Basal core promoter, precore region mutations of HBV and their association with e antigen, genotype, and severity of liver disease in patients with chronic hepatitis B in India

Spontaneous mutations of hepatitis B virus (HBV) could influence the severity of liver disease. Since the basal core promoter (BCP) and the precore (Pc) regions are important for viral replication, these regions were examined for naturally occurring mutations and were correlated with the genotype, e antigen status, and severity of liver disease. In 82 patients with histologically confirmed chronic hepatitis B, the BCP and Pc regions were sequenced and aligned with known wild-type sequences. Sequence based HBV genotyping was done and HBV DNA was quantified. Thirty-three (40%) patients had decompensated chronic liver disease and the remaining patients had chronic hepatitis B. Forty-six (56%) patients were HBeAg positive. HBV genotype A was found in 28%, D in 65%, and B/C in 7.3%. The Pc G1896A mutation was more common in HBeAg-negative (33% vs. 2%, P < 0.01) patients and was genotype D specific. The Pc G1862T mutation was detected more often in HBeAg-positive than HBeAg-negative (37% vs. 11%, P < 0.01) patients and was genotype A specific (P < 0.01). BCP mutations at the 1,762/64 nucleotide positions were common in HBeAg negative than positive (36% vs. 13%, P < 0.05) and were equally common in different genotypes. TA 1-3 region mutations of the BCP were significantly higher in HBeAg-negative as compared to HBeAg-positive patients (78% vs. 26%, P < 0.01). BCP mutations had significantly higher HBV DNA levels. It is concluded that Pc G1862T mutant is Genotype A-specific but is not always associated with e antigen. The TA 1-3 rich mutations of BCP region are also associated with the absence of e antigen in Indian patients.     

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. J. Med. Virol. 84: 1177–1185, 2012. © 2012 Wiley Periodicals, Inc.     

Features and clinical implications of hepatitis B virus genotypes and mutations in basal core promoter/precore region in 507 Chinese patients with acute and chronic hepatitis B

BackgroundThe association of hepatitis B virus (HBV) genotypes and basal core promoter (BCP) and precore (PC) mutations with the clinical characteristics is increasingly recognized.ObjectiveTo investigate virologic features and clinical implications of HBV genotypes, BCP and PC mutations between large-size patients with acute hepatitis B (AHB) and chronic hepatitis B (CHB).Study designOne hundred and eighty-two AHB patients and 325 CHB patients were investigated. HBV genotypes and BCP/PC mutations were determined by direct sequencing. Mutations at 10 interested sites of the BCP/PC region were compared between the two groups of patients.ResultsAHB patients had a significantly higher ratio of genotype B to C than CHB patients (37.4–62.6% vs. 16.6–83.4%, P < 0.001). The prevalence of BCP/PC wild-type virus was 60.4% in AHB patients in contrast to 28.9% in CHB patients. Significantly lower prevalence of A1762T, G1764A, G1896A, and G1899A but higher prevalence of T1758C was found in AHB patients. Interestingly, T1758C and A1762T/G1764A appeared mutual restraint. Genotype B virus had lower BCP mutation frequency and similar PC mutation frequency compared to genotype C virus. AHB patients with BCP/PC mutant virus had higher viral load, whereas CHB patients with BCP/PC mutant virus had lower viral load and elevated alanine aminotransferase, in comparison with those with the wild-type virus.ConclusionPatients with genotype B virus, BCP/PC wild-type virus or T1758C mutant virus were more susceptible to develop AHB, whereas high prevalence of the BCP/PC mutations was associated with CHB development.     

Precise analysis of the effect of basal core promoter/precore mutations on the main phenotype of chronic hepatitis B in mouse models

High replication and mutation rates of hepatitis B virus (HBV) often lead to reduced or suppressed hepatitis B e antigen expression. The most common mutations are genomic variations in the basal core promoter (BCP) and pre-core (PC) regions. However, the effect of BCP/PC mutations on HBV phenotype in vivo remains unclear. We compared and analyzed BCP/PC mutations and BCP/PC reverse mutations in mouse models. In addition to terminating the expression of HBeAg, BCP/PC mutations also resulted in a significant decrease in HBsAg, HBV DNA, and cccDNA in the early stage, and an obvious increase in serum alanine aminotransferase throughout the transfection period. In both groups, serum HBV DNA was positively correlated with intracellular HBV DNA and cccDNA. Further, we found that interleukin-4 (IL-4) and L-10 levels were significantly lower in the BCP/PC(M) group than in the BCP/PC(R) group at 4 weeks post-injection. However, IL-1β was significantly lower in the BCP/PC(M) group than in the BCP/PC(R) group at 26 weeks post-injection. In summary, we precisely analyzed the effect of BCP/PC mutations on the phenotype in vivo, which is important to evaluating disease progression and treatment responses of variable chronic hepatitis B patients.     

