title: [Expression of microRNA-155 and regulative T cell in sepsis patients and their relationship].
abstract: OBJECTIVE
  To investigate the adjustment effect of microRNA-155 on CD4(+)CD25(+) regulative T cell (Treg) in peripheral blood of sepsis patients, and to elucidate the role of miR-155 in the pathogenesis of sepsis.
  
  
  METHODS
  A retrospective study was conducted. 60 sepsis patients (mild n=20, moderate n=20, and severe n=20) from emergency room or intensive care unit (ICU) of the Fourth Hospital of Jiangsu University were enrolled. 20 healthy volunteers were enrolled as controls. Real-time fluorescent quantitation polymerase chain reaction (qRT-PCR) was used to detect the levels of miR-155 and Foxp3 mRNA expressions in peripheral blood. CD4(+)CD25(+) Treg cells in peripheral blood were identified by flow cytometry. Peripheral interleukin-10 (IL-10) was measured by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  The expressions of miR-155, Treg, Foxp3 mRNA and the level of IL-10 were higher in the patients with sepsis than those in healthy control group [Treg: (2.89±1.13)% vs. (2.32±0.91)%, t=10.540, P=0.002; miR-155: 1.19±0.48 vs. 0.80±0.33, t=8.605, P=0.006; Foxp3 mRNA: 0.18±0.08 vs. 0.13±0.03, t=6.862, P=0.008; IL-10: 56.89±17.28 ng/L vs. 33.24±11.93 ng/L, t=12.742, P=0.001]. These variables were elevated gradually with the elevation of acute physiology and chronic health evaluation II (APACHEII) score. The expressions of Treg, miR-155, Foxp3 mRNA and the level of IL-10 were (3.05±1.21)%, 1.36±0.79, 0.21±0.10, (62.82±21.38) ng/L in severe sepsis group; they were (2.86±0.88)%, 1.25±0.56, 0.17±0.08, (56.38±19.65) ng/L in moderate group; they were (2.61±0.87)%, 0.94±0.52, 0.15±0.05, (45.43±14.40) ng/L in mild group. The values showed significant statistical difference among the mild, moderate and severe sepsis groups (all P<0.01). Above values were significantly higher in non-survival group than those in survival group [Treg: (3.46±1.53)% vs. (2.85±1.03)%, t=14.250, P=0.005; miR-155: 1.41±0.85 vs. 1.16±0.76, t=11.875, P=0.006; Foxp3 mRNA: 0.24±0.11 vs. 0.17±0.09, t=8.795,P=0.001; IL-10: 65.47±23.58 ng/L vs. 51.70±16.86 ng/L, t=16.313, P=0.001]. The expression of miR-155 was positively correlated with the expression of CD4(+)CD25(+) Treg and Foxp3 mRNA (r 1=0.635, P 1=0.007; r 2=0.671, P 2=0.005).
  
  
  CONCLUSIONS
  The result of this study suggest that miR-155 is involved in the cell proliferation regulation of CD4(+)CD25(+) Treg cells, and play some role in the immunological dissonance in sepsis.
authors.affiliation: Department of Intensive Care Unit, the Fourth Hospital of Jiangsu University, Zhenjiang 212001, Jiangsu, China. Corresponding author: Zhao Chunhui, Email: jyk252@sina.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Chunhui
authors.initials: C
authors.lastname: Zhao
authors.forename: Qin
authors.initials: Q
authors.lastname: Cai
authors.forename: Huaying
authors.initials: H
authors.lastname: Zhu
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D049109:Cell Proliferation; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D018805:Sepsis / Q000097:blood* / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology*
chemical_list: C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508609:IL10 protein, human; C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D016753:Interleukin-10