Figure 7. CXCL9 and CXCL10 expression correlates with response to PD-1 blockade therapy.

(A) Levels of CXCL9 and CXCL10 in plasma samples from non-responders (NR) (red) (n=10) and responders (R) (blue) (n=18) before (Pre) and after treatment (Post) with anti-PD-1 (closed symbols) or anti-PD-1 plus anti-CTLA-4 (open symbols). Statistical differences were determined by Wilcoxon matched-pairs signed rank test. (B) Identification of four subsets of dysfunctional CD8⁺ T cells within tumors based on the cell surface expression of CXCR3 and PD-1 in melanoma patients (top left panel). Surface expression of Tim-3 and CD28 on different subsets of CD8⁺ T cells (top right panel). Bar graph shows the normalized MFI of Tim-3 and CD28 expression on CD8⁺ T cell subsets (bottom panel). MFI of Tim-3 and CD28 expression on each subset was normalized to the MFI of Tim-3 or CD28, respectively, on the CXCR3⁺ PD-1^low CD8 T cell population in each individual patient. See also Figure S7 and Table S1.