Functional Gene Polymorphisms of Interleukin-10 are Associated with Liver Disease Progression in Japanese Patients with Hepatitis C Virus Infection

Abstract

OBJECTIVE: The inter-individual difference in response to liver injury appears to be important in the progression of liver fibrosis. Interleukin 10 (IL-10) is an anti-inflammatory cytokine, and several functional gene polymorphisms have been found. The aim of this study was to examine the possible association of IL-10 polymorphisms with the progression of liver fibrosis in hepatitis C virus (HCV)-related chronic liver disease patients. METHODS: We examined the IL-10 -1087 A/G and -824 T/C gene polymorphisms in 184 Japanese patients with HCV-related chronic liver disease: 94 chronic hepatitis (CH) and 90 with liver cirrhosis (LC). RESULTS: There were no significant differences in the genotype distributions or allele frequencies of IL-10 -824 T/C and -1087 A/G between the CH and LC groups. However, among the cirrhotic patients, the lower transcriptional allele, -824 T homozygotes had significantly lower serum albumin and platelet counts, and a higher Child-Pugh score than the -824 C carriers, and the lower transcriptional allele, -1087 A homozygotes had a higher ICG-R 15 compared with -1087 G carriers. Haplotype analysis of IL-10 -1087/-824 showed no significant difference between the CH and LC groups, but the combinations of AT and AC haplotypes (AT/AT, AT/AC and AC/AC) had a significantly higher ICG-R 15 than the GC carriers. CONCLUSION: IL-10 lower transcriptional -824 T allele, -1087 A allele, and -1087/-824 haplotypes AT and AC are risk factors for the progression of liver fibrosis in HCV-related chronic liver disease.