Autoimmune hepatitis association with single nucleotide polymorphism of interleukin-2, but not interferon-gamma

Clin Res Hepatol Gastroenterol. 2018 Apr;42(2):134-138. doi: 10.1016/j.clinre.2017.06.005. Epub 2017 Dec 26.

Abstract

Background: Autoimmune hepatitis (AIH) is a chronic inflammation in hepatocellular tissues associated with circulating autoantibodies. Imbalance in T-cells population and dysregulation in several cytokine profiles has been implicated in pathogenesis of AIH. This study was performed to assess potential association of AIH with interleukin-2 (IL-2) and interferon-gamma (IFN-γ) genes single nucleotide polymorphisms (SNPs).

Methods: Fifty-six patients with AIH and 139 healthy individuals were enrolled in this study. IL-2 and IFN-γ typing was performed, using polymerase chain reaction with sequence-specific primers (PCR-SSP) assay. The frequencies of alleles, genotypes and haplotypes in AIH patients were compared to healthy controls.

Results: IL-2 T allele at position +166 (rs2069763) showed significant higher frequency in AIH group (36%), compared to the controls (21%) (OR=2.06; 95% CI, 1.24-3.43, P-value<0.01). The frequency of IL-2 TT genotype at +166 position was also associated with AIH (OR=18.68, 95% CI 3.74-126.04, P-value<0.01). G/T alleles of IL-2 at -330 (rs2069762) and A/T alleles on UTR +5644 position at IFN-γ and their subsequent haplotypes, did not show significant association with AIH.

Conclusions: This study identified IL-2T allele at +166 position and TT genotype as susceptibility gene in AIH which would provide better understandings into the mechanisms of AIH and potential immune modulation therapies.

Keywords: Autoimmune hepatitis; Cytokine; Interferon-gamma; Interleukin-2; Single nucleotide polymorphism.

MeSH terms

  • Child
  • Hepatitis, Autoimmune / genetics*
  • Humans
  • Interferon-gamma / genetics*
  • Interleukin-2 / genetics*
  • Polymorphism, Single Nucleotide*

Substances

  • Interleukin-2
  • Interferon-gamma