FIGURE 5.
TGF-β1 suppresses GM-CSF and TNF-α secretion by activated effector memory CD8 T cells. Effector memory CD8 T cells were activated in the absence of exogenous TGF-β1 for 10–14 days as described in Fig. 5 and restimulated with HLA-A2+ melanoma cell lines (MEL-526 and MEL-624) or T2 cells pulsed with 1 μM g209 peptide in a 24-h coculture. Cell-free supernatants were quantified for GM-CSF (A) and TNF-α (B) levels using proteomic arrays. Cytokine secretions in response to HLA-A2− melanoma cell lines (MEL-888) or T2 pulsed with irrelevant peptide (g280) represent the nonspecific secretion.