血液透析患者输血传播肝相关病毒感染的调查

使用PCR结合微板杂交-ELISA及DNA序列分析技术,分别研究了维持性血液透析患者输血传播性HBV、HCV、HDV、HGV、TTV感染状况,并对HBV、TTV进行基因分型、TTV基因变异状况进行分析.除HDV外,发现血液透析患者中存在多重感染.HBV基因型以C型为主,B型次之.TTV分离株中,G1型为主,G2型次之.TTV基因变异可达39.7%.     

丁型肝炎病毒研究进展

丁型肝炎病毒(HDV)是乙型肝炎病毒(HBV)的卫星病毒,呈世界性流行,其感染和复制与HBV感染存在密不可分的联系。我国是HBV感染的高发国家之一,HBV相关研究较多,但对其卫星病毒HDV的研究较少。我们较全面地梳理了HDV的分子生物学特征、流行病学特点、实验研究模型、检测、预防及治疗几个方面的最新进展,期望对未来HDV的研究起到一定的推动作用。     

PCR—微孔板杂交法检测不同人群TTV DNA

根据报道的TTV全序列设计引物和探针,建立PCR－微孔板杂交法,检测81例正常人群、92例职业献血员123例甲－庚型肝炎、32例非甲－庚型肝炎、48型发性肝癌患者的TTV DNA。结果表明TTV在以上五种人群中的阳性率分别为3．7％、4．3％、21．1％、28．1％、52．0％,前者与后三者比较有显著性差异（P＜0．05）,TTV合并HBV二重感染重叠感染的54．0％,这揭示不同人群均存在TTV感染,正常人群和职业献血员存在健康携带状态,甲－庚型肝炎和非甲－庚肝炎病人为高危人群,TTV可与各型肝炎存在重叠感染,TTV除经血传播外,存在其它传播途径,TTV感染与ALT及TBIL的升高密切相关。     

PCR-微孔板杂交法检测不同人群TTV DNA

根据报道的TTV全序列设计引物和探针,建立PCR-微孔板杂交法,检测81例正常人群、92例职业献血员123例甲～庚型肝炎、32例非甲～庚型肝炎、48例原发性肝癌患者的TTVDNA.结果表明TTV在以上五种人群中的阳性率分别为3.7%、4.3%、21.1%、28.1%、52.0%,前者与后三者比较有显著性差异(P＜0.05),TTV合并HBV二重感染占重叠感染的54.0%.这揭示不同人群均存在TTV感染,正常人群和职业献血员存在健康携带状态,甲～庚型肝炎和非甲～庚肝炎病人为高危人群,TTV可与各型肝炎存在重叠感染,TTV除经血传播外,存在其它传播途径,TTV感染与ALT及TBIL的升高密切相关.     

研发动态

我国首次发现乙肝病毒受体北京生命科学研究所近日发现乙型肝炎(HBV)和丁型肝炎病毒(HDV)的功能性受体,这一发现将有助于深入研究乙肝感染机制,并为感染及相关疾病提供有用的治疗靶点。研究成果在线发表在eLife杂志上。HBV及其卫星病毒HDV必须通     

延边地区丙型肝炎患者合并TT病毒感染的检测

检测丙型肝炎患者血清标本中的TT病毒 (transfusiontransmittedvirus,TTV) ,了解延边地区丙型肝炎患者合并TTV感染状况。采用ELISA检测抗TTVIgG和巢式PCR检测丙型肝炎病毒 (HCV)感染患者血清中TTVDNA。采用全自动生化分析仪检测患者血清谷氨酸氨基转移酶 (ALT)和谷氨酸草酰乙酸氨基转移酶 (AST)。 4 5例丙型肝炎患者抗TTVIgG阳性率为 37.8% (17/45 ) ,巢式PCR阳性率为 4 2 .2 % (19/45 )。延边地区HCV感染患者重叠感染TTV较常见。     

邢台市健康献血员TT病毒感染状况初探

目的：探讨当地健康人群TT病毒(TTV)感染状况及其在人体内长期存在的意义。方法：选择邢台市志愿献血员(120名)进行TTV感染情况检测,利用N22 PCR和UTR PCR两种方法。结果：N22 PCR方法血清中TTV阳性率为30．00％,UTR PCR方法血清中TTV阳性率为100％。结论：说明邢台市区健康人群中存在有TTV感染,并与贵州(6．45％)、深圳(7．80％)等地区报告的TTV DNA阳性率不同。     

新肝炎病毒TTV在各类高危人群中的感染状况和分子流行病学研究

目的观察新肝炎病毒TTV在各类高危人群中的感染状况、基因分型及其在肝病发生和发展过程中的作用。方法在日本株TTVORF1保守区设计了两对套式引物,采用巢式聚合酶链反应扩增血清TTVDNA,并对产物进行分子克隆和部分基因序列分析。结果在非甲-戊型和非庚型肝炎病人、血清HBsAg阳性的肝炎病人、正常献血员、肝炎肝硬化病人、原发性肝癌病人、静脉内吸毒者和女性与男性性乱者中,血清TTVDNA阳性率分别为43.2％(16/37)、28.8％(15/52)、9.3％(4/43)、51.9％(14/27)、38.5％(5/13)、35.0％(14/40)、17.3％(8/45)和18.8％(3/16)。其中非甲-戊型和非庚型肝炎病人、血清HBsAg阳性肝炎病人的ALT平均为(472士276)u·L-1和(385士218)u·L-1;肝炎肝硬化病人TTVDNA阳性率显著高于HBsAg阳性肝炎病人。同时,从非甲-戊型和非庚型肝炎病人、血清HBsAg阳性肝炎病人、正常献血员、静脉内吸毒者和女性性乱者中,分别获得6份TTVDNAORF1克隆,其基因序列与日本株TTVORF1部分基因核苷酸序列同源性为97％～99％,均属于TTV1a型。结论TTV感染和ALT升高存在一定的关系;我国各类高危人群感染TTV以1a型为主,TTV基因型与疾病发生和传播方式关系不大。国内首次报导性传播的TTVDNA基因型。     

阿德福韦酯联合乙肝免疫球蛋白预防HBV 相关性终末期肝病肝移植术 后复发的临床研究

目的:探讨阿德福韦酯(HDV)联合乙肝免疫球蛋白(HBIg)预防HBV相关性终末期肝病患者肝移植术后HBV复发的临床疗效。方法:回顾性分析2005年6月～2009年6月北京市解放军第302医院因HBV相关性终末期肝病接受肝移植的60例患者的临床资料。60例患者根据治疗方法分为治疗组和对照组,治疗组采用HDV联合HBIg预防肝移植术后HBV复发,对照组采用拉米夫定(LAM)联合HBIg预防HBV复发。结果:两组患者随访期内未出现肾毒性表现。治疗组平均随访时间为(21.67±5.37)月,随访期内无复发。对照组平均随访时间为(21.83±6.02)月,随访期内有2例复发。两组术后复发率比较有显著性差异(P<0.05)。结论:HDV联合HBIg预防肝移植术后HBV复发近期疗效优于LAM联合HBIg。     

青海地区献血者HBV感染隐匿风险与基因型分析

目的:探讨青海地区献血者乙型肝炎病毒(hepatitis b virus,HBV)感染隐匿风险与基因型的相关性。方法:采用回顾性研究方法,选择2014年2月-2018年1月在我院进行无偿献血的青海地区人群750例,采用聚合酶链式反应-限制性内切酶片段法(PCR-RFLP)检测HBV DNA基因的多态性,并进行HBV感染隐匿风险分析。结果:在750例人群中,检出HBV隐匿性感染8例,检出率为1.1%,其中窗口期感染3例,一过性感染5例;基因C型6例,基因B型2例,基因B型患者的都为窗口期感染,核酸定量都≤20 IU/m L,与基因C型患者对比差异有统计学意义(P0.05)。多因素Logistic回归分析显示基因C型、核酸定量、家属病史、吸烟为导致HBV隐匿性感染的独立危险因素(P0.05)。结论:青海地区献血者HBV感染隐匿风险相对比较低,多为基因C型,基因C型为导致HBV隐匿性感染的独立危险因素。     