The correlation between serum HBsAg levels and viral loads depends upon wild‐type and mutated HBV sequences rather than the HBeAg/anti‐HBe status

Despite several studies regarding the correlation between serum HBsAg titers and viral loads, the association remains uncertain. Eighty‐nine individuals were selected randomly from a Chinese cohort of 2,258 subjects infected persistently with hepatitis B virus (HBV) for cross‐sectional and longitudinal analysis. Viral loads of mutant HBV are lower than those of wild type HBV. The serum HBsAg titers correlate positively with viral loads in both HBeAg positive and negative subjects (r = 0.449, P = 0.013; r = 0.300, P = 0.018, respectively). No correlation between serum HBsAg titer and viral loads was found in any of the four phases of chronic HBV infection. The serum HBsAg titers correlate positively with viral loads in the group with wild type sequences of the PreS/S, basal core promoter (BCP), and preC regions of HBV(r = 0.502, P = 0.040). However, the correlation was not seen in the group with mutations in these regions (r = 0.165, P = 0.257). The correlation between HBsAg titers and viral loads was seen in individuals with wild type PreS/S sequences but not in the subgroup with BCP double mutations or PreC stop mutation, although their sequences in the preS/S regions were wild type. All these findings were confirmed by the longitudinal analysis. In conclusion, the correlation between serum HBsAg levels and viral loads may not differ between HBeAg positive and negative individuals but may depend on wild‐type or mutated genomic sequences. Therefore, HBsAg quantitation may be used as a surrogate for viral loads in only wild‐type HBV infections. J. Med. Virol. 87:1351–1360, 2015. © 2015 The Authors. Journal of Medical Virology Published by Wiley Periodicals, Inc.     

HBV PC区和BCP区变异与Peg-IFNα-2b疗效的关系及治疗前后的变化

目的:探讨乙型肝炎病毒(HBV)前核心区(PC区)G1896A和基本核心启动子区(BCP区)A1762T/G1764A突变与聚乙二醇化干扰素α-2b(Peg-IFNα-2b)治疗应答的关系及相关变异在治疗前后的变化。方法:69例HBeAg阳性慢性乙型肝炎(CHB)患者,接受48周Peg-IFNα-2b治疗并随访24周。PCR扩增每位患者第0周和第72周HBV PC和BCP区并测序分析突变情况,同时监测患者第0、4、8、12、24、36、48、60和72周HBsAg、HBeAg、丙氨酸转氨酶(ALT)和HBV的DNA水平。结果:共14例患者检测为野生型(20.29%),55例患者检测为突变型(79.71%)。野生型较突变型HBeAg基线水平更高(P=0.024)。患者基线和72周时野生型、PC突变型、BCP突变型和PC+BCP突变型所占构成比发生明显变化(P=0.004)。野生型、PC突变型、BCP突变型和PC+BCP突变型患者在72周的HBeAg血清转换率和联合应答率差异均无统计学意义。结论:PC区和BCP区突变对HBeAg阳性B/C基因型CHB患者Peg-IFNα-2b治疗应答无明显影响,但治疗前后各突变所占构成比发生明显变化。     

Characterization of hepatitis B virus genome variability in Iranian patients with chronic infection, a nationwide study

Hepatitis B virus (HBV) isolates from Iranian patients around the country were characterized. Eighty-one complete genomes from HBV isolates were sequenced and analyzed. The studied population was grouped into three categories including inactive carriers, patients with chronic hepatitis, and patients with liver cirrhosis. Molecular and phylogenetic analyses revealed that Iranian patients were infected with HBV genotype D and subgenotype D1. The most common subtype was ayw2, followed by ayw3 and ayw4. Several deletions and insertions that had no correlation with disease outcome were observed in the HBV genomes. The most frequent mutation in the major hydrophilic region (MHR) of HBV surface antigen (HBsAg) was sP120S. Almost half of the patients studied carried precore (PC) mutant variants and one-third of the studied population was infected with variants carrying basal core promoter (BCP) mutations. PC and BCP mutations were observed in older patients, especially in those with chronic liver disease. Sixty-seven patients (82.7%) were HBeAg negative, and the prevalence of precore mutant isolates (G1896A) was higher in this group than in HBeAg-positive patients. Lamivudine drug resistance mutations were detected after 1 year of treatment in about 30% of lamivudine-treated patients. In conclusion, these results demonstrate that HBV subgenotype D1 is the only subgenotype circulating in Iran, and there is no evidence of any exotic genotype in the region. The HBV PC (G1896A) mutation may play an important role in the clinical outcome of the disease by increasing the risk of progressive liver disease among Iranian patients infected with HBV.     

Variations in the functional domain of basal core promoter of hepatitis B virus among Eastern Indian patients with prevalence of genotypes A, C, and D among the same ethnic population

Mutations in the basal core promoter (BCP) and precore (PC) regions are associated with persistent and intermittently high hepatitis B virus (HBV) replication in several patients. The variability in the functional domains of BCP and PC region of HBV and their association with disease progression and clinical outcome were assessed in Eastern India, an unique region where three HBV genotypes, A, D, and C are prevalent among the same ethnic group. PCR amplification and direct sequencing of BCP and PC region was done on sera obtained from 130 HBsAg positive subjects with different clinical presentations. Associations of the apparent risk factors with clinical advancement were evaluated by statistical methods including multiple logistic regression analyses (MLR). HBV genotype A was present in 33.08%, C in 25.38%, and D in 41.54% cases. Genotypes A and C were associated with higher rate of T1762/A1764 mutations than the most predominant genotype D. HBeAg negative state was associated with considerably higher rate of C1753 mutation. T1762/A1764 along with C1753 was common among cirrhosis and T1762/A1764 without C1753 was frequent among chronic liver disease cases. No significant association was found between A1896 point mutation and clinical status. Multivariate analysis revealed that T1762/A1764 double mutation, HBV/A, age ≥25 years, C1753 and A1899 were critical factors for clinical advancement while age ≥25 years and C1753 as significant predictor for cirrhosis in comparison with chronic liver disease. In conclusion, the analysis of the BCP variability may help in monitoring the progression towards advanced liver disease in Eastern Indian patients.     

Hepatitis B virus genotype B with G1896A and A1762T/G1764A mutations is associated with hepatitis B related acute-on-chronic liver failure

The existence of statistical associations between hepatitis B‐related acute‐on‐chronic liver failure and both hepatitis B virus (HBV) genotype and mutations in the basal core promoter (BCP) and precore (PC) regions needs to be confirmed. A total of 322 patients with a chronic HBV infection, including 77 with hepatitis B‐related acute‐on‐chronic liver failure, 109 with hepatocellular carcinoma (HCC) and 136 with chronic hepatitis B (CHB) were enrolled. The HBV genotype and the presence of mutations in the BCP/PC regions were determined by direct sequencing, and the frequencies were compared in the three patient groups. Overall, 198/322 (61.5%) were infected with genotype B and 124/322 (38.5%) with genotype C. Genotype B was significantly more frequent in patients with acute‐on‐chronic liver failure than CHB (92.2% vs. 60.3%, P < 0.001). As a contrast, genotype C was more common in patients with HCC than CHB (58.7% vs. 39.7%, P = 0.003). In genotype B patients, the A1762T/G1764A, A1846T, and G1896A mutations were significantly more prevalent in patients with acute‐on‐chronic liver failure than CHB (50.7% vs. 28.0%, P = 0.004; 59.2% vs. 34.1%, P = 0.002; 69.0% vs. 41.5%, P = 0.001, respectively). In multivariate analysis, the risk factors for acute‐on‐chronic liver failure were genotype B, A1762T/G1764A, and G1896A. In conclusion, CHB patients with genotype B, G1896A, and A1762T/G1764A had a higher tendency to develop liver failure than patients with genotype C. Therefore, HBV genotyping and detecting G1896A and A1762T/G1764A mutations might have important clinical implications as predictive risk factors for hepatitis B‐related acute‐on‐chronic liver failure. J. Med. Virol. 83:1544–1550, 2011. © 2011 Wiley‐Liss, Inc.     

Hepatitis B e antigen‐negative mutations in the precore and core promoter regions in Korean patients

Most patients with hepatitis B e antigen (HBeAg)‐negative chronic hepatitis B have variants of the hepatitis B virus (HBV) that include mutations in the precore or core promoter regions of the HBV genome. The aim of this study was to investigate the patterns of precore and core promoter mutations and their relationship to HBeAg expression in Korean patients. Four hundred seventy‐five Korean patients with chronic HBV infection between February 1995 and December 2003 were enrolled in this study. There were 236 HBeAg‐positive and 239 HBeAg‐negative patients. Blood samples were tested for HBsAg, anti‐HBs, HBeAg, hepatitis B e antibody (anti‐HBe), liver function tests, and serum HBV DNA. Mutations in the precore and core promoter regions were determined by direct sequencing. In the core promoter region, the C1740, C1753, T1762/A1764, and T1766 mutations were associated with HBeAg escape (all; P < 0.05). In the precore region, a higher frequency of the C1802, A1828, T1846, A1850, C1858, T1862, and A1896 mutations was found in HBeAg‐negative patients (all; P < 0.05). In particular, the A1896 mutation was associated with high serum levels of ALT and HBV DNA in HBeAg‐negative patients (P = 0.014 and 0.026, respectively). Mutations around the Kozak sequence (nucleotides 1809–1812) were found in 6.7% of patients and were not associated with undetectable HBeAg (P = 0.13). In Korean patients, various mutations in the precore and core promoter regions were associated with HBeAg escape and amelioration of hepatic inflammation in HBeAg‐ negative patients. Only the A1896 mutation contributed to HBeAg‐negative chronic hepatitis B. J. Med. Virol. 81:594–601, 2009 © 2009 Wiley‐Liss, Inc.     

海府地区慢性HBV感染不同免疫状态患者基因分型、病毒变异研究

目的 了解海府地区慢性HBV感染不同免疫状态患者基因分型、病毒变异及其相互之间的关联性.方法 入选对象为海府地区慢性HBV感染患者,依照HBV感染自然史分为4组:慢性无症状HBV携带组、HBeAg(+)CHB组、HBsAg-IaC组、HBeAg(-)CHB组,各50例,PCR-RELP、PCR-反向点杂交法检测所有样本基因型、病毒变异.结果 ①4组患者B基因型感染分布比率分别为:60％、56％、62％、60％;C基因为:38％、38％、34％、32％;D基因为:2％、6％、0、6％;B+C基因为:0、0、4％、2％.各型基因在4组患者中感染同比分布差异无统计学意义(P＞0.05).4组之间优势基因均为B、C基因,尤以B基因感染为主.②4组患者均存在PC、BCP区变异,其中HBeAg(-)CHB组患者变异比例最高,其次为HBeAg(+)CHB组,与HBsAg-IaC组相较,差异有统计学意义(x2=24.73、18.32、6.78、3.84;P=6.59E-07、1.87E-05、0.009、0.049).③B、C型基因感染患者均存在PC、BCP区变异.PC、BCP区变异结果中C基因型发生比例较B基因型高,分别为:43.66％比15.97％、33.80％比10.92％,两者相较差异有统计学意义(x2=17.59、14.84,P=2.74E-05、0.000).结论 海府地区慢性HBV感染优势基因为B、C基因,尤以B基因为主,4种免疫状态均存在PC、BCP区变异.C基因型感染患者及HBeAg(-)CHB患者存在高PC、BCP区变异,可能更易引起严重的肝细胞炎症、坏死和纤维化修复、病毒的高复制及流行,因此,对患者基因分型及病毒变异进行有效监控,将为海府地区慢性HBV感染者的管理开辟新的途径,具有很高的临床实用价值.     

乙肝病毒基因型及病毒变异对慢性肝病进展的影响

目的进一步研究HBV基因型及病毒变异与慢性肝病进展的关系。方法用聚合酶链式反应-限制性片段长度多态性（PCR-RFLP）以及部分PCR产物测序的方法对401例慢性HBV感染者，包括112例HCC患者（HCC组）。129例无症状携带者（ASC组），70例肝硬化患者（LC组）和90例慢性肝炎患者（CH组）进行HBV基因分型以及BCP和PC变异检测。结果401例慢性HBV感染者中181例发生B基因型感染，220例发生C型感染。HCC组中C型分布高于其他3个疾病组；C基因型感染者BCP变异多于B基因型；B基因型感染者PC变异多于C基因型：同时BCP变异发生率随着病程进展而递增：在ASC组、CH组、LC组和HCC组里的BCP变异阳性率分别为22．4％、35．0％、50．0％、74．1％。C1与C2亚型相比，C1有较高BCP变异阳性率，而C2有较高PC变异发生率。结论BCP变异与肝病进程存在依从关系，因此BCP变异的检测对慢性HBV感染的疾病进展和临床结局的评估有重要意义。     

Distribution of hepatitis B virus (HBV) genotypes among HBV carriers in the Cote d'Ivoire: complete genome sequence and phylogenetic relatedness of HBV genotype E

The characteristics of hepatitis B virus (HBV) genotype E are not well known because only a few studies have been carried out by complete genome analysis. The aim of this study was to elucidate the distribution of HBV genotypes in Cote d'Ivoire, and to clarify the genotype-related characteristics of genotype E. The distribution of HBV genotypes among 48 HBV carriers in Cote d'Ivoire was determined using serological and genetic methods. The characteristics of genotype E were evaluated by complete genome sequences, and further investigations of small S gene, basic core promoter (BCP) mutation, and precore mutation were undertaken. HBV genotype distribution among the 48 carriers was 6.3% for genotype A, 6.3% for genotype D, and 87.4% for genotype E. Complete genomes of two genotype E strains were sequenced, and found to have 98.2% to 99.2% homology at the nucleotide level when compared with genotype E strains reported previously. In 24 genotype E carriers, the precore mutation was detected in 75% of the patients without HBeAg, in contrast to only 25% of the patients with HBeAg (P < 0.05). All 24 strains have T at nucleotide 1858 in the precore region. In contrast, BCP double mutation was detected in 17% of the patients with HBeAg, and 33% of the patients without HBeAg. These results indicated as the following: (1) genotypes A, D, and E of HBV exist in Cote d'Ivoire and genotype E is the most prevalent; (2) genotype E spread with low genetic diversity over the complete genome in West Africa; (3) HBV precore and/or BCP double variants were common among the patients with genotype E infections.     

X gene mutations in hepatitis B patients with cirrhosis,with and without hepatocellular carcinoma

Specific mutations in the hepatitis B virus (HBV) genome have been reported to be associated with the development of hepatocellular carcinoma (HCC). The goal of this study was to determine whether mutations in the HBV X gene are associated with the development of HCC in hepatitis B patients with cirrhosis. Forty‐two patients infected with HBV genotype C2 with cirrhosis and HCC were compared with 46 patients with cirrhosis but without HCC. X gene mutations were determined by direct sequencing in all patients. The HCC and non‐HCC groups were similar with respect to clinical characteristics, and the presence of T1762/A1764, T1653, and V1753 mutations was not significantly different between the two groups (P = 0.068, P = 0.097, P = 0.442, respectively). Only the B1499 mutation was associated significantly with HCC (P = 0.015) (odds ratio: 3.42, 95% CI: 1.24–9.48). In hepatitis Be antigen (HBeAg)‐positive patients, advanced age was associated significantly with HCC (P = 0.038), whereas in HBeAg‐negative patients, the B1499 mutation was associated more significantly with HCC (P = 0.01). Patients in the B1499 mutation group exhibited significantly higher AST and ALT levels compared with patients infected the wild‐type virus. In conclusion, B1499 is a novel mutation associated with HCC in Korean patients with cirrhosis infected with HBV genotype C2. J. Med. Virol. 81:1721–1725, 2009. © 2009 Wiley‐Liss, Inc.     

Evolution of precore/core promoter mutations in hepatitis B carriers with hepatitis B e antigen seroreversion

The evolution of precore stop codon mutation (A1896) and dinucleotide mutation (T1762/A1764) in the basic core promoter (BCP) of hepatitis B virus (HBV) genome during transient seroconversion and seroreversion of hepatitis B e antigen (HBeAg) remains unclarified. Five HBeAg-positive HBV carriers who experienced transient seroconversion followed by seroreversion of HBeAg (Group I, 3.3%) and 3 HBeAg-negative HBV carriers with documented reversion of HBeAg (Group II, 2.5%) in a prospective cohort of 272 patients with chronic hepatitis B were thus identified. The sequential changes at the precore nucleotide 1896 and BCP dinucleotide 1762/1764 were determined by polymerase chain reaction and direct sequencing. At enrollement, precore A1896 and BCP T1762/A1764 were noted in 4 (50%) and 1 (13%) of the eight patients. During a median follow-up period of 58 months (range: 31-76 months), 12 episodes of transient HBeAg seroconversion followed by seroreversion were encountered in Group I patients and 3 episodes of HBeAg seroreversion in Group II patients. Accompanying acute exacerbations were found in two-thirds of patients with either HBeAg seroconversion or seroreversion. Overall, precore nucleotide A1896 remained identical in 73% and 83% of the seroconversion and seroreversion events, respectively. BCP dinucleotide T1762/A1764 remained unchanged in 94% and 92% of the seroconversion and seroreversion events, respectively. At the end of follow-up, only one had both precore and BCP mutations. In conclusion, these data suggested that HBeAg seroreversion might be due to the lack of sustained precore and BCP mutations after HBeAg seroconversion. Although uncommon, HBeAg seroreversion can be associated with hepatitis exacerbation.     

Comparison of genotypes C and D of the hepatitis B virus in Japan: a clinical and molecular biological study

The genotype-related differences between genotype C and genotype D of the hepatitis B virus (HBV) remain unknown. The relationship was studied between the HBV genotypes and their clinical features, paying special attention to genotypes C and D. Serum samples from 413 HBV carriers were genotyped using an enzyme immunoassay (EIA) and by restriction fragment length polymorphism. The nucleotide sequences at the basic core promoter (BCP) and precore (PreC) regions were analysed by direct sequencing. The full genome sequences of three HBV genotype D cases were also examined. Almost all carriers with HBV genotype D were asymptomatic carriers (84.2%). Genotype D was not found in patients with liver cirrhosis and hepatocellular carcinoma. In contrast, carriers with genotype C had mainly chronic liver disease (63.2%; P<0.001). The ratio of hepatitis B e antigen (HBeAg)/anti-HBe was significantly higher in genotype C than in genotype D in the young age-matched group (P<0.01). The mutation at BCP (T1762, A1764) was significantly lower in genotype D than in genotype C among HBeAg-negative patients (P<0.05). The HBV full-genome sequences are very similar to certain HBV genotype D sequences from Europe. In conclusion, genotype C was associated with chronic liver disease, whereas genotype D was related to asymptomatic carriers with earlier HBeAg seroconversion. Thus, the outcome of chronic HBV infection may be different in persons infected with HBV genotypes C and D.     

海府地区慢性HBV感染者病毒学特征与P16mRNA改变的研究

目的 探讨海府地区慢性HBV感染者病毒学特征与P16mRNA改变的相互关系.方法 选取2013年1月至2015年12月期间海口市人民医院住院治疗的200例慢性HBV感染者作为研究对象,依照HBV感染自然史分为慢性无症状HBV携带组、HBeAg(+)慢性乙型肝炎组、非活动性HBsAg携带组和HBeAg(-)慢性乙型肝炎组,各50例.PCR-RELP法检测HBV基因型和PC/BCP变异,RT-PCR检测P16mRNA.比较各个慢性HBV感染不同免疫状态组HBV基因型的分布情况;比较各个慢性HBV感染不同免疫状态组HBV变异类型的比率;比较各个慢性HBV感染不同免疫状态组的P16mRNA表达缺失率;对BCP变异比率与P16mRNA表达缺失率进行相关性分析.结果 (1)各个慢性HBV感染不同免疫状态组HBV基因型的分布情况均以B型为主(P＞0.05),无统计学意义.(2)随着慢性HBV感染自然史的进展,BCP变异的比率却逐渐增高(30.00％ vs61.65％ vs76.47％ vs89.47％)(P＜0.05),差异具有统计学意义.(3)随着慢性HBV感染自然史的进展,各个慢性HBV感染不同免疫状态组P16mRNA的表达缺失率逐步增高(2.00％ vs14.00％ vs26.00％ vs34.00％)(P＜0.05),差异具有统计学意义.(4) Person相关性分析显示,BCP变异比率与P16mRNA表达缺失率呈正相关(r=0.826,P＜0.05).结论 海府地区慢性HBV感染进程的4个阶段(免疫耐受期、免疫清除期、免疫不全期和再活动期)均以B型基因为主,但是随着慢性HBV感染自然史的进展,BCP变异比率和P1 6mRNA表达缺失率均逐渐增高,表明BCP变异和P16基因的改变可能是肝细胞癌进程中的重要事件.     

