| First Author | Wang Z | Year | 2020 |
| Journal | Int Immunopharmacol | Volume | 80 |
| Pages | 106242 | PubMed ID | 32014811 |
| Mgi Jnum | J:297797 | Mgi Id | MGI:6479277 |
| Doi | 10.1016/j.intimp.2020.106242 | Citation | Wang Z, et al. (2020) Functional tumor specific CD8 + T cells in spleen express a high level of PD-1. Int Immunopharmacol 80:106242 |
| abstractText | The inhibitory effects of programmed cell death 1 (PD-1) receptor on tumor specific T cells were mainly investigated at tumor site. While PD-1 expression can be rapidly unregulated upon T cell activation at lymphoid tissues, little is known about where PD-1 signal exerts its inhibitory function in tumor-bearing host. To address this issue, we assessed the effects of PD-1 on vaccine induced activation of splenic CD8 + T cells in mice. The vaccine consisted of mice CD8 + T cell epitope peptide and poly IC. After vaccination, spleen or tumor tissues were dissociated, IFN-gamma synthesis and PD-1 expression by CD8 + T cells were detected by flow cytometry. We found that CD8 + T cells could be successfully activated in spleen after immunization, characterized by the capability of producing IFN-gamma when encountering relevant peptide. These activated splenic CD8 + T cells also expressed a high level of PD-1. Although PD-L1 expression in spleen parenchyma was also increased after vaccination, PD-1 blockade did not affect the activation of splenic CD8 + T cells, but enhanced the anti-tumor effects of peptide vaccine. This synergetic effect of peptide vaccine plus PD-1 blockade was coupled with increased aggregation of IFN-gamma + CD8 + tumor infiltrated lymphocytes (TILs), rather than CD4 + TILs. The results indicated that for tumor-bearing host, PD-1 pathway exerted its inhibitory function at tumor site and PD-1 expression on the splenic CD8 + T cells correlated positively with IFN-gamma synthesis. |
