A preclinical murine lung cancer model using intrathoracic injection (14, 15) of the Kras-mutated, Tp53-deficient lung cancer cell line KP9-3 (16) demonstrated that ABx treatment reduced CXCL9 production in the lung TME and hampered CXCR3+CD8+ T cell infiltration induced by anti–PD-1 blocking antibodies, leading to reduced efficacy of anti–PD-1–blocking treatment. The gene discussed is CD8A; the disease is lung cancer.