To investigate whether long-term in vitro ↑[H+]-maintained CD8+ T cells exhibit enhanced expansion or persistence upon transfer, CD45.1+ OT-I T cells that were expanded in control or ↑[H+]-conditioned medium were adoptively transferred into CD45.2+ C57BL/6N mice with no implanted tumor (Fig. 5a). Here, CD8A is linked to neoplasm.