PDCD1 and neoplasm: Analysis of tumor-infiltrating Vβ13+CD8+ T cells revealed that the superior tumor control and responsiveness to anti-PD1 therapy by CD38lo T cell fraction could be in part due to their increased persistence (Fig. 2Q), better functionality (Fig. 2R), and maintenance of high TCF1 expression (Fig. 2S), compared to CD38hi T cell subset.