Interferon lambda 4 genotype and pathway in alcoholic hepatitis

Area of Science:

• Hepatology
• Immunology
• Genetics

Background:

• Single nucleotide polymorphisms (SNPs) in the interferon lambda 4 (IFNλ4) gene are known to affect liver inflammation and fibrosis in chronic liver disease.
• The role of these genetic variants in acute liver conditions, specifically alcoholic hepatitis, remains less understood.

Purpose of the Study:

• To investigate the association between IFNL4 gene variants and the clinical course of acute alcoholic hepatitis.
• To characterize the activation state of the interferon lambda (IFNλ) system in patients with alcoholic hepatitis.

Main Methods:

• A pilot study genotyped 58 alcoholic hepatitis patients for the rs368234815 IFNL4 SNP (IFNλ4 positive vs. negative).
• Genotypes were correlated with mortality, infection, and inflammation markers.
• Expression of the IFNL receptor 1 and IFN-inducible genes was measured in liver and peripheral leukocytes.

Main Results:

• Patients negative for IFNλ4 expression demonstrated a trend towards improved short-term survival compared to IFNλ4 positive patients (p=0.058).
• IFNλ4 negative patients had lower circulating monocyte counts and reduced plasma soluble CD163.
• Alcoholic hepatitis patients exhibited reduced IFNL receptor 1 expression in liver and blood compared to controls.
• Expression of IFN-stimulated genes was lower in patients' blood than in controls, most significantly in non-survivors.

Conclusions:

• The IFNλ4 pathway appears to be implicated in the acute disease processes of alcoholic hepatitis.
• Patients lacking IFNλ4 expression may experience a short-term survival advantage in alcoholic hepatitis.