title: [Expression of PD-1/PD-L1 in peripheral blood mononuclear cells in lung cancer patients and its biological significance].
abstract: OBJECTIVE
  To analyze the expression of co-stimulatory molecules PD-1/PD-L1 in peripheral blood mononuclear cells in lung cancer patients, and to explore its biological significance.
  
  
  METHODS
  One hundred and thirty-three lung cancer patients, 25 lung infection patients and 23 healthy donors were enrolled in this study. 100 µl of whole blood from these subjects were collected. Multi-color immunofluorescence staining and flow cytometry were used to detect PD-1/PD-L1 expression. The results were statistically analyzed.
  
  
  RESULTS
  The expression level of CD3⁺CD8⁺ T cells in the lung cancer patients was (38.83 ± 1.74)%, significantly lower than that in the control group [(43.25 ± 3.35)%, P < 0.05]. CD8⁺CD28⁺ T cell subset in the peripheral blood of lung cancer patients was (17.73 ± 1.21)% significantly lower than that of the healthy donors [(27.96 ± 2.72)%, P < 0.01]. The CD8⁺CD28⁻ T cell subset was (21.19 ± 1.92)% in the lung cancer patients, significantly higher than that of the healthy control group [(15.18 ± 2.93)%, P < 0.05]. The expression level of PD-1 on the surface of CD8⁺CD28⁺ T cells was (10.67 ± 1.12)% in the group of lung cancer patients, significantly higher than that of the control group [(5.32 ± 1.58)%, P < 0.01]. It was also found that the expression of PD-1 on CD8⁺CD28⁻ T cells was up-regulated in the group of lung cancer patients (7.46 ± 1.25)%, significantly higher than that of the healthy control group [(2.68+1.07)%, P < 0.01]. The expression level of PD-L1 on CD68⁺ cells in the lung cancer patients was (16.03 ± 2.06)%, significantly higher than that of the healthy control group [(9.32 ± 2.00)%, P < 0.05].
  
  
  CONCLUSIONS
  Up-regulation of PD-1/PD-L1 on peripheral blood cells in lung cancer patients negatively regulates the lymphocytes, inhibits the immune response for killing tumor cells, and promotes tumor development and immune escape.
authors: Central Lab of Clinical Medicine; the Key Laboratory of Infection and Immunity, the Fifth People's Hospital, Suzhou 215007, China.
authors: Ping
authors: P
authors: Xu
authors: Hui
authors: H
authors: Chen
authors: Yong-jing
authors: YJ
authors: Chen
authors: Yan-bin
authors: YB
authors: Chen
authors: Guo-hao
authors: GH
authors: Gu
authors: Mei-ying
authors: MY
authors: Wu
authors: Min-juan
authors: MJ
authors: Wu
authors: Xue-feng
authors: XF
authors: Wang
authors: Email: xueguangzh@126.com.
authors: Xue-guang
authors: XG
authors: Zhang
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000473:pathology; D060890:B7-H1 Antigen / Q000378:metabolism*; D018106:CD28 Antigens / Q000378:metabolism; D017252:CD3 Complex / Q000378:metabolism; D016827:CD8 Antigens / Q000378:metabolism; D018287:Carcinoma, Large Cell / Q000097:blood / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D061026:Programmed Cell Death 1 Receptor / Q000378:metabolism*; D055752:Small Cell Lung Carcinoma / Q000097:blood / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; D018106:CD28 Antigens; D017252:CD3 Complex; D016827:CD8 Antigens; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor