library_construction_protocol: Subcutaneous B16 tumours were implanted on the back mice. On day 13 after tumours were injected, tumors were collected, weighed and chpped before chemical and mechanical digestions with Tumour Dissociation Kit II (Myltenyi) and gentleMACS DIssociator (Myltenyi) using the m-TDK-1 program. Immune cells were isolated by density centrifugation with Lympholyte (Cederlane Labs) followed by positive selection for CD45+ cells (Myltenyi) Library was performed according to the manufacter's instructions (single cell 5' v1 protocol or 5' v2.2 protocol, 10x Genomics).