title: The role of Fas expression on the occurrence of immunosuppression in severe acute pancreatitis.
abstract: BACKGROUND
  Severe acute pancreatitis (SAP) is a dangerous illness with high mortality where most patients do not die of excessive inflammation, but die of immunosuppression and multiple infections at a later stage. The mechanism of immunosuppression in SAP is unknown.
  
  
  OBJECTIVE
  The purpose of this study was to analyze the role of Fas expression on the occurrence of immunosuppression in patients with SAP.
  
  
  METHODS
  Forty-eight patients with pancreatitis were divided into two groups: 20 cases with SAP (7 cases with sepsis, 13 cases without sepsis) and 28 cases with mild acute pancreatitis (MAP). Twenty-eight healthy volunteers were selected as controls. Fas mRNA expression in peripheral blood was detected by qPCR and Fas protein of lymphocyte membranes; T lymphocyte subsets and expression of monocyte Human leukocyte antigen DR (HLA-DR) in peripheral blood were detected by flow cytometry.
  
  
  RESULTS
  Compared with MAP and control groups, expression level of Fas mRNA and lymphocyte Fas protein in peripheral blood were significantly increased in the SAP group (all P < 0.01). There was a further significant increase in the SAP group with sepsis compared to those without sepsis (all P < 0.01). The CD4(+) T cell ratio, CD4(+)/CD8(+) ratio and monocyte HLA-DR expression in the SAP group were decreased significantly compared with MAP and control groups (all P < 0.01). Significant negative relationships were observed between Fas mRNA expression and CD4(+) T-cell ratio, CD4(+)/CD8(+) ratio, and monocyte HLA-DR expression in SAP patients with sepsis (all P < 0.05).
  
  
  CONCLUSIONS
  The results suggest that expression level of Fas is related to severity and immune status of pancreatitis. Overexpression of Fas may lead to the occurrence of immunosuppression and sepsis.
authors.affiliation: The First Clinical Medical College of Jinan University, Guangzhou, 510630, Guangdong Province, China.
authors.forename: Yueqiu
authors.initials: Y
authors.lastname: Qin
authors.forename: Liao
authors.initials: L
authors.lastname: Pinhu
authors.forename: Yanwu
authors.initials: Y
authors.lastname: You
authors.forename: Suren
authors.initials: S
authors.lastname: Sooranna
authors.forename: Zhansong
authors.initials: Z
authors.lastname: Huang
authors.forename: Xihan
authors.initials: X
authors.lastname: Zhou
authors.forename: Yixia
authors.initials: Y
authors.lastname: Yin
authors.forename: Sien
authors.initials: S
authors.lastname: Song
mesh_terms: D000328:Adult; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D005260:Female; D005786:Gene Expression Regulation / Q000276:immunology*; D006684:HLA-DR Antigens / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D010195:Pancreatitis / Q000276:immunology* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019014:fas Receptor / Q000235:genetics / Q000378:metabolism*
chemical_list: C491901:FAS protein, human; D006684:HLA-DR Antigens; D012333:RNA, Messenger; D019014:fas Receptor