Genomic heterogeneity of hepatitis B virus (HBV) and outcome of perinatal HBV infection

Association between Human Leukocyte Antigen-DQ Polymorphisms and Treatment Response in Chronic Hepatitis B Egyptian Population: A Prospective Study

Background & Aims:

Several studies, in different populations, have focused on the role of HLA-DQ gene polymorphism in the pathogenesis of HBV infection. However, these findings are still controversial. This study aimed to determine HLA-DQ polymorphism in Chronic HBV patients and its impact on the response to antiviral therapy.

Methods:

This study was carried out on a total number of 188 participants, they were subdivided as follows: Group I (patients’ group): included 97 patients with chronic hepatitis B viral infection that was further subdivided according to response to treatment into responder and non-responder subgroups, Group II (Control group): included 91 normal healthy subjects who were matched to the patient group by sex and age. PCR (Polymerase Chain Reaction) testing, for HBV-DNA, was done for all participants enrolled in the study to measure the viral virus load before and after treatment. HLA- DQ polymorphism allelic discrimination assay was assayed using the Real-time equipment.

Results:

In a general analysis for the SNP rs7453920, the overall genotypes frequencies were 37% for A/A, 60.6% for A/G, and 37% for G/G. The G alleles of HLA-DQ rs7453920 were significantly increased in chronic HBV infection patients. A total of 77 (79.4%) patients were responders. Among this group, 72.7% were male, and the average age was 38.59 ±9.15 years. On evaluation of the association between polymorphisms in HLA-DQ gene and treatment response, the results indicated that response to treatment declined when patients were carrying the more unfavorable rs 7453920 GG with a response rate of 64%. Patients carrying the mutant allele AG, or the wild type allele AA were more likely to achieve a higher rate of response (84.8% and 83.3%, respectively).

Conclusion:

The presence of HLA-DQB2 rs 7453920-G serves as a risk factor for chronic HBV infection and treatment failure in the Egyptian population.

HLA-DQA1 & DQB1 variants associated with hepatitis B virus-related chronic hepatitis, cirrhosis & hepatocellular carcinoma

Background & objectives:

Clinical outcome after hepatitis B virus (HBV) exposure varies extremely from spontaneous clearance to chronic hepatitis B and often progresses to liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Host genetic factor plays an important role in the regulation of immune response. This study was aimed to investigate whether HLA class II DQA1 and DQB1 gene polymorphism were associated with chronic hepatitis B infection and in the development of HBV-related LC and HCC.

Methods:

DQA1 and DQB1 allele polymorphism were studied in 187 patients with HBV-related liver diseases (which included 73 chronic hepatitis B, 84 LC and 30 HCC patients) and 109 controls who had spontaneously recovered from HBV infection using polymerase chain reaction amplification with sequence-specific primers.

Results:

Our data suggested that DQA1*0101/2/4 [odds ratio (OR)=2.78; P^c=0.003], DQA1*0103 (OR=2.64; P^c=0.0007) and DQB1*0302/3 (OR=2.15; P^c=0.01) were associated with the protection from chronic HBV infection, whereas DQB1*0402 (OR=0.25; P^c=0.001) showed susceptible effect on chronic HBV infection. DQB1*0601 (OR=3.73; P^c=0.006) conferred protective effect from developing LC; similarly, DQB1*0302/3 (OR=5.53; P^c=0.05) and DQB1*0402 (OR=0.00; P^c=0.001) conferred protective effect from developing HCC. However, DQA1*0601 and DQB1*0503 showed susceptible effect on chronic HBV infection; these associations were no longer significant after Bonferroni correction.

Interpretation & conclusions:

Our results revealed HLA-DQA1*0101/2/4 - DQA1*0103 - DQB1*0302/3 and DQB1*0601 as protective and DQB1*0402 as risk alleles. The study suggests that various subtypes of HLA-DQA1 and DQB1 are associated with both HBV clearance and development of chronic HBV infections.

Correlations between mitochondrial DNA haplogroup D5 and chronic hepatitis B virus infection in Yunnan, China

Mitochondrial abnormality is frequently reported in individuals with hepatitis B virus (HBV) infection, but the associated hosts’ mitochondrial genetic factors remain obscure. We hypothesized that mitochondria may affect host susceptibility to HBV infection. In this study, we aimed to detect the association between chronic HBV infection and mitochondrial DNA in Chinese from Yunnan, Southwest China. A total of 272 individuals with chronic HBV infection (CHB), 310 who had never been infected by HBV (healthy controls, HC) and 278 with a trace of HBV infection (spontaneously recovered, SR) were analysed for mtDNA sequence variations and classified into respective haplogroups. Haplogroup frequencies were compared between HBV infected patients, HCs and SRs. Haplogroup D5 presented a higher frequency in CHBs than in HCs (P = 0.017, OR = 2.87, 95% confidence interval [CI] = (1.21–6.81)) and SRs (P = 0.049, OR = 2.90, 95% CI = 1.01–8.35). The network of haplogroup D5 revealed a distinct distribution pattern between CHBs and non-CHBs. A trend of higher viral load among CHBs with haplogroup D5 was observed. Our results indicate the risk potential of mtDNA haplogroup D5 in chronic HBV infection in Yunnan, China.

24 year outcomes of hepatitis B vaccination in Hangzhou, China

To evaluate the impact of the universal infant HepB vaccination program on hepatitis B virus infection in Hangzhou, China. Hepatitis B incidences and HepB vaccination rates of Hangzhou from 1990 to 2003 were acquired from the historical paper-documents, while which were derived from China Information System for Diseases Control and Prevention and Zhejiang Information System for Immunization Program respectively from 2004 to 2013. A serology survey among person aged 0-59 y was conducted in Hangzhou in 2006. Participants were selected by stratified, multi-stage random sampling. Serum specimens were tested for HBsAg, anti-HBs , anti-HBc , HBeAg and anti-HBe by ELISA. For the past 24 years, hepatitis B incidence and mortality of Hangzhou declined dramatically (χ(2) = 3.2 × 10(4); χ(2) = 172.443; both P for trend < 0.001). Both urban and rural incidence descended (χ(2)urban = 1.904 × 10(4); χ(2)rural = 1.633 × 10(4) ; both P for trend < 0.001).Hepatitis B patients mainly concentrated in 20-40 y old; workers and farmers were the main infection occupations, which was varies in different years (χ(2) = 1.619 × 10(3), P < 0.001). Significant association was found between incidence of hepatitis B and HepB vaccination rate (r = 0 .946, χ(2) = 11.813, Pfor trend = 0.001). A total of 5605 participants aged 0-59 y included in this serological survey. The prevalence of HBsAg, anti-HBs, anti-HBc, HBeAg and anti-HBe were 6.19%, 45.83%, 57.25%, 0.62%, and 4.37%, respectively. Hangzhou has successfully integrated the HepB into routine immunization programs and this has had a significant impact on decreasing the incidence of hepatitis B infection.

The clinical implications of hepatitis B virus genotypes and HBeAg in pediatrics

Although a successful vaccine against HBV has been implemented in 184 countries, eradication of hepatitis B virus (HBV) is still not on the horizon. There are over 240 million chronic carriers of HBV globally. The risk of developing chronic hepatitis ranges from >90% in newborns of hepatitis Be antigen (HBeAg)‐positive mothers, 25%–35% in children under 5 years of age and <5% in adults. HBeAg, a non‐particulate viral protein, is a marker of HBV replication. This is the only HBV antigen to cross the placenta, leading to specific unresponsiveness of helper T cells to the capsid protein and HBeAg in newborns. HBeAg is tolerated in utero and acts as a tolerogen after birth. Perinatal transmission is frequent when mothers are HBeAg‐positive, whereas it occurs less frequently when mothers are HBeAg‐negative. Sequence heterogeneity is a feature of HBV. Based on an intergroup divergence >7.5% across the complete genome, HBV is classified phylogenetically into at least nine genotypes. With between ~4% and 8% intergroup nucleotide divergence, genotypes A–D, F, H and I are classified further into subgenotypes. HBV genotypes/subgenotypes may have distinct geographical distribution and can develop different mutations in the regions of the HBV genome that code for HBeAg. These differences can be related to the role of HBV genotypes to the natural history of infection and mode of transmission. Thus genotypes/subgenotypes of HBV can be responsible for the different natural history of infection and modes of transmission in children, found in various regions of the world, where different genotypes/subgenotypes prevail. Copyright © 2016 John Wiley & Sons, Ltd.

Management of mother-to-child transmission of hepatitis B virus: Propositions and challenges

Chronic hepatitis B virus (HBV) infection due to mother-to-child transmission (MTCT) during perinatal period remains an important global health problem. Despite standard passive-active immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine in neonates, up to 9% of newborns still acquire HBV infection, especially these from hepatitis B e antigen (HBeAg) positive mothers. Management of HBV infection in pregnancy still need to draw careful attention because of some controversial aspects, including the failure of passive-active immunoprophylaxis in a fraction of newborns, the effect and necessity of periodical hepatitis B immunoglobulin (HBIG) injection to the mothers, the safety of antiviral prophylaxis with nucleoside/nucleotide analogs, the benefit of different delivery ways, and the safety of breastfeeding. In this review, we highlight these unsettled issues of preventive strategies in perinatal period, and we further aim to provide an optimal approach to the management of preventing MTCT of HBV infection.

Study of the relationship in pregnant women between hepatitis B markers and a placenta positive for hepatitis B surface antigen

AIMS

A placenta with hepatitis B virus (HBV) is one of the main reasons for transplacental transmission during pregnancy. This study aims to explore the factors influencing the presence of hepatitis B surface antigen (HBsAg) in the placenta and the synergistic effect of these factors.

METHODS

A total of 155 placentae and blood specimens were collected from HBsAg-positive mothers and their newborns. HBsAg in placenta was detected using the immunohistochemistry method. HBV serum markers were detected using enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods.

RESULTS

The results showed that hepatitis B e antigen (HBeAg) positive, or HBV DNA positive status, is significantly associated with an HBsAg-positive placenta. A synergistic effect was present. The hazard ratio for a HBsAg-positive placenta in mothers with HBeAg and HBV DNA was 1.97 times higher than the sum of the independent relative risk of each separate effect (synergy index, S=1.97). There was a statistically significant association between HBsAg in newborns and HBsAg in placenta, and the risk of newborns with HBsAg was greater (odds ratio values 3.33 and 5.31, respectively) when placental cells close to the fetal side were HBsAg positive.

CONCLUSIONS

Being positive for HBeAg and/or HBV DNA are significant risk factors for HBsAg in the placenta. HBsAg can pass through the placenta via cellular transfer, possibly contributing to transplacental transmission.

Infantile hepatitis B in immunized children: risk for fulminant hepatitis and long-term outcomes

BACKGROUND

Infantile hepatitis B after neonatal immunoprophylaxis is a rare yet distinct disease. This study aimed to analyze the long-term outcomes and risk factors in immunized infants with hepatitis B.

METHODS

The clinical parameters and outcomes of 41 infants born after universal immunization, and admitted for HBV-positive hepatitis were studied. All patients were followed for at least 6 months (median  = 4.4 years, range 0.6-18.1 years). Patient survival, changes of HBsAg and HBeAg status, and complications were analyzed.

RESULTS

Among the 41 cases (32 males, 9 females), 21 presented with fulminant hepatitis (FH), and 20 with non-fulminant hepatitis (NFH). Ninety-five percent (36/38) of the mothers were positive for hepatitis B surface antigen (HBsAg). Multivariate analyses revealed younger age of onset (age <7 months) and negative maternal hepatitis B e antigen (HBeAg) were associated with FH (p = 0.03 and p = 0.01, respectively). An infantile fulminant hepatitis B risk score using maternal/infant HBeAg positivity and onset age was proposed. Among the FH cases, the rate of mortality, HBsAg clearance, and chronic HBV infection were 47.6%, 38.1%, and 14.3%, respectively. Among the NFH cases, 35% developed chronic infection. Of the 9 chronically infected children received long-term follow-up, 8 had HBeAg seroconversion before 4 years of age. One case of FH developed hepatocellular carcinoma 14 years later.

CONCLUSIONS

Maternal HBsAg + /HBeAg- and early onset age were risk factors for FH in immunized infants. A significant portion of patients with FH or NFH evolve to chronic HBV infection, with HBeAg seroconversion in young childhood. Close surveillance for hepatocellular carcinoma is warranted in patients surviving infantile hepatitis B.

Rather than Rs1800796 polymorphism, expression of interleukin-6 is associated with disease progression of chronic HBV infection in a Chinese Han population

Interleukin-6 plays an important role in chronic inflammation as well as tumor growth and progression. Here, a case-control study was undertaken to investigate the association of rs1800796 polymorphism of IL-6 gene and serum levels with disease progression of chronic HBV infection. Rs1800796 polymorphism was genotyped in 641 Chinese Han patients with chronic HBV infection, including 23 IT, 25 IC, 292 CHB, 153 LC, and 148 HCC patients and 265 healthy controls. Serum IL-6 levels were measured in 23 IT, 25 IC, 47 CHB, 41 LC, and 49 HCC patients and 45 healthy controls, and the classifications of HCC were accorded to BCLC staging system. We found no significant association between rs1800796 polymorphism and disease progression of chronic HBV infection; however, serum IL-6 levels showed significant statistical differences between patients with CHB, LC, and HCC. Moreover, statistical differences can be observed in patients with terminal stage HCC compared with those of early to intermediate or advanced stage HCC. Our findings suggest that rs1800796 polymorphism unlikely contribute significantly to affect the progression of chronic HBV infection, and serum IL-6 levels can act as a useful indicator for disease progression and severity of chronic HBV infection.

Hepatitis B surface antigen prevalence among 12,393 rural women of childbearing age in Hainan Province, China: a cross-sectional study

Background

Hepatitis B virus (HBV) infection is highly endemic in China and it threats human health seriously. The hepatitis B surface antigen (HBsAg) prevalence among women of childbearing age plays an important role in mother to child transmission of HBV, as 30% ~50% of chronic carriers can be attributed to maternal-infantile transmission. However, there are few studies which have reported on the prevalence of HBsAg among women of childbearing age in China. This study aimed to determine the prevalence of HBsAg and its associated risk factors among rural women of childbearing age in Hainan, which is the highest hepatitis B virus endemic province in China.

Methods

A cross-sectional, population-based study, which included 12393 rural women aged 15 ~ 49 years, enrolled by a multistage stratified cluster sampling, was carried out in Hainan province, China, from November 2007 to December 2008. Blood samples were obtained from each study participant, and screened for HBsAg.

Results

The overall HBsAg prevalence of childbearing age women was 9.51%. Risk factors for HBsAg positivity among rural women were: lower education level (OR=1.206), lower family monthly income (OR=1.233), having an HBsAg-positive family member (OR=1.300), without an immunization history (OR=1.243), tattooing (OR=1.190), body piercing (OR=1.293), vaginoscopy history (OR=1.103) and history of induced abortion (OR=1.142).

Conclusions

There is a high HBsAg seroprevalence rate among rural women of childbearing age in Hainan province. Hence, it is necessary to take preventive measures to reduce the seroprevalence of HBsAg and to control its associated risk factors.

Chronic HBV infection among pregnant women and their infants in Shenyang, China

Background

The main transmission route of the hepatitis B virus (HBV) is mother to child transmission and contributes significantly to chronic HBV infection. Even though immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine is administrated to neonates whose mothers are hepatitis B surface antigen (HBsAg) positive, about 10% of the neonates suffer from HBV infection in their early life.

Objectives

To survey chronic HBV infection among pregnant women and their infants and analyze the reason for immunoprophylaxis failure.

Methods

Serum HBsAg was tested in all pregnant women. HBVDNA and other serum HBV markers including hepatitis B e antigen (HBeAg), hepatitis B core antibody (anti-HBc) and hepatitis B surface antibody (anti-HBs) were tested among HBsAg positive pregnant women. All infants whose mothers were HBsAg positive were vaccinated with a standard immunoprophylaxis. Serum HBV markers and HBVDNA were tested among these infants at 7 months of age. HBV genotypes were analyzed among the infants and pregnant women who were HBVDNA positive.

Results

The prevalence of HBsAg, anti-HBc and anti-HBs among 4,536 pregnant women was 5.49%, 29.65% and 58.55%, respectively. The prevalence of HBsAg, anti-HBc and anti-HBs among pregnant women older than 20 years of age was significantly different compared to pregnant women younger than 20 years of age (4.54, 5.69 and 0.61 times, prevalence older vs. younger, respectively. P<0.05, 0.01, 0.05, respectively). Among 249 HBsAg positive pregnant women, 167 (67.07%) were HBeAg positive, 204 (81.93%) were HBVDNA positive and only 37 (14.86%) had HBVDNA >10⁷ IU/ml. Among the infants whose mothers were HBsAg positive, 214 (85.94%) infants were anti-HBs positive. There were 12 (4.82%) infants who were HBsAg and HBVDNA positive, and all 12 of these infants mothers were HBeAg positive and had HBVDNA >10⁷ IU/ml. Genotypes B and C were present among 165 pregnant women and genotype C was present in 85 pregnant women. There were 12 infants who were HBsAg positive and had the same HBV genotypes as their mothers. There was a significant difference in genotypes between the pregnant women whose infants were infected with HBV compared to those without HBV infection (P < 0.05).

Conclusions

There was a significant decline in HBsAg prevalence among pregnant women and their infants in Shenyang. Genotype C might be a risk factor for mother to child transmission of HBV.

Molecular analysis of hepatitis B virus associated with vaccine failure in infants and mothers: a case-control study in Thailand

Perinatal transmission of hepatitis B virus (HBV) has been controlled incompletely despite adequate immunoprophylaxis in infants. The aim of this study was to characterize virological factors of HBV associated with vaccine failure in Thailand. Sera of 14 infected infants (13 HBeAg-positive and one HBeAg-negative) with vaccine failure and their respective mothers (group M1) were tested quantitatively for HBV DNA by real-time PCR, HBV genotypes and mutations were characterized by direct sequencing. Sera collected from 15 HBeAg-positive (group M2) and 15 HBeAg-negative (group M3) mothers whose infants had been vaccinated successfully served as controls. The results showed that group M1 and group M2 mothers had equal titers of HBV DNA but higher titers than group M3. All infected infants and their respective mothers had the same HBeAg status and HBV genotypes. DNA analysis in a pair of HBeAg-negative infant and mother revealed that both were infected with an HBV precore mutant (G1896A). Escape mutants in the "a" determinant region (residues 144 and 145) were detected in two (14%) infected infants. The prevalence of BCP mutations/deletions in groups M2 and M3 was higher significantly than in group M1 (P = 0.022 and P < 0.001, respectively). In conclusion, instead of the HBeAg status, a high titer of HBV DNA in mothers was the major contributor to perinatal transmission of HBV. Escape mutants might be associated with vaccine failure in some infants. BCP mutations/deletions in mothers might contribute to the prevention of mother-to-infant transmission of HBV.

