Increased interleukin-23 receptor (IL-23R) expression is associated with disease severity in acute-on-chronic liver failure.

Background: Th17 cells mediated immune response is important in chronic hepatitis B (CHB) infection and inflammation associated diseases; however, little is known about their immunopathogenic role in acute-on-chronic liver failure (ACLF). Interleukin-23 receptor (IL-23R) is essential for the generation of pathogenic Th17 cells; therefore, we aimed to evaluate IL-23R expression and its correlation with disease severity in ACLF.

Methods: Forty-two patients with ACLF (HBV and alcohol-related), thirty-two with CHB and twenty healthy controls (HC) were studied. Circulating and intrahepatic profile of Th17 cells and IL-23R was investigated. Association of IL-23R with disease severity was determined.

Results: Circulating Th17 cells were significantly increased in both ACLF groups (P = 0.03, P = 0.006) than CHB and HC. Percentage of Th17 cells was higher in liver than peripheral blood of ACLF patients (P = 0.04). Expression of IL-23R was immensely up-regulated on Th17 cells of ACLF patients. Importantly, IL-23R not only correlated with the increased percentage of Th17 cells but also had significant association with inflammation (P = 0.03) and clinical disease severity indices including Child-Turcotte-Pugh (P = 0.001) and Model for End-Stage Liver Disease (P = 0.002) scores. The ACLF non-survivors showed higher IL-23R expression (P = 0.01). Transcription factor retinoic acid receptor-related orphan nuclear receptor gamma-t (ROR-γt) was also high in circulation and in liver of ACLF patients and it positively correlated with ALT levels (P = 0.03). Surface receptors, including CCR6, IL-17R and pro-inflammatory cytokines IL-17A, IL-22, CXCL8 and GM-CSF were highly augmented in ACLF.

Conclusion: ACLF patients express high IL-23R on Th17 cells which induces inflammation and strongly correlates with liver disease severity.