Cytokine/chemokine patterns connect host and viral characteristics with clinics during chronic hepatitis C

Abstract Background In chronic hepatitis C virus (HCV) infection, liver tissue pathology and HCV genotype are important determinants of clinical and/or treatment-related outcome. Although consistent epidemiological and/or molecular-biological clues derived from different studies on single virus-host interactions are meanwhile published, the in vivo transcriptional responses and cellular pathways affected in >1 key aspects of the disease or treatment process are far from being understood. Methods Microarray analysis was performed in peripheral whole blood (PB) samples from 36 therapy-naïve HCV-infected patients with known liver histology. Linear regression analysis identified gene expression profiles significantly correlating (P vs. Gt. 2/3), stage of hepatic fibrosis [St. 0/1 vs. St. 2/3/4] and grade of hepatic inflammation (Gr. 0/1 vs. Gr. 2/3/4). Correlation values across all seven contrasts were considered for hierarchical clustering (HCL). Results A total of 1,697 genes showed ≥1 significant correlation results and genes involved in cell differentiation (183), immune response (53), and apoptosis (170) were leading fractions. HCL grouped the genes into six major clusters. Functional annotation analysis using DAVID (http://david.abcc.ncifcrf.gov) revealed that expression profiles that best linked these variables were highly enriched in cytokine/chemokine activity (Fisher-exact P Conclusion We identified molecular targets of the innate and adaptive immune system and validated their transcriptional specificity in vivo suggesting significant involvement in two unique outcomes during HCV treatment.