Fig. 1

Loss of CD27/CD28 expression is present in tumor infiltrating CD8⁺ T cells from HNSCC patients and associates with suppressive function. a. Tumor tissue from four HNSCC patients was dissociated with collagenase/hyaluronidase before staining for FACS analysis. Plots show CD27 and CD28 expression on CD4⁺ (left column) and CD8⁺ (right column) T cells from each patient after gating on CD3⁺ cells. An age-matched donor PBMC stain is included for comparison. b. Tumor-infiltrating CD8⁺ T cells isolated from dissociated tumor tissue from Patient 3 were co-cultured with T cells isolated from peripheral blood (responders) from the same patient and proliferation in response to anti-CD3/CD28 stimulation was determined by Thymidine incorporation. R + R indicates wells where normal responder cells were used as negative control (non-suppressive) cells incubated with responders in similar ratios as the sorted TIL to verify decreased proliferation is due to suppression. Results are presented as average CPM ± SDEV at the indicated TIL:Responder ratio