An analysis on the relationship between susceptibility to cirrhosis and polymorphisms at C-1350T and G-944C sites of CIITA gene promoter IV in chronic HBV carriers / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the susceptibility to cirrhosis and the single nucleotide polymorphisms (SNPs) at C-1350T and G-944C loci of class II transactivator (CIITA) gene promoter IV in chronic HBV carriers.</p><p><b>METHODS</b>C-1350T and G-944C loci of CIITA gene promoter IV were analyzed by sequence-specific primer PCR (PCR-SSP) in 544 chronic HBV carriers and 125 non-HBV infected healthy blood donors.</p><p><b>RESULTS</b>Among the chronic viral hepatitis B patients, there were significantly decreased frequencies of CC and TG haplotypes, and significantly increased frequency of CG haplotype among patients with liver cirrhosis (CG vs. CC: chi2=8.274, df=1, P < 0.01; CG vs. TG: chi2 = 15.027, df =1, P <0.01). There were no significant differences in the frequencies of CC and TG haplotypes between chronic hepatitis B and liver cirrhosis patients (chi2 = 1.231, df =1, P < 0.05). There were significantly increased frequencies of CC/CC (Group 1) genotype and genotypes contained CG haplotype (Group 3), and significantly decreased frequencies chi2= 7.176, df = 1, P < 0.01; Group1 vs Group 4, chi2 = 19.818, df = 1, P < 0.01; Group 3 vs Group 2, chi2 = 11.423, df = 1, P < 0.01; Group 3 vs Group 4, chi2 = 34.226, df = 1, P < 0.01; Group 1 vs Group 3, chi2 = 0.009, df = 1; Group 2 vs Group 4, chi2 = 2.176, df = 1).</p><p><b>CONCLUSION</b>Polymorphisms at -1350 and -944 loci of CIITA gene promoter IV are associated with susceptibility to liver cirrhosis in chronic HBV carriers. The chronic HBV carriers bearing CC/CC genotype or genotypes containing CG haplotype progress into liver cirrhosis with more probability.</p>

Construction of eukaryotic expression vectors containing different haplotype cDNA of human CIITA gene / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To construct eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene.</p><p><b>METHOD</b>cDNA fragments of three different CIITA haplotypes were obtained by inducing one or two single nucleotide mutations of wild type recombinant plasmid EBS-NPL-CIITA cDNA, which correspond to two non-homonymy single nucleotide polymorphism (SNP) sites in the coding region of human CIITA gene, using overlap extension PCR site-directed mutagenesis technology. The above-mentioned three haplotype cDNAs were respectively cloned to EBS-NPL-CIITA linearized vectors. Positive clones were identified by colonial PCR and restriction endonuclease digestion and were sent to be sequenced. Then eukaryotic expression vectors containing four different haplotypes and an empty vector EBS-NPL were transfected into HepG2 cells respectively. HLA-DR was detected by indirect cell immunofluorescence technique.</p><p><b>RESULTS</b>The cDNA fragments of three different human CIITA haplotypes were successfully constructed, and the eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene were obtained. No expression of HLA-DR was observed in the original HepG2 cells and empty vector transfected HepG2 cells and the expression of HLA-DR emerged in the HepG2 cells transfected with four eukaryotic expression vectors.</p><p><b>CONCLUSION</b>The eukaryotic expression vectors containing three different haplotype cDNAs of human CIITA gene were successfully constructed, and they are essential for our further study of the functional differences of them.</p>