IRG1 increases MHC class I level in macrophages through STAT-TAP1 axis depending on NADPH oxidase mediated reactive oxygen species.

The major histocompatibility complex (MHC) is the connection between innate immunity and acquired immune system. Recently, many studies reported that the immunoresponsive gene 1 (IRG1) play an important role on innate immunity including reactive oxygen species (ROS), antiviral effect and expression of inflammatory factors. However, the function of IRG1 in antigen presenting remains unclear. In this study, we found that overexpressed-IRG1 promoted MHC I level instead of MHC II in macrophages membrane. Besides, IRG1 increased expression of some transporter proteins associated with antigen processing involving TAP1, PSMB9 depending on ROS. By detecting the activation of glucose-6-phosphate dehydrogenase (G6PD), we confirmed that IRG1 could increase ROS level by promoting pentose phosphate pathway (PPP). DPI, an inhibitor of NADPH oxidase (NOX), also significant attenuated TAP1 and MHC I level in IRG1-overexpressed macrophages. Finally, results showed that phosphorylation of STAT1/3 involved in IRG1-mediated TAP1 and MHC I expression. In conclusion, IRG1 increased MHC class I level in macrophages through STAT1/3-TAP1 axis depending on PPP and NOX mediated ROS.

Polymorphisms in IRG1 gene associated with immune responses to hepatitis B vaccination in a Chinese Han population and function to restrain the HBV life cycle.

Vaccination against the hepatitis B virus (HBV) is extensively used as an effective method to prevent HBV infection. However, nearly 10% of healthy adults fail to produce a protective level of antibodies against the hepatitis B vaccine, and multiple genetic variants are known to affect the immune response to the hepatitis B vaccine. The aim of the present study was to investigate the association between polymorphisms in immunoresponsive gene 1 (IRG1) gene and the immune response to hepatitis B vaccination in a Chinese Han population. Four single nucleotide polymorphisms (SNPs) located in the IRG1 gene were genotyped in 1230 high-responders and 451 non-responders to hepatitis B vaccination. The SNPs rs17470171 and rs17385627 were associated with the immune response to hepatitis B vaccination (P = 0.014 and 0.029, respectively). In addition, the haplotypes G-A-A-A (rs614171-rs17470171-rs9530614-rs17385627, P = 0.0042, OR = 0.68) and A-A (rs17470171-rs17385627, P = 0.0065, OR = 0.72) exerted a protective role in the immune response to hepatitis B vaccination. Allele 'A' of rs17470171 and allele 'A' of rs17385627 show higher levels of expression for the IRG1 gene compared with allele 'C' of rs17470171 and allele 'T' of rs17385627 as demonstrated by luciferase reporter and overexpression assays. In addition, we observed that IRG1 inhibited the HBV life cycle and that IRG1 rs17385627 allele 'A' was more effective than rs17385627 allele 'T' at eliminating HBV in HepG2.2.15 cells. These findings suggest that polymorphisms in the IRG1 gene are associated with the immune response to hepatitis B vaccination. The antiviral effect of IRG1 was confirmed using HBV infection cell models.

Positive Association Between Type 2 Diabetes Risk Alleles Near CDKAL1 and Reduced Birthweight in Chinese Han Individuals.