Effects of maternal screening and universal immunization to prevent mother-to-infant transmission of HBV

BACKGROUND & AIMS

Mother-to-infant transmission is the major cause of hepatitis B virus (HBV) infection among immunized children. There has been much debate about screening pregnant women and administering hepatitis B immunoglobulin (HBIG) to newborns. We analyzed the rate of HBV infection among children born to hepatitis B surface antigen (HBsAg)-positive mothers and whether HBIG administration reduces transmission.

METHODS

We analyzed data from 2356 children born to HBsAg-positive mothers, identified through prenatal maternal screens. In addition to HBV vaccines, HBIG was given to all 583 children with hepatitis B e antigen (HBeAg)-positive mothers and to 723 of 1773 children with HBeAg-negative mothers. Serology tests for HBV were performed from 2007 to 2009, when children were 0.5-10 years old.

RESULTS

A significantly greater percentage of children with HBeAg-positive mothers tested positive for antibodies against the hepatitis B core protein (16.76%) and HBsAg (9.26%) than children with HBeAg-negative mothers (1.58% and 0.29%, respectively; P < .0001 and <.001). Among the HBV-infected children, the rate of chronicity also was higher among children with HBeAg-positive mothers than children with HBeAg-negative mothers (54% vs 17%; P = .002). Similar rates of antibodies against the hepatitis B core protein (0.99% and 1.88%; P = .19) and HBsAg (0.14% and 0.29%; P = .65) were noted in children born to HBeAg-negative mothers who were or were not given HBIG. Infantile fulminant hepatitis developed in 1 of 1050 children who did not receive HBIG (.095%).

CONCLUSIONS

Children born to HBeAg-positive mothers are at greatest risk for chronic HBV infection (9.26%), despite immunization. Administration of HBIG to infants born to HBeAg-negative mothers did not appear to reduce the rate of chronic HBV infection, but might prevent infantile fulminant hepatitis. Screening pregnant women for HBsAg and HBeAg might control mother-to-infant transmission of HBV.

HEPATITIS B AND PREGNANCY, THE SCIENTIFIC BASIS FOR PERINATAL PREVENTION

Hepatitis B and its complications are one of the major global health problems. Around 2 billion individuals are infected by hepatitis B virus (HBV) worldwide, more than 350 million are chronically infected, and approximately 15 to 40 percents of them will develop serious complications such as liver cirrhosis, hepatic failure, or hepatocellular carcinoma (HCC). The worldwide prevalence of chronic HBV infection ranges from 0.1 to 20 percent and varies widely in different geographic areas. According to the prevalence rate, WHO has classified countries into 3 levels: high areas (>8%) such as Africa, Asia, Western Pacific and Middle East; intermediate areas (2–8%) such as South America and Eastern Europe, and low areas (<2%) such as Western Europe, North America, and Australia.

Survey of HBsAg-positive pregnant women and their infants regarding measures to prevent maternal-infantile transmission

BACKGROUND

Intrauterine infection is the main contributor to maternal-infantile transmission of HBV. This is a retrospective study of 158 HBsAg-positive pregnant women who delivered children from Jan 1st, 2004 to Dec.31th, 2006 in Wuhan City, China. We investigated the measures taken to prevent maternal-infantile transmission of hepatitis B virus and the infection status of children.

METHODS

HBsAg-positive pregnant women were selected by a random sampling method when they accepted prenatal care in district-level Maternal and Child Health Hospitals. On a voluntary basis, these women completed questionnaires by face-to-face or phone interviews. The collected data were used to evaluate the immunization programs that pregnant women had received for preventing hepatitis B maternal-infantile transmission.

RESULTS

Among the 158 women, 143(90.5%) received Hepatitis B immune globulin during pregnancy, and 86.0% of their children were given Hepatitis B immune globulin and Hepatitis B vaccine. The rate of cesarean section was 82.3%, and 28.5% of these were aimed at preventing HBV infection. The rate of bottle feeding was 51.9%, and 89.0% of bottle feeding cases were for the purpose of preventing HBV infection. There were 71 cases of participants who were HBeAg-positive. Compared with the HBsAg+ HBeAg- group (only HBsAg-positive), the HBsAg + HBeAg+ group (HBsAg-positive and HBeAg-positive) had significantly higher rates of the caesarean section and bottle feeding resulting from hepatitis B (P < 0.05). Five cases were HBsAg-positive by Umbilical Cord Blood detection. The intrauterine infection rate of newborns was 6.7%. The chronic HBV rate of children was 4.0%.

CONCLUSION

Most HBsAg positive pregnant women have a growing awareness of maternal-infantile transmission of Hepatitis B virus and are receiving some form of preventative treatment, like combined immunization. Caesarean and bottle feeding are very common, often primarily to prevent transmission. Relatively few intrauterine infections were identified in this sample, but many infants did not appear to seroconvert after vaccination.

A phylogenetic study of hepatitis B virus in chronically infected Brazilian patients of Western and Asian descent

BACKGROUND

Hepatitis B virus (HBV) causes one of the most important chronic viral infections worldwide. HBV is classified into eight genotypes whose epidemiology varies geographically. In Brazil, genotypes A, D, and F are more frequent, while in East Asia, genotypes B and C predominate. Several studies showed that immigrants retain the HBV infection pattern of their ancestral country.

PURPOSE

To identify HBV genotypes infecting chronic carriers in Brazilian families of Western and Asian descent by Hepatitis B surface antigen gene sequencing and analyze the route of viral transmission by phylogenetic analysis of viral sequences.

METHODS

Eighty-seven people chronically infected with HBV were separated into two groups: Western descent (27) and Asian descent (60). Surface and pre-core/core genes were amplified from serum HBV-DNA and sequences were subjected to phylogenetic analysis.

RESULTS

HBV genotype A was found in 74% of Western subjects, while genotype C was found in 94% of Asian patients. Thirty-eight percent of Western families were infected with HBV with similar pre-core/core sequences, while only 25% of Asian families showed similarity in these sequences.

CONCLUSIONS

Phylogenetical analysis of pre-core/core HBV gene suggested intra-familial transmission of HBV in 38% of Western families and 25% of Asian families. Analysis of HBsAg gene sequences helped to define the HBV genotype but did not allow inferring route of transmission as its sequences showed a smaller phylogenetic signal than pre-core/core sequences. Chronic HBV carriers of Asian descent born in or living in Brazil were infected with the same HBV genotype predominant in their ancestral country.