Multiple infection of TT virus (TTV) with different genotypes in Japanese hemophiliacs

To clarify the persistent TT virus (TTV) infection, we studied a possibility of multiple TTV infection by genotype analysis of isolated TTV obtained from seven Japanese hemophiliacs. The nucleotide sequences including 222 bp in the open reading frame 1 (ORF1) region of 10 TTV isolates from each patient were analyzed and classified into various TTV genotypes such as G1 to G6 by phylogenetic analysis using a N-J method. Multiple TTV genotypes were observed in all the hemophiliacs: three different TTV genotypes were found in three patients, whereas four different TTV genotypes were observed in the other three patients. The remaining patient was also infected with TTV of five different genotypes. Moreover, new TTV genotypes were found in these seven patients and tentatively designated as G7. The present findings indicate that multiple TTV infection with different TTV genotypes has occurred in Japanese hemophiliacs. They also provide valuable information to understand persistent TTV infection.     

Hepatitis B surface antigen levels and sequences of natural hepatitis B virus variants influence the assembly and secretion of hepatitis d virus

Various domains of hepatitis B surface antigen (HBsAg) are essential for the assembly and secretion of hepatitis D virus (HDV). This study investigated the influences of the levels and sequences of HBsAg of naturally occurring HBV variants on the assembly and secretion of HDV. Six hepatitis B virus (HBV)-producing plasmids (three genotype B and three genotype C) and six HBsAg expression plasmids that expressed various HBsAg levels were constructed from the sera of HDV-infected patients. These plasmids were cotransfected with six expression plasmids of HDV of genotype 1, 2, or 4 into the Huh-7 hepatoma cell line. Serum HBsAg and HBV DNA levels were correlated with HDV RNA levels and outcomes of chronic hepatitis D (CHD) patients. The secretion of genotype 1, 2, or 4 HDV generally correlated with HBsAg levels but not with HBV genotypes or HBV DNA levels. Swapping and residue mutagenesis experiments of HBsAg-coding sequences revealed that the residue Pro-62 in the cytosolic domain-I affects the assembly and secretion of genotype 2 and 4 HDV and not those of genotype 1. The pre-S2 N-terminal deletion HBV mutant adversely affects secretion of the three HDV genotypes. In patients, serum HDV RNA levels correlated with HBsAg levels but not with HBV DNA levels. Viremia of HDV or HBV correlated with poor outcomes. In conclusion, the assembly and secretion of HDV were influenced by the amounts and sequences of HBsAg. For an effective treatment of CHD, reduction of HBsAg production in addition to the suppression of HBV and HDV replication might be crucial.     

High Endemicity and Low Molecular Diversity of Hepatitis B Virus Infections in Pregnant Women in a Rural District of North Cameroon

Background

A program, supported by the GEMHEP (Groupe d''étude Moléculaire des Hépatites), was established in 2007 in the sanitary district of Tokombéré, to prevent perinatal transmission of hepatitis B virus (HBV). It comprises screening for HBV surface antigen (HBsAg) in all pregnant women and vaccinating the newborn if tests are positive.

Methods/Principal Findings

1276 women were enrolled in the study after providing informed consent. Demographic data and blood samples were available for 1267 of the enrolled patients. HBsAg was determined locally using a rapid test (Vikia HBsAg, Biomerieux). Tests for HBV and HDV virological markers (HBeAg, anti-HDV antibodies (Ab), HBV-DNA, HDV-RNA, HBV and HDV genotypes) were performed on the confirmed HBsAg-positive samples in the virology unit of the Angers University Hospital (France). HBsAg was found in 259 of the 1267 pregnant women (20.4%) between January 2009 and April 2010, of whom 59 were HBeAg-positive (22.7%) with high levels of HBV-DNA. Anti-HDV Ab were found in 19 (7.3%) of the HBsAg-positive women. The prevalence rates of HBsAg and HDV were not age-dependent whereas HBeAg carriers were statistically younger than non carriers. Basal core promoter (BCP) and precore (PC) mutations and genotypes were determined by sequencing. Of 120 amplified sequences, 119 belonged to HBV genotype E (HBV/E) and the 9 HDV strains belonged to HDV clade 1. In the PC region, 83/228 patients (36.4%) harbored a G1896A mutant or mixed phenotype virus. In the BCP region, the double mutation A1762T/G1764A and the G1757A substitution were detected respectively in 26/228 patients (11.4%) and 189/228 patients (82.8%).