BACKGROUND: Fetal insulin hypothesis was proposed that the association between low birth weight and type 2 diabetes is principally genetically mediated. The aim of this study was to investigate whether common variants in genes CDKAL1, HHEX, ADCY5, SRR, PTPRD that predisposed to type 2 diabetes were also associated with reduced birthweight in Chinese Han population. METHODS: Twelve single nucleotide polymorphisms (rs7756992/rs10946398 in CDKAL1, rs1111875 in HHEX, rs391300 in SRR, rs17584499 in PTPRD, rs1170806/rs9883204/rs4678017/rs9881942/rs7641344/rs6777397/rs6226243 in ADCY5) were genotyped in 1174 unrelated individuals born in Peking Union Medical College Hospital from 1921 to 1954 by TaqMan allelic discrimination assays, of which 645 had normal glucose tolerance, 181 had developed type 2 diabetes and 348 impaired glucose regulation. Associations of these 12 genetic variants with birthweight and glucose metabolism in later life were analyzed. RESULTS: Birthweight was inversely associated with CDKAL1-rs10946398 (ß = -41 g [95% confidence interval [CI]: -80, -3], P = 0.034), common variants both associated with increased risk of impaired glucose metabolism and decreased insulin secretion index later in life. After adjusting for sex, gestational weeks, parity and maternal age, the risk allele of CDKAL1-rs7756992 was associated with reduced birthweight (ß = -36 g [95% CI: -72, -0.2], P = 0.048). The risk allele in SRR showed a trend toward a reduction of birthweight (P = 0.085). CONCLUSIONS: This study identified the association between type 2 diabetes risk variants in CDKAL1 and birthweight in Chinese Han individuals, and the carrier of risk allele within SRR had the trend of reduced birthweight. This demonstrates that there is a clear overlap between the genetics of type 2 diabetes and fetal growth, which proposes that lower birth weight and type 2 diabetes may be two phenotypes of one genotype.

CD3Z genetic polymorphism in immune response to hepatitis B vaccination in two independent Chinese populations.

Vaccination against hepatitis B virus is an effective and routine practice that can prevent infection. However, vaccine-induced immunity to hepatitis B varies among individuals. CD4(+) T helper cells, which play an important role in both cellular and humoral immunity, are involved in the immune response elicited by vaccination. Polymorphisms in the genes involved in stimulating the activation and proliferation of CD4(+) T helper cells may influence the immune response to hepatitis B vaccination. In the first stage of the present study, a total of 111 single nucleotide polymorphisms (SNPs) in 17 genes were analyzed, using the iPLEX MassARRAY system, among 214 high responders and 107 low responders to hepatitis B vaccination. Three SNPs (rs12133337 and rs10918706 in CD3Z, rs10912564 in OX40L) were associated significantly with the immune response to hepatitis B vaccination (P = 0.008, 0.041, and 0.019, respectively). The three SNPs were analyzed further with the TaqMan-MGB or TaqMan-BHQ probe-based real-time polymerase chain reaction in another independent population, which included 1090 high responders and 636 low responders. The minor allele 'C' of rs12133337 continued to show an association with a lower response to hepatitis B vaccination (P = 0.033, odds radio = 1.28, 95% confidence interval = 1.01-1.61). Furthermore, in the stratified analysis for both the first and second populations, the association of the minor allele 'C' of rs12133337 with a lower response to hepatitis B vaccination was more prominent after individuals who were overweight or obese (body mass index ≥25 kg/m(2)) were excluded (1(st) stage: P = 0.003, 2(nd) stage: P = 0.002, P-combined = 9.47e-5). These findings suggest that the rs12133337 polymorphism in the CD3Z gene might affect the immune response to hepatitis B vaccination, and that a lower BMI might increase the contribution of the polymorphism to immunity to hepatitis B vaccination.

[Single nucleotide polymorphisms of promoter of human leukocyte antigen-DQB1 alleles in Chinese Han patients with Vogt-Koyanagi-Harada syndrome].