Association of polymorphisms of human leucocyte antigen-DQA1 and DQB1 alleles with chronic hepatitis B virus infection, liver cirrhosis and hepatocellular carcinoma in Chinese

To investigate whether human leucocyte antigen (HLA) class II DQA1 and DQB1 gene polymorphisms are associated with chronic hepatitis B virus (HBV) infection and development of HBV-related liver cirrhosis (LC) and hepatocellular carcinoma (HCC), we detected the DQA1 and DQB1 allele polymorphisms in 168 HBV carriers (including 48 chronic hepatitis B, 42 LC and 78 HCC patients) and 100 controls who had recovered from HBV infection by using polymerase chain reaction amplification with sequence-specific primers (PCR-SSP). Our data suggest that DQA1*0102 and DQA1*0104 were associated with protection from chronic HBV infection (P(c) = 0.003) and development of LC (P(c) = 0.001), respectively, whereas DQB1*0201 conferred susceptible effect on chronic HBV infection (P(c) = 0.008). We also found that DQA1*0601, DQB1*0601 and DQA1*0201 showed some susceptible effect on chronic HBV infection and LC, respectively, however, these associations were no longer significant after Bonferroni correction (P(c) = 0.390, P(c) = 0.475 and P(c) = 0.140, respectively). No significant association has been found between DQA1 and DQB1 alleles and development of HCC. These results indicate that different subtypes of HLA-DQA1 and DQB1 are associated with development of chronic HBV infection and LC, respectively, in Han Chinese population.

Maternofetal transmission of hepatitis B virus genotype E in Ghana, west Africa

To determine whether maternofetal transmission of hepatitis B virus (HBV) is a common route of infection leading to chronic infection in west Africa, plasma samples, obtained at delivery from 1368 pregnant Ghanaian women and paired umbilical cord blood or newborn whole blood samples, were tested for HBV surface antigen (HBsAg) and DNA. A 16 % prevalence of HBV chronic carriers, defined as detectable HBsAg and/or HBV DNA, was found, >80 % contained less than 1 x 10(4) IU ml(-1) HBV DNA and 99 % were infected with genotype E strains. HBV maternofetal transmission was documented in 17 out of 204 (8.3 %) paired HBV carrier women-cord blood/newborn samples. The rate of transmission was 55 % and 3.3 % when maternal viral load was above or below 1 x 10(4) IU ml(-1), respectively (P=0.0008). Maternofetal transmission of HBV genotype E was estimated to account for 8 % of the cases of chronic HBsAg carriers. Six women with low viral load at delivery (five <20 IU ml(-1)) and anti-HBe (hepatitis B e antigen) transmitted HBV. Surprisingly, while non-transmitted low viral load strains had 79 % mutations at position 1896 of HBV genome, transmitted strains were all wild-type despite anti-HBe presence (P=0.0041), suggesting the possible role of HBeAg as risk factor for HBV maternofetal transmission. The relative risk of maternofetal transmission was 2.4 when pregnant women carried high viral load and 11.5 when carrying wild-type strains at position 1896, irrespective of viral load. We conclude that viral load and pre-core wild-type at position 1896 are two independent risk factors for HBV genotype E maternofetal transmission, which remains a minor contributor to high prevalence of chronic infection.

Putative association of Fas and FasL gene polymorphisms with clinical outcomes of hepatitis B virus infection

OBJECTIVE

Fas/FasL polymorphisms, which are related to apoptosis, might influence the clearance of hepatitis B virus (HBV) infection and the occurrence of hepatocellular carcinoma (HCC). This study was performed to determine whether Fas and FasL promoter polymorphisms are associated with clinical outcome in chronic HBV infection.

METHODS

A total of 1,095 Korean subjects were prospectively allocated to two different groups: 'the chronic carrier group' (CC; n = 666), who were repeatedly hepatitis B surface antigen (HBsAg)-positive, and 'the spontaneous recovery group' (SR; n = 429), who were HBsAg-negative with antibodies to HBsAg and hepatitis B core antigen. In addition, the CC group was subcategorized into chronic hepatitis and HCC subgroups. Fas promoter polymorphisms at -1377G>A and -670A>G and the FasL promoter polymorphism at -844C>T were analyzed for and the genotype distributions of subjects were compared.

RESULTS

There were no significant associations between Fas or FasL promoter polymorphism with the HBV clearance and HBeAg clearance. However, -1377G>A in Fas promoter region showed protective effect to HCC occurrence (RH = 0.70, p = 0.03).

CONCLUSIONS

Fas-1377G>A polymorphisms might be involved in the pathogenesis of human HCC.

SPP1 polymorphisms associated with HBV clearance and HCC occurrence

BACKGROUND

Secreted phosphoprotein-1 (SPP1) is a secreted arginine-glycine-aspartate (RGD)-containing phosphoprotein. SPP1 is overexpressed in metastatic hepatocellular carcinoma (HCC), and therefore could act as both a diagnostic marker and a potential therapeutic target for metastatic HCC. We investigated the genetic polymorphisms in SPP1 to determine whether it is a potential candidate gene for a host genetic study of hepatitis B virus (HBV) clearance and HCC occurrence.

METHODS

Five genetic variants in SPP1 were genotyped by TaqMan assay and the genetic association with HBV clearance and HCC occurrence was analysed.

RESULTS

Genetic association analysis of SPP1 polymorphisms with an HBV cohort (n = 1,069) from the Korean population revealed that the most common haplotype (SPP1-ht2 [T-T-C-T-A]) was associated with HBV clearance. The frequency of the SPP1-ht2-bearing genotype in the chronic carrier (CC) group was higher than in the spontaneously recovered (SR) group (OR = 1.44 [95% CI 1.11-1.87], P = 0.006, P(corr) = 0.02). By Cox relative hazard analysis, both SPP1-ht2 and -1,800G > T were associated with age of HCC occurrence among chronic hepatitis patients, e.g. ht2/h2- and 1800T/T-bearing patients showed earlier progression to HCC than did others (RH = 1.85, P = 0.004, P(corr) = 0.01 and RH = 1.85, P = 0.003, P(corr) = 0.01, respectively).

CONCLUSION

Our findings suggest that SPP1 polymorphisms might be among the genetic factors for HBV clearance and/or HCC occurrence.

Maternal hepatitis B virus (HBV) DNA positivity and sexual intercourse are associated with HBV intrauterine transmission in China: a prospective case-control study

BACKGROUND AND AIM

Hepatitis B virus (HBV) intrauterine transmission from infected mothers contributes significantly to the persistence of the high number of HBV carriers. The aim of this study was to identify potential risk factors for HBV intrauterine transmission.

METHODS

A case-control study was performed on pregnant women tested positive for HBsAg at Shaanxi Maternal and Neonatal Health Hospital, Xi'an, China, from September 2002 to October 2004. Serum samples were taken from infected women and their newborn infants and used for the detection of HBsAg. A structured standard questionnaire was used to collect demographic, medical and maternal data, and maternal HBV DNA, HBeAg, anti-hepatitis C virus and anti-hepatitis D virus were also assessed. Ten neonates validated as having HBV intrauterine transmission were selected as cases and others as controls.

RESULTS

The univariate analysis indicated that maternal HBeAg positivity (odds ratio [OR] = 5.96, 95% confidence interval [CI]: 1.61-22.12), HBV DNA positivity (OR = 12.09, 95% CI: 2.97-40.17) and sexual intercourse in the second trimester (OR = 9.15, 95% CI: 1.08-202.99) were significantly associated with an increased risk for HBV intrauterine transmission, whereas contraceptive measures before pregnancy (OR = 0.21, 95%CI: 0.04-0.99) were associated with a decreased risk. The multivariate analysis, however, identified maternal HBV DNA positivity (OR = 19.18, 95%: CI: 3.26-118.73) and sexual intercourse in the second trimester (OR = 1.29, 95%: CI: 1.00-1.66) as the only independent risk factors for HBV intrauterine transmission.

CONCLUSIONS

The risk of HBV intrauterine transmission increased with increased frequency of sexual intercourse. Therefore, it is concluded that maternal HBV DNA positivity and sexual intercourse in the second trimester are independent risk factors for HBV intrauterine transmission.

Polymorphisms of interleukin-1R receptor antagonist genes in patients with chronic hepatitis B in Iran

AIM: To investigate the relationships between polymorphisms of interleukin-1R receptor antagonist genes and susceptibility to chronic hepatitis B in Iran population.

METHODS: Genomic DNA was extracted from the peripheral blood of 80 patients with chronic hepatitis B (57 males, 23 females) aged 12-77 years (mean 36.1 ± 13.8 years) and 147 normal controls (96 males, 51 females) aged 6-75 years (mean 41 ± 18.7 years) who referred to a liver clinic of Tehran and then subjected to polymerase chain reaction (PCR) amplification. PCR products were resolved on a 3% agarose gel and stained with ethidium bromide.

RESULTS: Only three of the five kinds of polymorphism (2/2, 2/4, and 4/4) were found in this study. The frequencies of 2/2, 2/4, and 4/4 were 12.5%, 17.5%, 70% respectively in chronic hepatitis B patients and 6.8%, 24.5%, and 68.7% respectively in controls. IL-1 R allele 2 was detected in 30% of chronic hepatitis B patients and in 31.3% of controls, while IL-1 R allele 4 was detected in 87.5% of chronic hepatitis B patients and in 93.2% of controls. The frequency of IL-1R alleles 2 and 4 was detected in 21.25% and 78.75% of the patients and 19.04% and 80.96% of the controls, respectively.

CONCLUSION: Our results suggest that the carriage of IL-1R receptor antagonist alleles 2, 4, 6 may not play any role in the development of HBV infection. Large population-based studies are needed to investigate the role of IL-1 polymorphisms in the pathogenesis of developing chronic hepatitis B.

IGF2 polymorphisms are associated with hepatitis B virus clearance and hepatocellular carcinoma

The aim of this study was to determine whether IGF2 polymorphisms are associated with the clearance of hepatitis B virus (HBV) infection and the risk of hepatocellular carcinoma (HCC). A total of 1095 Korean subjects were prospectively enrolled in this case-control study. The rates of IGF2 polymorphisms were determined in each group. The IGF2+820G allele (IGF2+820G/G) and the IGF2+6815A/A genotype were strongly associated with the resolution of HBV infection (OR=0.62-0.73; P=0.001-0.03 and OR=0.71; P=0.03, respectively). Haplotype analysis showed that IGF2-haplotype5 (A-C-C-T-A-T-G) and IGF2-haplotype1 (T-C-T-T-A-C-A) were significantly associated with the clearance and persistence of HBV infection (OR=0.55-0.58, P=0.009-0.01 and OR=1.31-1.65, P=0.001-0.007, respectively). On the other hand, the IGF2+2482C/C or +820G/G genotypes were significantly associated with a higher risk of HCC (OR=1.88, 1.68; P=0.04). IGF2 polymorphisms were found to be strongly associated with the clearance of HBV or the occurrence of HCC in patients with chronic HBV infection.

Study of hepatitis B virus gene mutations with enzymatic colorimetry-based DNA microarray

OBJECTIVES

To establish a modified microarray method for detecting HBV gene mutations in the clinic.

DESIGN AND METHODS

Site-specific oligonucleotide probes were immobilized to microarray slides and hybridized to biotin-labeled HBV gene fragments amplified from two-step PCR. Hybridized targets were transferred to nitrocellulose membranes, followed by intensity measurement using BCIP/NBT colorimetry.

RESULTS

HBV genes from 99 Hepatitis B patients and 40 healthy blood donors were analyzed. Mutation frequencies of HBV pre-core/core and basic core promoter (BCP) regions were found to be significantly higher in the patient group (42%, 40% versus 2.5%, 5%, P < 0.01). Compared with a traditional fluorescence method, the colorimetry method exhibited the same level of sensitivity and reproducibility.

CONCLUSIONS

An enzymatic colorimetry-based DNA microarray assay was successfully established to monitor HBV mutations. Pre-core/core and BCP mutations of HBV genes could be major causes of HBV infection in HBeAg-negative patients and could also be relevant to chronicity and aggravation of hepatitis B.

High replicative full-length lamivudine-resistant hepatitis B virus isolated during acute exacerbations

During chronic HBV infections, exacerbations of disease usually occur without clearly understood mechanisms. In this study, full-length HBV genomes were analyzed from four chronic hepatitis B patients who developed resistance to lamivudine [-2'-deoxy-3'-thiacytidine, LMV] accompanied by acute exacerbation of disease. Paired full-length HBV isolates were cloned from the sera of patients prior to LMV treatment and after drug resistant breakthrough isolates emerged with exacerbation. Compared to the isolates before treatment, isolates from all four patients during exacerbation showed marked increase in replicative competence by cell transfection study. Viral genome amplification and direct sequencing was used further to study the sequence differences between the dominant species and the clones used for functional analysis. Apart from mutations at the YMDD motif, no shared mutations were shown between all isolates. The isolates from the one patient who recovered from the exacerbation showed a lower number of mutations, and in particular, lacked basal core promoter (BCP) mutations at 1762/1764. In contrast, BCP mutations were found in isolates from the other three patients. Thus, in patients with acute exacerbation, high replicative strains might be selected from the total HBV quasispecies during treatment, and amongst these strains, those with core promoter mutations were most likely to be associated with severe clinical exacerbations.

