Abstract:

Objective To investigate the correlation between the level of serum interleukin 33（IL-33）and its gene polymorphism and the clinical outcome of hepatitis B virus（HBV） infection. Methods Totally,341 patients with HBV infection were enrolled,including 93 patients with self limited HBV infection（self limited infection group）,91 asymptomatic chronic HBV carriers（HBV carrying group）,90 patients with chronic hepatitis B（CHB）（CHB group） and 67 patients with hepatitis B related cirrhosis（liver cirrhosis group）. The single nucleotide polymorphisms of alanine aminotransferase（ALT）,aspartate aminotransferase（AST）,total bilirubin（TB）,IL-33,IL-33 gene rs10975519 and HBV DNA load were determined. Pearson correlation analysis was used to evaluate the correlation between IL-33 and ALT,AST and TB. Results The levels of ALT,AST,TB and IL-33 increased successively in self limited infection group,HBV carrying group,CHB group and liver cirrhosis group（P<0.05）. Pearson correlation analysis showed that the level of IL-33 was positively correlated with the levels of ALT,AST and TB（r values were 0.447,0.459 and 0.512,P<0.001,<0.001 and 0.018,respectively）. According to the upper limit of the reference interval of each index,CHB group and liver cirrhosis group were classified,and the levels of serum IL-33 were compared. In CHB group,the level of serum IL-33 in patients of HBV DNA>1×10⁵ was higher than that in patients of HBV DNA≤1×10⁵（P<0.05）. There was no statistical significance in serum IL-33 levels among ALT>40 and ≤40 U/L,AST>40 and ≤40 U/L,TB>20 and ≤20 μmol/L groups（P>0.05）. In liver cirrhosis group,the level of serum IL-33 in HBV DNA load>1×10⁵,ALT>40 U/L,AST>40 U/L and TB >20 μmol/L patients was higher than that of HBV DNA load≤1×10⁵,ALT≤40 U/L,AST≤40 U/L and TB≤20 μmol/L patients（P<0.05）. There was statistical significance in genotype and allele distribution frequency of rs10975519 of IL-33 gene in each group（P<0.05）. The distribution frequency of TT genotype was the highest in self limited infection group,and it was the lowest in liver cirrhosis group. The distribution frequencies of TC and CC genotypes were the lowest in self limited infection group,and they were the highest in liver cirrhosis group. Conclusions The level of IL-33 is related to the clinical outcome of HBV infection. The C allele at rs10975519 of IL-33 gene may increase the risk of CHB progression to liver cirrhosis.

Key words: Interleukin 33, Gene polymorphism, Hepatitis B virus, Chronic hepatitis B, Liver cirrhosis