OBJECTIVE: To investigate the single nucleotide polymorphism of the promoter of HLA-DQB1(QBP) in Chinese Han patients with Vogt-Koyanagi-Harada syndrome. METHODS: Case-control design was applied. Eighty-eight Chinese Han patients with Vogt-Koyanagi-Harada syndrome and 88 non-Vogt-Koyanagi-Harada syndrome controls were admitted. DNA was extracted from the peripheral white blood cells of the subjects by the phenol-chloroform method. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and clone-sequencing were applied to determine the sequences of the promoter of HLA-DQB1. Chromans and Bioedit software were used to analyze the sequences of the promoter of HLA-DQB1. Chi-square test and Fisher exact test were applied to compare the frequencies of bands of QBPs and SNPs for the two groups. RESULTS: Sixteen band patterns of HLA-QBP were shown by polyacrylamide gel electrophoresis (PAGE). The band frequencies of QBPb (corresponding gene sequence was QBP2.1 + 77C > A, chi2 = 26.01, Pc < 0.001) and QBPl (corresponding gene sequence was QBP3.3, chi2 = 16.99, Pc < 0.001) were significantly higher in patients with Vogt-Koyanagi-Harada syndrome than that in normal controls (Pc < 0.001). However, the frequencies of QBPg (corresponding gene sequence was QBP3.1, chi2 = 12.10, Pc < 0.05) and QBPn (corresponding gene sequence was QBP6.1 + 39G > A, chi2 = 14.64, Pc < 0.05) were significantly lower in patients with Vogt-Koyanagi-Harada syndrome than those of the controls. Twelve SNPs were found in all subjects. The frequency of C allele at position -189C/A in patients with Vogt-Koyanagi-Harada syndrome was significantly higher than that in controls (chi2 = 45.92, P = 0.000). However, the frequency of G allele at position -227G/A in patients with Vogt-Koyanagi-Harada syndrome was significantly lower as compared with that in the normal controls (chi2 = 15.63, P = 0.000). CONCLUSIONS: C allele of -189C/A is a genetically susceptible factor of Vogt-Koyanagi-Harada syndrome and G allele of -227G/A is the protective factor of Vogt-Koyanagi-Harada syndrome.

[Polymorphism of HLA-DQB1 alleles in Chinese Han patients with Vogt-Koyanagi-Harada syndrome].

OBJECTIVE: To investigate the frequency of HLA-DQB1 alleles in Chinese Han patients with Vogt-Koyanagi-Harada syndrome (VKH) and to analyze the relationships among the alleles and clinical manifestations. METHODS: Eighty-eight Chinese Han patients with VKH and 88 non-VKH normal controls were admitted. DNA was extracted from white blood cells of the subjects by phenol-chloroform method. Thirteen alleles were typed by polymerase chain reaction-sequence specific primer (PCR-SSP). Relationships among alleles and clinical features were analyzed. RESULTS: Twelve of thirteen already known HLA-DQB1 alleles were typed by PCR-SSP in patients with VKH. The most frequent allele in patients with VKH was HLA-DQB1*0401 (31.8%) and this was significantly higher than that of normal controls (31.8% vs. 4.6%, chi(2) = 44.00, P = 0.000, OR = 9.8, 95% CI 4.51 - 21.31). So was for HLA-DQB1*0303 (6.8% vs. 0.6%, chi(2) = 9.67, P = 0.002, OR = 12.81, 95% CI 1.65 - 99.58). On the contrary, the frequency of HLA-DQB1*0601 (1.7% vs. 9.7%, chi(2) = 10.39, P = 0.001, OR = 0.16, 95% CI 0.05 - 0.56) and HLA-DQB1*0302 (6.3% vs. 19.3%, chi(2) = 13.48, P = 0.000, OR = 0.28, 95% CI 0.14 - 0.57) in patients with VKH were significantly lower than that of normal controls. They found no statistical differences of clinical manifestations such as age of onset, visual acuity, cataract, complicated glaucoma, exudative retinal detachment between HLA-DQB1*0401 positive group and HLA-DQB1*0401 negative group in patients with VKH. CONCLUSIONS: (1) Alleles of HLA-DQB1*0401 and HLA-DQB1*0303 are susceptible to VKH. HLA-DQB1*0601 and HLA-DQB1*0302 are resistant to VKH. This is the first report that associates HLA-DQB1*0302 with resistant of VKH. (2) PCR-SSP is a rapid method for typing the HLA-DQB1 alleles and can be used routinely.

Association of HLA-DQB1 gene polymorphisms with outcomes of HBV infection in Chinese Han population.