Hepatitis B virus: inactive carriers

Inactive carriers forms the largest group in chronic HBV infected patients. Around 300 million people are inactive carriers The inactive HBsAg carrier state is diagnosed by absence of HBeAg and presence of anti-HBe, undetectable or low levels of HBV DNA in PCR-based assays, repeatedly normal ALT levels, and minimal or no necroinflammation, slight fibrosis, or even normal histology on biopsy. Inactive cirrhosis may be present in patients who had active liver disease during the replicative phase of infection. The prognosis of the inactive HBsAg carrier state is usually benign. Long-term follow- up (up to 18 years) of these carriers has indicated that the vast majority show sustained biochemical remission and very low risk of cirrhosis or hepatocellular carcinoma (HCC). Rarely, patients, even noncirrhotics, may develop liver cancer during the inactive HBsAg carrier state. In addition, approximately 20 to 30% of persons in the inactive HBsAg carrier state may undergo spontaneous reactivation of hepatitis B during follow-up. Multiple episodes of reactivation or sustained reactivation can cause progressive hepatic damage and even hepatic decompensation.

Infectious source factors affecting the severity of sexually transmitted acute hepatitis due to hepatitis B virus genotype C

OBJECTIVE

The aim of this study was to identify clinical features and virological aspects of infectious sources that are related to the severity of sexually transmitted acute hepatitis B virus (HBV) infection in patients, especially in cases of genotype C.

METHODS

Nineteen patients with acute HBV infection, 10 classified with severe acute hepatitis (SH) (prothrombin time; PT <40%) and 9 with typical acute hepatitis (AH) (PT >40%), and their infectious sources (all were sexual partners) were studied. Infectious source factors were analyzed in relation to the severity of hepatitis in the patients' partners.

RESULTS

The nucleotide homology of HBV-DNA between each pair was >/=98.9%. Sixteen were infected with HBV genotype C. Among the 16 infectious sources, age, numbers with elevated alanine aminotransferase (ALT, 7/9 vs. 1/7), anti-HBe positivity (8/9 vs. 1/7) and core promoter mutations at nt 1762 (7/9 vs. 1/7), nt 1764 (8/9 vs. 1/7) and precore mutation at nt 1896 (8/9 vs. 1/7) were significantly higher in the sources of SH than in those of AH.

CONCLUSION

Higher age, elevated ALT, anti-HBe positivity and core promoter/precore mutations were possible risk factors for an infectious source of the severe form of sexually transmitted acute hepatitis due to HBV genotype C.

Virological profiles in hepatitis B virus inactive carriers: monthly evaluation in 1-year follow-up study

STUDY SUBJECT: We longitudinally evaluated the virological behaviour and the hepatitis B virus (HBV) genomic variability in inactive HBV surface antigen (HBsAg) chronic carriers.

PATIENTS AND METHODS

Fourteen HBsAg-positive healthy workers (13 inactive carriers and 1 with active HBV infection) were followed up for 12 months by monthly evaluation of aminotransferase, HBV DNA, and IgM anti HBV core antigen (IgM anti-HBc) values. Moreover, HBV serum isolates from each case were amplified, cloned and sequenced to evaluate the presence of the potentially clinical relevant core-promoter and precore mutations. The same technical procedures were used to examine the S gene of isolates from 3 randomly selected inactive carriers and the patients with active HBV infections.

RESULTS

Aminotransferase values were constantly normal in all cases. Viremia levels appear to fluctuate widely over time in each individual case, although the HBV DNA remained below 2 x 10(4) copies/ml in all samples. Only four serum samples from two inactive carriers had IgM anti-HBc values higher than the specific cut-off limit of the assay. Either wild type or core-promoter/precore HBV variants or a mixture of them were detected in the inactive carriers. S gene nucleotide homology among the clones from the three inactive carriers and the subject with active infection was 98.9%, 98.3%, 98.1% and 98.2%, respectively.

CONCLUSIONS

The degree of suppression of HBV replication in inactive carriers is variable over time, and the entity and quality of HBV variability is comparable between active and inactive carriers.

Association of polymorphisms of interleukin-18 gene promoter region with chronic hepatitis B in Chinese Han population

AIM: To investigate the polymorphisms of interleukin-18 (IL-18) gene promoters, and to disclose whether such polymorphisms are associated with susceptibility to chronic hepatitis B in Chinese Han population.

METHODS: Using polymerase chain reaction with sequence specific primers (PCR-SSP) method, the single nucleotide polymorphisms (SNPs) of the promoter region of IL-18 gene at position -607 and -137 were detected in 231 patients with chronic hepatitis B and 300 normal controls.

RESULTS: Allele C at position -607 in the promoter of IL-18 gene was detected in 48.7% of normal controls and 51.9% of patients, while allele A at position -607 was detected in 51.3% of normal controls and 48.1% of patients. The frequencies of -607CC, -607 CA and -607AA genotypes in normal controls were 22.0%, 53.3% and 24.7% respectively and in chronic hepatitis B patients were 26.8%, 50.2% and 23.0% respectively. Allele G at position -137 in the promoter of IL-18 gene was detected in 82.3% of normal controls and 88.5% of chronic hepatitis B patients, while allele C at position -137 was detected in 17.7% of normal controls and 11.5% of patients. The frequencies of -137GG, GC and CC genotype were 67.3%, 30.0% and 2.7% in normal controls respectively, while in chronic hepatitis B patients were 78.8%, 19.5% and 1.7% respectively. The frequency of -137GG genotype in chronic hepatitis B groups was significantly higher than that in normal controls (χ² = 8.55, P = 0.003 <0.05), whereas the frequencies of -607C/-137C and -607A/-137C haplotypes in chronic hepatitis B groups were significantly lower than that in normal controls. The association between genotypes of IL-18 promoter region polymorphisms and HBV copies showed that the frequency of -607AA genotype in high HBV-DNA copies groups was lower than that in low HBV-DNA copies groups (χ² = 6.03, P = 0.014 <0.05).

CONCLUSION: The polymorphisms of the promoter region of IL-18 gene at position -607 and -137 are closely associated with susceptibility to chronic hepatitis B. The people with allele C at position -137 in the promoter of IL-18 gene may be protected against HBV infection; moreover AA genotype at position -607 may be closely linked to inhibit HBV-DNA replication. These findings give some new clues to the study of pathogenesis of chronic hepatitis B.

