On day 60 after infection, recipients were subcutaneously engrafted with syngeneic MC38 colon adenocarcinoma cells and tumor-infiltrating P14 CD8+ and SM CD4+ T cells, and TBYS populations were analyzed on days 10, 15 and 20 after tumor engraftment (Fig. 1a and Extended Data Fig. 1a). Here, CD4 is linked to infection.