effectors in a killing assay (as above) against B16F10 at different effector to target ratios. This was repeated in a second experiment (three mice per group in each experiment). (C) B6 mice were depleted of CD25 cells, NK cells or both CD25 cells and NK cells. Treatment with the Ab GL113 served as a control (no depletion). The mice were rested until the depleting Ab PC61 had disappeared from the serum and were then injected i.p. with B16FasL cells. Peritoneal cells were used as effectors cells as in (A). (D) NK1.1CD3 cells were evaluated by FACS. Shown are two separate experiments: In the left panel, recipient mice were RAG (=2 per group), and in the right panel, recipient mice were B6. Data are representative of two separate experiments with a minimum of five mice per group. Statistical analysis was performed using the two-tailed Mann-Whitney test with Prism software (**<p><b>Copyright information:</b></p><p>Taken from "Regulatory T cells inhibit Fas ligand-induced innate and adaptive tumour immunity"</p><p></p><p>European Journal of Immunology 2007;37(3):758-767.</p><p>Published online Jan 2007</p><p>PMCID:PMC2435420.</p><p>Copyright © 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim