CD40 and neoplasm: In murine models adoptive transfer tumour‐specific CTL leads to tumour eradication in WT mice, whereas transfer of CTL to CD40 deficient mice did not lead to an effective anti‐tumour immune response.20 Human studies in NSCLC have observed specialised cross‐presenting DC subsets to be blocked at immature developmental stages, thus promoting cross‐tolerance, rather than cross‐priming, of CD8+ T cells.21 Furthermore, other studies have indicated that lung tumor‐infiltrating CD11b+ DCs strongly overexpress PD‐L1, contributing to immunosuppression and tumor growth.22