PDCD1 and non-small cell lung carcinoma: To assess monocyte heterogeneity in response to anti-PD-1 therapy, we performed mass cytometry on peripheral blood mononuclear cell (PBMC) samples collected from non-small cell lung cancer (NSCLC) patients prior to treatment with anti-PD-1 therapy (n=26 patients), as well as 10 matched patient samples collected after treatment (Figures 1A, B).