PDCD1 and neoplasm: There were no significant differences among untreated and anti-PD-1 therapy-resistant samples in forkhead box P3 (FOXP3)+ CD4+ T cells (regulatory T cells: Treg; Fig. 1c) and two major populations of myeloid cells in the murine models, tumour-associated alveolar macrophages (TAM: CD11c+CD11b−CD103−) and tumour-associated neutrophils (TAN: CD11b+Ly6G+) (Supplementary Fig. 1b).