title: Role of plasmacytoid dendritic cells and inducible costimulator-positive regulatory T cells in the immunosuppression microenvironment of gastric cancer.
abstract: Regulatory T cells (Tregs) and plasmacytoid dendritic cells (pDCs) play important roles in the immune escape of cancer. In this study, we investigated pDCs and pDC-induced inducible costimulator (ICOS)(+) Treg populations in peripheral blood from gastric cancer (GC) patients and healthy donors by flow cytometry. The distribution of these cells in carcinoma tissue, peritumor tissue, and normal gastric mucosa was detected by immunohistochemistry. Plasma and tissue concentration of the cytokines such as interleukin-10 and transforming growth factor-β1 were also measured. We found that the numbers of pDCs, Tregs, and ICOS(+) Tregs in peripheral blood were increased in GC patients compared with healthy donors. In tissue, Tregs and ICOS(+) Tregs were found distributing mainly in carcinoma tissue, whereas pDCs were mainly found in peritumor tissue. Moreover, the Foxp3(+) ICOS(+) /Foxp3(+) cell ratio in carcinoma and peritumor tissue were higher than that in normal tissue. There were more ICOS(+) Tregs in tumor and peritumor tissue of late-stage GC patients. There was a positive correlation between pDCs and ICOS(+) Tregs in peripheral blood and peritumor tissue from GC patients. In conclusion, pDCs may play a potential role in recruiting ICOS(+) Tregs, and both participate in the immunosuppression microenvironment of GC.
authors.affiliation: Department of Gastrointestinal Surgery, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou, China.
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Huang
authors.forename: Xiao-Sun
authors.initials: XS
authors.lastname: Liu
authors.forename: Xian-Ke
authors.initials: XK
authors.lastname: Lin
authors.forename: Hang
authors.initials: H
authors.lastname: Yu
authors.forename: Jian-Yi
authors.initials: JY
authors.lastname: Sun
authors.forename: Xiao-Kun
authors.initials: XK
authors.lastname: Liu
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Hai-Long
authors.initials: HL
authors.lastname: Jin
authors.forename: Ge-Er
authors.initials: GE
authors.lastname: Zhang
authors.forename: Xiao-Xiao
authors.initials: XX
authors.lastname: Shi
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Ji-Ren
authors.initials: JR
authors.lastname: Yu
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006801:Humans; D007108:Immune Tolerance / Q000276:immunology; D060889:Inducible T-Cell Co-Stimulator Protein / Q000276:immunology*; D016898:Interferon-alpha / Q000276:immunology; D016753:Interleukin-10 / Q000276:immunology; D008297:Male; D008875:Middle Aged; D013274:Stomach Neoplasms / Q000276:immunology* / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D059016:Tumor Microenvironment / Q000276:immunology*
chemical_list: C556692:ICOS protein, human; D060889:Inducible T-Cell Co-Stimulator Protein; D016898:Interferon-alpha; D016753:Interleukin-10
keywords: Dendritic cells; immune defense suppression; regulatory T cells; stomach neoplasms; tumor escape