Hepatic Expression of CXC Chemokines Predicts Portal Hypertension and Survival in Patients With Alcoholic Hepatitis

Background & Aims

Alcoholic hepatitis (AH) is characterized by hepatocellular damage, inflammation, and fibrosis. We performed a prospective study to associate hepatic expression of the CXC subfamily of chemokines with histology findings and prognosis of patients with AH.

Methods

Liver biopsy samples from 105 patients with AH and 5 normal liver samples (controls) were evaluated for steatosis, inflammation, fibrosis, and cholestasis. Computer-based morphometric analysis assessed the numbers of infiltrating CD3⁺ T cells and CD15⁺ cells (neutrophils); terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling staining was used to quantify apoptosis. Expression of CXC and CC chemokines and selected signaling components were assessed by quantitative reverse-transcription polymerase chain reaction; protein levels of interleukin (IL)-8 and Gro-α also were determined by immunohistochemistry. Serum levels of IL-8 and Gro-α were measured by enzyme-linked immunosorbent assay. The Cox regression model identified variables associated with mortality.

Results

Most patients (75%) had severe AH; their 90-day mortality rate was 21.9%. In AH liver samples, expression of the CXC subfamily members IL-8, Gro-α, CXCL5, CXCL6, CXCL10, and platelet factor 4 was up-regulated and compared with controls. The CC chemokine CCL2, but not CCL5, also was up-regulated. Higher expression levels of IL- 8, CXCL5, Gro-γ, and CXCL6 were associated with worse prognosis. Expression of CXC components correlated with neutrophil infiltration and the severity of portal hypertension. In the multivariate analysis, IL-8 protein levels were an independent predictor of 90-day mortality. IL-8 and Gro-α serum levels did not correlate with prognosis.

Conclusions

Hepatic expression of CXC components correlates with prognosis of patients with AH. Reagents that target CXC chemokines might be developed as therapeutics.

Abbreviations used in this paper: ALD, alcohol-induced liver disease, AH, alcoholic hepatitis, HR, hazard ratio, HVPG, hepatic venous pressure gradient, IL, interleukin, CXCR, chemokine receptor, PF4, platelet factor 4, ENA-78, epithelial-derived neutrophil-activating peptide 78, GCP-2, granulocyte chemotactic protein 2, γIP-10, interferon-γ–induced protein 10, IFN, interferon, MCP-1, monocyte chemoattractant protein 1, STAT-1, signal transducer and activator of transcription factor 1, RANTES, regulated upon activation, normally T-expressed, and presumably secreted