Considering that solid tumours are characterized by a high infiltration of immunosuppressive cells expressing checkpoint molecules such as PD-L1/PD-L2 (refs. 68–70), we showed that Elovl1-deficient CD8+ T cells particularly benefit from anti-PD-1 treatment and synergize with it to unleash their potentiated antitumoural activity, thus mediating tumour reduction. The gene discussed is ELOVL1; the disease is neoplasm.