Fig. 7: Targeting Itgβ8 in melanoma patients impairs TGF-β signaling and increases cytotoxic functions in tumor-infiltrating CD8^pos T cells.

Fresh serial sections from the same melanoma for each patient were maintained in culture conditions in the presence or not of neutralizing anti-Itgβ8 antibody as illustrated in (a). b–e Forty-eight hours later, CD8^pos T cells infiltrating the tumors were analyzed by flow cytometry as illustrated in (b). c Representative histograms of the levels of phosphorylated SMAD2/3 (p-SMAD2/3) in tumor CD8^pos T cells in the response to anti-Itgβ8 antibody treatment. Percentages of cells with high levels of phosphorylation of SMAD2/3 are indicated. d Graph illustrates the percentage of CD8^pos T cells positive for p-SMAD2/3 in response to treatment. Each gray dot illustrates the value for tumor CD8^pos T cells in the absence of treatment and the linked red dot that of CD8 T cells from the same tumor after anti-Itgβ8 antibody treatment. e Representative histograms of the levels of granzyme B (GzB) in tumor CD8^pos T cells in the response to anti-Itgβ8 antibody treatment. Percentages of cells producing high levels of GzB are indicated. f Graph illustrates the percentage of CD8^pos T cells positive for both GzB and CD107 in response to treatment. Each gray dot illustrates the value for tumor-infiltrating CD8^pos T cells in the absence of treatment and the linked red dot that of CD8^pos T cells from the same tumor after anti-Itgβ8 treatment. n = 6–7 different patients, *P < 0.05 was determined by two-tailed Wilcoxon test. d P = 0.0313 (*), f P = 0.0156 (*). Source data are provided as a Source Data file.