Moreover, the proliferative activity of stem-like/progenitor exhausted CD8+ T cells was increased (Figure S5D), suggesting that 9D9 promotes the expansion and differentiation of stem-like/progenitor exhausted CD8+ T cells, as recently described for human anti-CTLA-4 antibodies in patients with metastatic melanoma.50 This evidence concerns the gene CTLA4 and metastatic melanoma.