Fig. 4.

Suppressive function of CD8⁺Foxp3⁺ T cells in vitro. a CFSE-labeled CD4⁺ T cells were cultured alone or with sorted CD8⁺CD25⁺ T cells from TIL of GC patients at 1:1 for 5 days in the presence of anti-CD3 and anti-CD28 antibodies. The suppressive effect of CD8⁺CD25⁺ T cells on the proliferation and IFN-γ production of CFSE-labeled CD4⁺ T cells was detected by flow cytometry. A representative flow cytometry analysis is shown from one of two patients. b CD8⁺Foxp3⁺ T cells were induced by TGF-β1 (10 ng/ml) for 5 days and then isolated by sorting CD8⁺CD25⁺ T cells. CFSE-labeled CD4⁺ T cells were cultured alone or with sorted TGF-β1-induced CD8⁺CD25⁺ T cells at 1:1 for 5 days in the presence of anti-CD3 and anti-CD28 antibodies. A representative flow cytometry analysis for the proliferation and IFN-γ production of CFSE-labeled CD4⁺ T cells is shown from one of three independent experiments