title: High level of IL-27 positively correlated with Th17 cells may indicate liver injury in patients infected with HBV.
abstract: BACKGROUND
  Interleukin-6/IL-12 family cytokines play a key role in inflammatory diseases via their effects on the differentiation or regulation of T helper cells.
  
  
  OBJECTIVE
  The aim of this study was to determine the role of interleukin-27 (IL-27) and its association with helper T cells in hepatitis B virus (HBV)-infected patients.
  
  
  METHODS
  Samples were assessed from 51 HBV-infected patients [28 chronic hepatitis B (CHB) subjects and 23 acute-on-chronic liver failure (ACLF) subjects] and 18 normal controls (NC). Serum IL-27 levels were examined by enzyme-linked immunosorbent assay. Circulating helper T cells were determined using flow cytometry and associations between IL-27 expression and helper T cells were analysed.
  
  
  RESULTS
  Serum IL-27 levels rose in HBV-infected patients (502.88 ± 23.35 pg/ml) compared to (NC, 277.14 ± 23.96 pg/ml, P < 0.0001). Furthermore, it significantly increased in patients with ACLF (587.90 ± 33.08 pg/ml) when compared with CHB (433.04 ± 26.57 pg/ml, P = 0.001). However, no statistically significant differences were observed between IL-27 and the presence of HBeAg. High levels of IL-27 then positively correlated with Tbil levels (r = 0.401, P = 0.004), but negatively associated with prothrombin time activity levels (r = -0.496, P < 0.001), and a slightly negative correlation trend with HBV-DNA loads (r = -0.228, P = 0.107) existed in these HBV-infected subjects. Additionally, frequency of circulating interleukin-17-producing CD4(+) T cells (Th17 cells) increased in HBV-infected patients (ACLF, mean, 5.39%; CHB, median, 3.12%) as compared to NC subjects (median, 2.22%, P < 0.0001). Moreover, correlation analysis showed that serum IL-27 level was positively associated with circulating Th17 cells (r = 0.342, P = 0.036).
  
  
  CONCLUSIONS
  These results provided evidence that IL-27 was positively correlated with Th17 cells commitment, and may exerted a proinflammatory effect in the development of liver injury in HBV-infected patients.
authors.affiliation: Department of Infectious Diseases, The Third Affiliated Hospital of Sun-Yat-Sen University, GuangZhou, China; Key Laboratory of Tropical Disease Control (Sun Yat-Sen University), Ministry of Education, Guangzhou, China.
authors.forename: Geng-Lin
authors.initials: GL
authors.lastname: Zhang
authors.forename: Dong-Ying
authors.initials: DY
authors.lastname: Xie
authors.forename: Yi-Nong
authors.initials: YN
authors.lastname: Ye
authors.forename: Chao-Shuang
authors.initials: CS
authors.lastname: Lin
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Zhang
authors.forename: Yu-Bao
authors.initials: YB
authors.lastname: Zheng
authors.forename: Zhan-Lian
authors.initials: ZL
authors.lastname: Huang
authors.forename: Liang
authors.initials: L
authors.lastname: Peng
authors.forename: Zhi-Liang
authors.initials: ZL
authors.lastname: Gao
mesh_terms: D015415:Biomarkers / Q000097:blood*; D002681:China; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D019694:Hepatitis B, Chronic / Q000097:blood / Q000150:complications / Q000276:immunology*; D006801:Humans; D064094:Interleukin-27 / Q000097:blood*; D017114:Liver Failure, Acute / Q000097:blood / Q000209:etiology / Q000276:immunology*; D010865:Pilot Projects; D011517:Prothrombin Time; D058504:Th17 Cells / Q000276:immunology*
chemical_list: D015415:Biomarkers; D064094:Interleukin-27
keywords: IL-27; Th17 cells; hepatitis B virus; immunopathogenesis