Conclusions

Our results confirm the high prevalence and low molecular diversity of HBV in Far Northern Cameroon; more than 20% of the infected women were highly viremic, suggesting a high rate of HBV perinatal transmission and supporting the WHO recommendation to vaccinate at birth against hepatitis B.     

Molecular phylogenetic analyses indicate a wide and ancient radiation of African hepatitis delta virus, suggesting a deltavirus genus of at least seven major clades

Hepatitis D virus (HDV) is a satellite of hepatitis B virus (HBV) for transmission and propagation and infects nearly 20 million people worldwide. The HDV genome is a compact circular single-stranded RNA genome with extensive intramolecular complementarity. Despite its different epidemiological and pathological patterns, the variability and geographical distribution of HDV are limited to three genotypes and two subtypes that have been characterized to date. Phylogenetic reconstructions based on the delta antigen gene and full-length genome sequence data show an extensive and probably ancient radiation of African lineages, suggesting that the genetic variability of HDV is much more complex than was previously thought, with evidence of additional clades. These results relate the geographic distribution of HDV more closely to the genetic variability of its helper HBV.     

病毒性肝炎HAV，HBV，HCV，HDV和HEV重叠感染的研究

采用ＥＬＩＳＡ法检测了１０８例乙型肝炎病毒（ＨＢＶ）感染者血清中的五种肝炎病毒──甲型（ＨＡＶ）、乙型（ＨＢＶ）、丙型（ＨＣＶ）、丁型（ＨＤＶ）和成型（ＨＥＶ）肝炎病毒的标志物,并采用ＰＣＲ技术检测了患者血清ＨＢＶＤＮＡ、ＨＣＶＲＮＡ及ＨＤＶＲＮＡ。结果五种肝炎病毒重叠感染者３５例（３２．４％）,单纯ＨＢＶ感染者７３例（６７．６％）。ＨＢＶ、ＨＡＶＭ重感染率为４．６％,ＨＢＶ、ＨＣＶ二重感染率为９．２％,ＨＢＶ、ＨＤＶＭ重感染率为１４．８％,ＨＢＶ、ＨＥＶ二重感染率为１．９％,ＨＢＶ、ＨＣＶ和ＨＤＶ三重感     

Genetic organization and replication strategy of hepatitis delta virus

Hepatitis delta virus (HDV) is a subviral satellite of human hepatitis B virus (HBV). The discovery in 1977 and subsequent demonstration of HDV as an infectious agent was primarily due to the work of Rizzetto and co-workers. In nature, HDV infections occur only if HBV is present. This is because HDV is a subviral satellite of HBV; HBV provides the envelope, or surface antigens, needed for the assembly of HDV particles. Other than this dependence, HDV seems fundamentally different from HBV; it has a single-stranded RNA genome and replicates via RNA-directed RNA synthesis. Five years ago the first nucleotide sequence of the genome was obtained and as a consequence we have progressively gained a picture of the genetic organization of this unusual agent and of its replication strategy.     

Comparison of diversity of torque teno virus 1 in different mucosal tissues and disorders

Diversity of TTV1 was assessed in the head and neck region in patients with potentially malignant (oral lichen planus, oral leukoplakia) and malignant lesions (oral and laryngeal squamous cell cancers) and was compared to that found in the uterine cervix (cervical atypia and cervical cancer) by directly sequencing the NG061-063 segment of ORF1. These sequences were classified by the formerly used genogroup-genotype system as well as by the newly accepted species classification by aligning with the corresponding region of the type sequences of the 29 TTV species. All sequences obtained during the study clustered together with the TTV1 type sequence; to express diversity within TTV1, genotypes and subtypes of the former classification were used.The commonest subtypes were 2c followed by 2b, 1a and 1b. Subtypes 2b and 2c were evenly distributed among cervical samples; subtype 1a was more frequent in patients with cervical atypia or cancer. Subtypes 2c was more frequent than 2b in head and neck lesions. In conclusion, genotype and even subtype distribution may be important in association with diseases, therefore using this classification for characterization of intraspecies diversity of TTV1 is proposed.     

