PDCD1 and neoplasm: Notably, we found that the combination treatment of RFA plus sequential HLCaP NRs fixation and anti-PD-1 injection could significantly promote the frequencies of tumor-infiltrating CD3+CD8+ and CD3+CD4+ T cells (Fig. 6f and Supplementary Fig. 24) inside the distant tumors, but only slightly affected the intratumoral frequency of immunosuppressive regulatory T cells (Tregs) (Fig. 6g and Supplementary Fig. 25).