title: Hepatoma cells up-regulate expression of programmed cell death-1 on T cells.
abstract: OBJECTIVE
  To investigate the effect of hepatoma cells on up-regulation of programmed cell death-1 (PD-1), and the function of PD-1 on T cells.
  
  
  METHODS
  HepG2 or HepG2.2.1.5 cells were co-cultured with a lymphoma cell line-Jurkat cells. PD-1 expression was detected by flow cytometry. IL-2, INF-gamma and IL-10 in culture supernatant were detected by enzyme-linked immunosorbent assay (ELISA). Cytotoxic action of T cells was determined by MTT reduction assay-direct mononuclear cell cytotoxicity assay.
  
  
  RESULTS
  The PD-1 expression on Jurkat cells increased by 16.17% +/- 2.5% and 17.43% +/- 2.2% after HepG2 or HepG2.2.1.5 cells were co-cultured for 48 h. The levels of IL-2, INF-gamma and IL-10 in the culture supernatant were 202.9 +/- 53.0 pg/mL, 88.6 +/- 4.6 pg/mL and 63.7 +/- 13.4 pg/mL respectively, which were significantly higher than those (102.9 +/- 53 pg/mL, 39.3 +/- 4.2 pg/mL, and 34.6 +/-13.7 pg/mL) in the control group (P < 0.05). The OD value for MTT assay in the blocking group (0.29 +/- 0.06) was significantly higher than that (0.19 +/- 0.09) in the control group (P < 0.05).
  
  
  CONCLUSIONS
  PD-1 expression on Jurkat cells is up-regulated by hepatoma cells, cytokines and cytotoxic action are elevated after PD-1/PD-L1 is blocked.
authors.affiliation: Department of Infectious Diseases, Center for Liver Diseases, Peking University First Hospital, No. 8, Xishiku Street, Xicheng District, Beijing 10034, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Chen
authors.forename: Xue-Jie
authors.initials: XJ
authors.lastname: Wu
authors.forename: Gui-Qiang
authors.initials: GQ
authors.lastname: Wang
mesh_terms: D015703:Antigens, CD / Q000378:metabolism*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D060890:B7-H1 Antigen; D006528:Carcinoma, Hepatocellular / Q000276:immunology*; D002450:Cell Communication; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D019169:Jurkat Cells; D008113:Liver Neoplasms / Q000276:immunology*; D061026:Programmed Cell Death 1 Receptor; D013601:T-Lymphocytes / Q000276:immunology*; D015854:Up-Regulation
chemical_list: D015703:Antigens, CD; D051017:Apoptosis Regulatory Proteins; D060890:B7-H1 Antigen; C423236:CD274 protein, human; C508609:IL10 protein, human; C508594:IL2 protein, human; D007376:Interleukin-2; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor; D016753:Interleukin-10; D007371:Interferon-gamma