BACKGROUND: Host genetic factors and environmental factors including hepatitis B virus (HBV) genotype are widely studied for the different outcomes of HBV infection. Human leukocyte antigen (HLA) plays an important role in the immunological reaction to HBV infection. AIMS: To explore whether the HLA-DQB1 allele polymorphisms are associated with the outcome of HBV infection in a Chinese Han population. PATIENTS: One hundred and thirty three HBV subjects with spontaneous recovery and 151 chronic hepatitis B patients were recruited into this case-control study in the Beijing area of China. METHODS: Sequence specific primer-polymerase chain reaction (SSP-PCR) was used to detect 13 alleles of HLA-DQB1 gene and 13 alleles of HLA-DRB1 gene. Multivariate logistic regression model was performed to detect the association of candidate factors with outcome of HBV infection by SAS 9.1.2 software package. RESULTS: The frequency of HLA-DQB1*0502 allele in the chronic hepatitis B group was significantly higher than that in the group with spontaneous recovery independent of HLA-DRB1 (odds ratio 95%CI 1.8-190). In this study there was no evidence to indicate that cigarette smoking or alcohol consumption was associated with the outcome of HBV infection. CONCLUSION: HLA-DQB1*0502 is independently associated with the outcome of HBV infection and is one host genetic factor affecting HBV infection outcome. At the same time, we can not rule out the possibility that excluded genes and alleles may also affect outcome.

[Association of Taq I T/C and Fok I C/T polymorphisms of vitamin D receptor gene with outcome of hepatitis B virus infection].

OBJECTIVE: To determine whether Taq I T/C and Fok I C/T polymorphisms of vitamin D Receptor (VDR) gene was associated with the outcomes of hepatitis B virus (HBV) infection. METHODS: A total of 212 HBV self-limited infection individuals, 244 asymptomatic HBsAg carriers and 391 chronic hepatitis B (HB) patients were recruited to conduct a case-control study. VDR-Taq I T/C and VDR-Fok I C/T polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The frequency of VDR-Fok I allele C in the chronic HB patients was 45.8%, significantly higher than 38.2% of the self-limited infection individuals (chi(2) = 6.43, P = 0.01). The frequencies of VDR-Fok I genotypes TT, TC, and CC in HB patients were 30.7%, 47.1%, and 22.2% respectively, and 41.0% (TT), 41.5% (TC), and 17.5% (CC) in the self-limited infection individuals. There was a statistically significant difference between HB patients and self-limited infection individuals (chi(2) = 6.76, P = 0.03). The results of univariate analysis showed that the subjects carrying VDR-Fok I CC/TC genotype had 1.57-fold elevated risk for developing chronic HB when they were infected HBV (OR = 1.57, P = 0.01). A multiple logistic regression analysis revealed that VDR-Fok I CC/CT was independently associated with chronic HB after adjusting both potential confounding effects of gender (OR = 1.70, P = 0.021). The statistically significant association between TaqI T/C polymorphism and outcome of HBV infection was not demonstrated in the study. The frequency of haplotype TC of VDR-TaqI and Fok I in HB patients was 2.3080%, significantly higher than 0.5391% of the self-limited infection individuals (chi(2) = 6.08, P = 0.01). However, the frequency of haplotype TT in the HB patients was 1.5283%, significantly lower than 3.7061% of the self-limited infection individuals (chi(2) = 5.65, P = 0.02) and 3.4820% of the HBV carriers (chi(2) = 5.12, P = 0.02). CONCLUSION: VDR gene polymorphism is probably an influence factor on the genetic susceptibility of HBV infection.

[Study on association between vitamin D receptor gene polymorphisms and the outcomes of HBV infection].

