The transforming growth factor 1/interleukin-31 (TGF-1/IL-31) pathway plays an important role in the process of cell injury and inflammation. The purpose of this work was to explore the role of the TGF-1/IL-31 pathway in the cytopathic process of hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). The quantitative serum levels of TGF-1, IL-9, IL-10, IL-17, IL-22, IL-23, IL-31, IL-33, and IL-35 were analyzed among chronic hepatitis B (CHB) patients (n ؍ 17), ACLF patients (n ؍ 18), and normal control (NC) subjects (n ؍ 18). Disease severity in patients with ACLF was assessed using the model for endstage liver disease (MELD) and Child-Pugh scores. Serum TGF-1 levels were strongly positively correlated with IL-31 in all subjects, and both of them were positively correlated with IL-17, IL-22, and IL-33. In CHB and ACLF patients, serum levels of TGF-1 and IL-31 were both increased significantly compared with those in NC subjects and positively correlated with total bilirubin (TBil) and alpha-fetoprotein (AFP) levels. ACLF patients showed the highest levels of TGF-1 and IL-31, which were positively correlated with Child-Pugh scores. Furthermore, the recovery from the liver injury in CHB was accompanied by decreased TGF-1 and IL-31 levels. More importantly, serum levels of TGF-1 and IL-31 were markedly upregulated in ACLF nonsurvivors, and IL-31 displayed the highest sensitivity and specificity (85.7% and 100.0%, respectively) in predicting nonsurvival of ACLF patients. Increasing activity of the TGF-1/IL-31 pathway is well correlated with the extent of liver injury, disease severity, and nonsurvival of ACLF patients, while reducing activity is detected along the recovery from liver injury in CHB, suggesting its potential role in the pathogenesis of liver injury during chronic HBV infection.
Hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) is triggered mainly by severe extensive liver injury, and the exact mechanisms of massive destruction of HBV-infected hepatocytes remain unclear. However, one of the current assumptions is that the imbalance of the cytokine network, the so-called cytokine storm theory (1), points to potential involvement of inflammatory cytokines in destroying the HBV-infected cells, which may provide an explanation for the aggravation of liver injury.Transforming growth factor-1 (TGF-1) is a 25-kDa homodimeric protein composed of two subunits linked by a disulfide bond and is a powerful inhibitor of DNA synthesis and cellular proliferation (2). It also mediates formation of extracellular matrix and facilitates cell differentiation (3). Previous studies have shown that TGF-1 plays a role in developing liver failure (LF). Miwa et al. found that the mRNA and protein expression of TGF-1 were significantly upregulated in both the plasma and liver tissue in patients with fulminant liver failure (FLF) (4). Yoshimoto et al. found that the overexpression of TGF-1 delayed liver regeneration and promoted perisinusoidal fibrosis and hepatocyte apoptos...