Figure 4.

Flow cytometric analysis of cell frequency ratios. Flow cytometric analysis in patients with disease control more than 6 months or PR to treatment (R) (blue) versus patients with PD or PFS less than 6 months (NR) (red). (A) Line graphs indicate PDL2⁺ monocyte to PDL2⁺ MDSC, CD4 to CD8 T-cell and CD4⁺ to CD8⁺ central memory T-cell ratios are significantly different in R and NR. Line graph represents values at baseline and after initiation of afatinib and pembrolizumab combination therapy. Median values with 75th and 25th percentile whiskers. A mixed effects model was used to calculate the repeated measures p value. (B) Cell ratios of individual patients at baseline presented as column dot plots, PDL2⁺ monocytes to PDL2⁺ MDSC, CD4⁺ to CD8⁺ T-cells, and CD4⁺ to CD8⁺ central memory T-cells. Horizontal lines represent median values. (C) Receiver operator characteristic curve for baseline ratios of PDL2⁺ monocytes to PDL2⁺ MDSC cells, CD4⁺ to CD8⁺ central memory T-cells, and CD4⁺ to CD8⁺ T-cells. Corresponding AUCs of 0.93, 1.00, and 1.00 reveal the utility of cell ratios at baseline as predictors of antitumor activity of therapy. AUC, area under the curve; CD, cluster of differentiation; CM, central memory; MDSC, myeloid-derived suppressor cell; mono, monocyte; PDL2, programmed death-ligand 2.