OBJECTIVE: To explore whether the vitamin D receptor gene (VDR) polymorphisms are associated with the outcomes of hepatitis B virus (HBV) infection in Chinese Han population. METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the polymorphisms of Fok I locus in exon 2 and Taq I locus in exon 9 of VDR gene. One hundred and eighty-four chronic hepatitis B patients and 205 asymptomatic HBV carriers were recruited to make the comparison of frequencies of genotype and haplotype of the VDR gene between the patients and the carriers. RESULTS: The univariate analysis showed a significant difference in Fok I polymorphism between chronic hepatitis B patients group and asymptomatic HBV carriers group. The FF genotype frequency in chronic hepatitis B patients group was 44.6%,higher than 31.7% in asymptomatic HBV carriers group (P<0.05). After adjusting the confounders by multiple logistic regression analysis, the result still showed a significant difference in Fok I site polymorphism between chronic hepatitis B patients group and asymptomatic HBV carriers group (OR=1.95, P<0.05). The FT haplotype frequency in chronic hepatitis B patients group was higher than that in asymptomatic HBV carriers group (OR=1.45, P<0.05). The fT haplotype frequency in chronic hepatitis B patients group was lower than that in asymptomatic HBV carriers group (OR=0.72, P<0.05). CONCLUSION: VDR gene polymorphism may be an influence factor of genetic susceptibility to HBV infection.

[Association of haplotype formed on HLA-DRB1 and HLA-DQA1 alleles with outcomes of hepatitis B virus infection].

OBJECTIVE: To assess the association of haplotype of HLA-DRB1 and HLA-DQA1 alleles with outcomes of hepatitis B virus infection in Han population of north China. METHODS: Two hundred and seven chronic hepatitis B (HB) patients, two hundred and twelve chronic asymptomatic hepatitis B virus (HBV) carriers (HBV carrier) and one hundred and forty-eight self-limited HBV infection were investigated for HLA-DRB1 and HLA-DQA1 alleles by sequence specific-polymerase chain reaction (PCR-SSP). RESULTS: The frequency of DRB1*04-DQA1*0301 haplotype was 10.03% in self-limited HBV infection subjects, significantly higher than that in chronic HB patients (3.66%) (P=0.0005)ûthe frequency of DRB1*15/*16-DQA1*0102 haplotype was 6.80% in self-limited HBV infection subjects, significantly higher than 1.94% in chronic HB patients (P=0.0012) and 1.65% in asymptomatic HBV carriers (P=0.0004)ûwhile the frequency of DRB1*04-DQA1*0302 haplotype was 3.10% in chronic HB patients, higher than that in self-limited HBV infection subjects (0.39%) (P=0.0077). CONCLUSION: Individuals with different haplotypes composed of HLA-DRB1 and HLA-DQA1 might have different outcomes of HBV infection.

[Association of polymorphisms of human leucocyte antigen -DRB1 and -DQA1 allele with outcomes of hepatitis B virus infection in Han population of north China].

OBJECTIVE: To assess the association of polymorphisms of human leucocyte antigen (HLA) -DRB1 and -DQA1 region allele with outcomes of hepatitis B virus (HBV) infection in Han population of north China. METHODS: A total of 207 chronic hepatitis B (HB) patients, 212 chronic asymptomatic HBV carriers (HBV carrier), and 148 self-limited HBV infection were recruited to examine the association between gene polymorphisms and outcomes of HBV infection. Polymerase chain reaction-sequence specific primers (PCR-SSP) technique was used to genotype HLA-DRB1 and HLA-DQA1 loci. RESULTS: The frequency of HLA-DQA1 * 0301 in chronic HB patients (14.81%) was significantly lower than those in HBV carriers (25.24%) and self-limited HBV infection subjects (25.00%) (Pc = 0.002; Pc = 0.007). The frequency of HLA-DQA1 * 0102 in self-limited HBV infection subjects (8.78%) was significantly higher than those in chronic HB patients (2.18%) and HBV carriers (1.89%) (Pc = 0.000; P = 0.000). In addition, the frequency of HLA-DQA1 * 0302 in self-limited HBV infection subjects (4.05%) was significantly lower than that in chronic HB patients (11.41%) (Pc = 0.005). HLA-DQA1 * 0302 was demonstrated to be risk factors of chronic HBV (OR = 3.913, P = 0.0006), while HLA-DQA1* 0102 and HLA-DQA1 * 0301 to be protective factors against chronic HBV (OR = 0.200, P = 0.0004; OR = 0.258, P = 0.0000) after age, sex, smoking and drinking were adjusted by logistic regression analysis. There were positive interactions between drinking and HLA-DQA1 * 0102 [interaction index (II) = 1.49] or HLA-DQA1 * 0302 (II = 12.12). There were negative interactions between drinking and HLA-DQA1 * 0301 (II = 0.78) CONCLUSIONS: The subjects with HLA-DQA1 * 0302 allele have an increased risk to chronic HB infection compared with other subjects without this allele, while HLA-DQA1 * 0301 and HLA-DQA1 * 0102 are associated with HBV clearness. Gene-environment interaction can affect the outcomes of HBV infection.