Hepatitis B virus genotypes and lamivudine resistance mutations in HIV/hepatitis B virus-coinfected patients

BACKGROUND: Differences in subtypes, hepatitis B early antigen (HBeAg)-negative variants, and drug resistance mutations all seem to influence the clinical and therapeutic outcome in patients with chronic hepatitis B virus (HBV) infection. Information available on the prevalence and distribution of distinct HBV variants in HIV-positive patients is scarce. METHODS: All HIV-infected patients with persistent serum hepatitis B surface antigen and detectable HBV viremia were identified in a reference HIV clinic located in Madrid, Spain. HBV load, subtypes, precore (PC) and basal core promoter (BCP) variants, and lamivudine (LAM) resistance mutations were analyzed. RESULTS: A total of 81 HBV/HIV-coinfected patients (4.1%) were identified in a population of 1968 HIV-positive patients. Plasma specimens with detectable HBV viremia could be obtained from 62 subjects, and this was the study population that underwent further virologic characterization. HBV genotype distribution was as follows: A (n = 27), D (n = 27), E (n = 1), F (n = 2), and G (n = 3). Two patients had mixed HBV genotypes (A/E and A/F). HBV subtype A was predominant (74%) among patients infected through sexual contact, whereas HBV-D was most frequent (74%) among intravenous drug users (P < 0.001). PC/BCP mutants were more frequent in patients with HBV-D than in those with HBV-A (63% vs. 18%; P < 0.01). Median time on LAM was 40 months; patients with HBV-A tended to show LAM resistance mutations more often (53% vs. 44%) and to develop them earlier (35 vs. 45 months) than patients with HBV-D. The dual L180M + M204V/I mutant was the predominant resistance pattern, although a triple rt173V + 180M + 204V, which acts as a vaccine escape mutant, was found in 1 individual. In the multivariate analysis, patients with LAM resistance mutations were significantly more frequently HBeAg-positive and older than individuals with wild-type HBV. Hepatitis-delta was recognized in 13 (21%) of these 62 HBV viremic patients, with no association with specific HBV variants. CONCLUSION: Risk transmission group, age, and positive serum HBeAg are the main determinants of distinct HBV virologic variants, including HBV genotypes and LAM-resistant mutants, in HBV/HIV-coinfected patients.     

Molecular epidemiological study of hepatitis B virus infection in two different ethnic populations from the Solomon Islands

The Solomon Islands is a multi-ethnic nation with a high rate of hepatitis B virus (HBV) infection. The prevalence relative to ethnicity was examined in relation to HBV infection, genotypes, and mutations. Asymptomatic populations (n = 564, 308 Melanesian and 118 Micronesian) from the Western Province were enrolled. Positive samples for Hepatitis B surface antigen (HBsAg) were examined for serological status, genotyping, viral load, and mutations of the basic core promoter (BCP) and pre-core (Pre-C) regions. The positive rate for HBsAg was 21.5%. The major Melanesian genotype was C (HBV/C), whereas the major Micronesian genotype was D (HBV/D). The prevalence of Hepatitis B e antigen (HBeAg) in serum was lower in carriers of HBV/D than of HBV/C. While the prevalence of the BCP mutation (T(1762)A(1764)) tended to be higher in HBV/C, that of the Pre-C mutation (T(1846)) was significantly higher in HBV/D (P < 0.0001). Genetic distance and phylogenetic analyses based on complete genome sequences were also carried out for two strains of HBV/C and two strains of HBV/D, and the findings were compared with those in the DDBJ/EMBL/GenBank database. The full-length sequence revealed that strains from the Solomon Islands were classified into subgenotype C3 (HBV/C3) and D4 (HBV/D4), and that the HBV/D strains were related closely to those from Papua New Guinea. HBV infection in the Solomon Islands is hyperendemic, and the genotype is ethnicity-specific. HBeAg appears to clear from the serum in young adulthood in HBV/D infection, which may be influenced by genotype-dependent features in relation to viral mutations.