Prevalence of TT virus in patients with hepatitis B,C and hepatitis of unknown etiology

Discovery of TT virus in 1997 gave raise to intensive subsequent studies to learn about its structure, features and, what is the most important, about its role in pathogenesis of liver disease. The aim of the work was to analyze prevalence of TTV DNA in patients with diagnosed hepatitis B, C, that of unknown etiology and in healthy blood donors as well. Additionally the divergence of TTV sequence was estimated in selected cases. TTV DNA was detected by PCR technique using specific oligonucleotide primers for coding regions. TT virus has been detected in 25.6% (32/125) HBsAg positive patients and in 23.9% (51/213) HCV infected patients. In healthy blood donors the frequency of TTV was 24.3% (34/140) similarly to that found in HCV and HBV infected patients. The frequency of TTV DNA among patients with hepatitis of unknown etiology was 9.1%. This result was statistically significant lower than in the other groups. When detected sequences have been compared to these from NCBI base the homology result was 71% to 95%, and among different patients and groups of patients identity was 46% to 73%. On the basis of the obtained results it can be concluded that it is very unlikely that TTV coinfection plays any significant role in HCV or HBV infection. The hypothetical role of TTV infection in the etiopathogenesis of cryptogenic chronic hepatitis has not been confirmed. The results obtained in the small group of patients with hepatitis of unknown etiology are not conclusive and should be taken with some precaution. The final conclusion is the TTV coinfection does not contribute to the liver pathology. The divergence of TTV sequences may explain the various frequency of TTV viremia reported by other authors.     

Epidemiological,Clinical and Histological Characteristics of HBV/HDV Co-Infection: A Retrospective Cross-Sectional Study in Guangdong,China

Background

The epidemiology of hepatitis D virus (HDV) in China is fairly unknown. The mechanisms whereby HDV leads to accelerated liver disease in hepatitis B virus (HBV)/HDV co-infected patients and the histological characteristics of chronic hepatitis D (CHD) patients need further investigation.

Methods

The prevalence of HDV was retrospectively evaluated in all consecutive hospitalized patients with chronic HBV infection from May 2005 to October 2011. HBV/HDV co-infected patients and HBV mono-infected patients were compared clinically and histologically. Significant histological abnormality was defined as significant necroinflammation (grade ≥A2) and/or significant fibrosis (stage ≥ F2).

Results

6.5% of patients (426/6604) tested positive for IgM anti-HDV. HDV was more common in patients over 50 years old than those under 50 (11.7% vs. 5.1%, P<0.001). HBV/HDV co-infected patients had higher frequencies of end-stage liver disease (ESLD) than HBV mono-infected patients, and HDV co-infection was an independent risk factor for ESLD (OR: 1.428, 95%CI: 1.116–1.827; P = 0.005). The HBV DNA levels in the HBV/HDV group were significantly lower than the HBV group in chronic hepatitis patients (median: 6.50 log₁₀copies/mL vs 6.80 log₁₀copies/mL, P = 0.003), but higher than the HBV group in ESLD patients (median: 5.73 log₁₀copies/mL vs 5.16 log₁₀copies/mL, P<0.001). When stratified by alanine aminotransferase (ALT) level, 46.7%, 56.5% and 80.5% of CHD patients had significant necroinflammation and 86.7%, 87.0% and 90.3% had significant fibrosis with ALT 1–2×upper limit normal (ULN), 2–5×ULN and>5×ULN respectively.

Conclusion

The prevalence of HDV is not low in patients with chronic HBV infection. HDV may contribute to progression to ESLD through late-phase HBV DNA reactivation.