[Association of TNFA polymorphisms with the outcomes of HBV infection].

OBJECTIVE: To explore whether the TNFA promoter single nucleotide polymorphisms (SNPs) are associated with the outcomes of hepatitis B virus(HBV) infection in Chinese Han population. METHODS: One hundred and forty-eight self-limited HBV infection subjects and 207 chronic hepatitis B patients were recruited. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequence specific primer-PCR(PCR-SSP) were used to detect the SNPs of five sites in TNFA promoter (-238G/A, -308G/A, -857C/T, -863C/A, -1031T/C). The frequency distributions of genotypes and haplotypes in different groups were analyzed by EPI and EH programs. RESULTS: The frequencies of -238GG genotype in chronic hepatitis B patients were significantly higher than that in self-limited infection subjects (P=0.02). The frequencies of -857TT genotype in chronic hepatitis B patients were clearly lower than that in self-limited infection subjects (P=0.02). Haplotypic frequencies of GGCCT (-238/-308/-857/-863/-1031) in chronic hepatitis B patients was significantly lower than that in self-limited infection subjects (P=0.03), and the frequencies of haplotype GGCAT or GGTAT in chronic hepatitis B patients were clearly higher than those in self-limited infection subjects (P=0.0001; P=0.004). CONCLUSION: TNFA promoter polymorphisms are important host genetic factors affecting the outcomes of HBV infection.

Association of -238G/A polymorphism of tumor necrosis factor-alpha gene promoter region with outcomes of hepatitis B virus infection in Chinese Han population.

AIM: To clarify whether -238G/A polymorphism of tumor necrosis factor-alpha (TNF-alpha) gene promoter region was associated with outcomes of hepatitis B virus (HBV) infection in Han population of northern China, and to analyze the gene-environment interaction between -238G/A polymorphism and cigarette smoking or alcohol consumption. METHODS: A case-control study was conducted to analyze the association of TNF-alpha gene promoter polymorphism with HBV infection outcomes. A total of 207 patients with chronic hepatitis B (HB) and 148 cases of self-limited HBV infection from Ditan Hospital and Shunyi District Hospital in Beijing, respectively were recruited. History of smoking and alcohol drinking was inquired by a questionnaire. The -238G/A polymorphism of TNF-alpha gene promoter was genotyped by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP). RESULTS: The frequencies of GG and GA genotypes were 98.07% and 1.93% in chronic HB patients and 93.24% and 6.76% in self-limited HBV infection individuals, respectively (chi(2)=5.30, P=0.02). The frequency of G allele was significantly higher in patients with chronic HB that in individuals with self-limited HBV infection (99.03% vs 96.62%, chi(2)=5.20, P=0.02). Only modestly increased risk of onset of chronic HB was found in smokers (OR=1.40, 95% CI: 0.87-2.28, P=0.14) and drinkers (OR=1.26, 95%CI: 0.78-2.05, P=0.32). There was a positive interaction between genotype GG and cigarette smoking with an interaction index (II) of 2.95, or alcohol consumption with an II of 1.64. CONCLUSION: The -238G/A polymorphism of TNF-alpha gene promoter region is independently associated with different outcomes of HBV infection.