title: Expression of programmed cell death-1 and its ligand B7 homolog 1 in peripheral blood lymphocytes from patients with peripartum cardiomyopathy.
abstract: BACKGROUND
  Immune response has been postulated to play a prominent role in the pathogenesis of peripartum cardiomyopathy (PPCM). Given the importance of programmed death (PD)-1 and its ligand B7 homologue 1 (B7-H1) costimulatory molecules as an immune regulatory pathway, this study aimed to investigate the effect of PD-1 and B7-H1 expression on immune response in peripheral blood lymphocytes from the patients with PPCM.
  
  
  OBJECTIVE
  PD-1 and B7-H1 may be involved in modulating immune response in PPCM.
  
  
  METHODS
  Peripheral blood lymphocytes were obtained from PPCM and pregnancy-matched healthy women. PD-1 and B7-H1 expression were determined using fluorescence quantitative reverse transcription-polymerase chain reactions (RT-PCR) and Western blot. The presence of serum interferon (IFN)-γ and interleukin (IL)-4 were determined with enzyme-linked immunosorbent assay.
  
  
  RESULTS
  The levels of pro-brain natriuretic peptide and IFN-γ were markedly elevated, whereas the levels of left ventricular ejection fraction and IL-4 were significantly reduced in PPCM patients compared to controls. Additionally, both RT-PCR and Western blot revealed that the levels of PD-1 and B7-H1 expression were decreased significantly in PPCM patients compared with controls. A significant positive correlation was observed between PD-1 and B7-H1 expression. Furthermore, PD-1 and B7-H1 expression showed significant negative correlation with IFN-γ, as well as positive correlation with IL-4. Therefore, decreased expression of PD-1 and B7-H1 led to a dysregulating immune response such that cellular immunity linked to T helper (Th)1 cells was predominant over humoral immunity linked to Th2 cells in PPCM.
  
  
  CONCLUSIONS
  This study provided the first findings that PD-1 and B7-H1 expression were decreased, which might impair functional regulation of negative costimulation on immune response that may work in the etiopathogenesis of PPCM.
authors.affiliation: Department of Cardiovascular Medicine, First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an, China.
authors.forename: Guozhi
authors.initials: G
authors.lastname: Xia
authors.affiliation: Department of Cardiovascular Medicine, First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an, China.
authors.forename: Xiaopu
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Cardiovascular Medicine, First Affiliated Hospital, Medical College, Xi'an Jiaotong University, Xi'an, China.
authors.forename: Xinye
authors.initials: X
authors.lastname: Yao
authors.affiliation: Department of Cardiovascular Medicine, Shaanxi Provincial People's Hospital, Xi'an, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Yao
authors.affiliation: Department of Cardiovascular Medicine, Shaanxi Provincial People's Hospital, Xi'an, China.
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Cardiovascular Medicine, Shaanxi Provincial People's Hospital, Xi'an, China.
authors.forename: Junkui
authors.initials: J
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D060890:B7-H1 Antigen / Q000097:blood* / Q000235:genetics / Q000276:immunology; D009202:Cardiomyopathies / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007371:Interferon-gamma / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D020097:Natriuretic Peptide, Brain / Q000097:blood; D058725:Peripartum Period / Q000097:blood*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood* / Q000175:diagnosis / Q000276:immunology; D061026:Programmed Cell Death 1 Receptor / Q000097:blood* / Q000235:genetics / Q000276:immunology; D018417:Th1 Cells / Q000737:chemistry* / Q000276:immunology; D018418:Th2 Cells / Q000737:chemistry / Q000276:immunology; D055815:Young Adult
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; C573415:IFNG protein, human; C508598:IL4 protein, human; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor; D020097:Natriuretic Peptide, Brain; D015847:Interleukin-4; D007371:Interferon-gamma
keywords: B7-H1; Cardiomyopathy; Costimulation; Immune; PD-1; Peripartum