title: Induced interleukin-19 contributes to cell-mediated immunosuppression in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.
abstract: BACKGROUND
  Coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) promotes immunosuppression, which predisposes patients to infectious complications. We investigated the role of interleukin (IL)-19 in the functions of CD4+ T cells in patients undergoing CABG with CPB.
  
  
  METHODS
  Blood samples were withdrawn from 42 patients undergoing elective CABG with CPB. Serum levels of IL-19 were analyzed by enzyme-linked immunosorbent assay (ELISA). The CD4+/CD25+ T-cell population was determined with flow cytometry. Isolated CD4+ T cells were cultured and assayed for proliferation and cytokine production under phorbol myristate acetate/ionomycin stimulation. Cytokine production and Foxp3 mRNA expression in CD4+ T cells from healthy volunteers with or without IL-19 treatment were determined with ELISA and real-time polymerase chain reaction, respectively.
  
  
  RESULTS
  Proliferation percentages were 162%, 48%, 34%, and 39%, and interferon (IFN)-γ production was 1.22 ng/mL, 0.56 ng/mL, 0.33 ng/mL, and 0.35 ng/mL in the CD4+ T cells of patients before CPB and at 24 hours, 48 hours, and 96 hours, respectively, after CPB. Serum levels of IL-19 were higher but negatively correlated with CD4+ T-cell proliferation and IFN-γ production. The populations of CD4+/CD25+ T cells and expression of Foxp3 mRNA in T cells were higher and were positively correlated with IL-19 levels after CPB. Treatment with IL-19 reduced T-cell proliferation and IFN-γ production, increased Foxp3 mRNA expression, and induced the regulatory activity of CD4+ T cells.
  
  
  CONCLUSIONS
  Interleukin-19 reduces T-cell responses and promotes the regulatory activity of CD4+ T cells. Induced IL-19 in patients undergoing CABG with CPB contributes to cell-mediated immunosuppression.
authors.affiliation: Institute of Medical Science, College of Health Science, Chang Jung Christian University, Tainan, Taiwan.
authors.forename: Ching-Hua
authors.initials: CH
authors.lastname: Yeh
authors.forename: Bor-Chih
authors.initials: BC
authors.lastname: Cheng
authors.forename: Chuan-Chih
authors.initials: CC
authors.lastname: Hsu
authors.forename: Hung-Wei
authors.initials: HW
authors.lastname: Chen
authors.forename: Jhi-Joung
authors.initials: JJ
authors.lastname: Wang
authors.forename: Ming-Shi
authors.initials: MS
authors.lastname: Chang
authors.forename: Chung-Hsi
authors.initials: CH
authors.lastname: Hsing
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D002315:Cardiopulmonary Bypass; D049109:Cell Proliferation; D002478:Cells, Cultured; D001026:Coronary Artery Bypass / Q000379:methods*; D003324:Coronary Artery Disease / Q000097:blood / Q000276:immunology / Q000601:surgery*; D017558:Elective Surgical Procedures; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D051858:Forkhead Transcription Factors / Q000096:biosynthesis / Q000235:genetics; D005786:Gene Expression Regulation; D006801:Humans; D007108:Immune Tolerance / Q000502:physiology*; D007111:Immunity, Cellular / Q000276:immunology*; D007371:Interferon-gamma / Q000096:biosynthesis; D007378:Interleukins / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D012189:Retrospective Studies
chemical_list: C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C421250:IL19 protein, human; D007378:Interleukins; D012333:RNA, Messenger; D007371:Interferon-gamma