As reported by Spitzer et al., in addition to localised anti-tumourimmune responses, a broader systemic analysis is required to evaluate the efficacyof immunotherapies in cancer.28 We speculate that the source of increased levelsof IFN-γ, M-CSF and CXCL1 in CD8+ T cell depleted micetreated with STING agonist could potentially be NK cells or antigen presenting cellsor other myeloid-derived cells. The gene discussed is CD8A; the disease is cancer.