Polymorphisms of interleukin-1B and interleukin-1 receptor antagonist genes in patients with chronic hepatitis B

AIM: To investigate the relationships between polymorphisms of interleukin-1B (IL-1B) promoter region -511C/T and interleukin-1 receptor antagonist gene (IL-1RN) and susceptibility to chronic hepatitis B in Chinese population.

METHODS: Genomic DNA was extracted from the peripheral blood of 190 patients with chronic hepatitis B and 249 normal controls and then subjected to polymerase chain reaction (PCR) amplification. The PCR products were digested by restriction endonuclease AvaI. The products of digestion were subjected to 20 g/L gel electrophoresis and ethidium bromide staining.

RESULTS: The frequencies of IL-1B (-511) genotypes CC, CT and TT in patients with chronic hepatitis B were 23.7%, 49.5% and 26.8%, while 26.1%, 47.4% and 26.5% respectively in controls. The results showed that there was no significant difference in the frequencies of alleles or genotypes in IL-1B between patients with chronic hepatitis B and controls. The distributions of IL-1B (-511) genotype CC were significantly different between the two subgroups (HBV-DNA ≤ 1×10³ copies/mL as subgroup I, HBV-DNA > 1×10³ copies/mL as subgroup II) of chronic hepatitis B (P = 0.029). Only four of the five kinds of polymorphism (1/1, 1/2, 2/2 and 1/4) were found in this study. The frequencies of IL-1RN genotypes 1/1, 1/2, 2/2 and 1/4 were 88.9%, 9.0%, 0.5% and 1.6% in patients with chronic hepatitis B respectively, while were 81.1%, 16.9%, 0.4% and 1.6% respectively in controls. The frequencies of genotype1/2 and IL-1RN allele 2 in patients with chronic hepatitis B were lower than those in controls (P = 0.016 and P = 0.029, respectively).

CONCLUSION: There is an association between polymorphisms of the promoter region -511C/T of IL-1B and IL-1RN intron 2 and chronic hepatitis B virus infection. Subjects with IL-1RN allele 2 may be resistant to HBV infection, and IL-1B (-511) genotype CC is closely related with HBV-DNA replication, which gives some new clues to the study of pathogenesis of chronic hepatitis B.

Management of hepatitis B in children

Children with hepatitis B infection require management by physicians knowledgeable about the natural history of this disorder and experienced in the treatment of children. Selection of appropriate pediatric patients for treatment will prevent some cases of advanced liver disease later in life. New treatments under development for adults may benefit children as well, once they have been rigorously investigated in the pediatric population. Prevention of new HBV infections is an important part of management in children, and working with public health campaigns will hopefully reduce both vertical and horizontal transmission.

Structural and functional analysis of full-length hepatitis B virus genomes in patients: implications in pathogenesis

The structural analysis, replicative efficiency and immunogenicity of hepatitis B virus (HBV) full-length genomes isolated from different patients or asymptomatic carriers are presented in the present review. Data indicate the importance of viral genome-based studies in elucidating the pathogenesis of HBV infections. Comparison of structural and functional characteristics of viral genomes isolated from various geographical regions might contribute to explaining the differences in HBV clinical manifestation and prognosis in different geographical regions.

Non-sequencing molecular approaches to identify preS2-defective hepatitis B virus variants proved to be associated with severe liver diseases

BACKGROUND/AIMS

PreS2-defective hepatitis B virus (HBV) variants may emerge during chronic HBV infection. These variants carry mutation(s) at the ATG-start-codon and/or in-frame deletion into the preS2 genomic region and are commonly detected by sequencing analyses. We evaluated the prevalence of these variants in a large series of chronic HBV infected patients through non-sequencing molecular approaches.

METHODS

We examined HBV isolates from 110 HBV carriers: 15 were inactive carriers (IC); 50 had chronic hepatitis (CH); 25 were cirrhotics; 19 had hepatocellular carcinoma (HCC). The entire preS2 genomic region was amplified by PCR technique. The amplicons were processed: (A) through electrophoresis on acrylamide gel to reveal deleted genomes; (B) through electrophoresis on agarose gel after digestion by NlaIII enzyme that cuts the wild ATG-start-codon but not the mutated one.

RESULTS

We detected preS2 variants in 56/110 cases (51%). In particular, we found preS2-defective mutants in 2/15 IC, 25/50 CH, 13/26 cirrhotics, and 16/19 HCC. The presence of these variants was thus significantly associated with active infection and liver disease (P<0.002). Moreover, among cases with liver disease preS2-mutants were more prevalent in HCC patients (P<0.02).

CONCLUSIONS

Our non-sequencing molecular methods are sensitive and specific, and simplify the identification of all preS2 HBV variant forms. Infection by these variants is significantly associated with active infection and HCC.

Genetic polymorphisms in IL-10 and IL-12b allele promoter regions in Chinese patients of Han nationality with HBV infection

AIM

To investigate the association of genetic susceptibility to hepatitis B virus infection and disease progression with the allelic polymorphisms of IL-10 and IL-12b promoter regions in Chinese Han population.

METHODS

Two groups of indigenous Chinese subjects (314 subjects in total) were recruited in this study. Group 1 included 104 unrelated patients with chronic hepatitis B virus infection and 76 unrelated healthy donors. Group 2 contained 134 related subjects from seven HBV-infected pedigrees of Han ethnic origin. Total genomic DNA samples were purified from the 1.5 ml of peripheral blood of all participated individuals by using the QIAgen purification DNA kit. Genotyping of IL10-5'A and IL12-5'C alleles was performed by means of PCR-RFLP (restriction fragment length polymorphism) and further proved by direct DNA sequencing. All data were statistically analyzed by using SAS software.

RESULTS

IL10-5'A mutant frequency in unrelated healthy subjects was 41.9% compared with 42.1% in unrelated HBV-infected patients, while IL12-5'C mutant frequency was 64.6% and 55.8% among healthy individuals and HBV-infected patients, respectively. No significant difference was found among the unrelated healthy individuals and unrelated HBV-infected patients. In related individuals from the seven HBV-infected pedigrees, the mutant frequency of IL12-5'C allele was found to be identical to that in unrelated healthy and HBV-infected patients, but the mutant frequency of IL10-5'A allele(19.5%) was significantly different from that(42.0%) in unrelated group (P<0.01).

CONCLUSION

The polymorphisms of IL10-5'A and IL12-5'C allele promoter regions were not correlated with hepatitis B virus infection and disease progression among unrelated subjects, but there was a significantly lower mutant frequency of IL10-5'A allele among related subjects.