丙型肝炎病毒血清学分型与基因分型研究

为了解某农村单采浆供血员人群所感染丙型肝炎病毒（ＨＣＶ）的血清型和基因型构成，并对两种分型方法进行比较，本工作以ＨＣＶＣ区型特异性多肽对抗－ＨＣＶ进行血清学分型，对已确定血清型的血清进行５′非编码区（ＮＣＲ）逆转录套式聚合酶链反应（ＲＴ－ｎＰＣＲ）和限制性片段长度多态性（ＲＦＬＰ）分析以确定基因型，并对６份扩增产物进行序列测定。结果显示１４０份抗－ＨＣＶ阳性血清中，血清Ⅰ型和Ⅱ型分别为４４份（３１．４３％）和１２份（８．５７％），余８４份未能分型。４４株已知血清型的ＨＣＶ中，１ｂ、２ａ和３ｂ等３种基因型分别为３４株（７７．２７％）、９株（２０．４５％）和１株（２．２７％）。两种分型方法一致率为９３．１８％（４１／４４）。对６株ＨＣＶ５′ＮＣＲ的序列分析证实了ＲＦＬＰ分型的正确性。结论认为该人群ＨＣＶ感染以血清Ⅰ型或基因１ｂ型为主；Ｃ区型特异性多肽血清学分型法与ＲＦＬＰ基因分型法符合率高，具有一定应用价值。     

沈阳地区各型丙型肝炎患者丙型肝炎病毒的基因分型

目的研究沈阳地区丙型肝炎病毒（ＨＣＶ）基因型分布状况及其临床意义。方法应用聚合酶链反应（ＰＣＲ）方法对沈阳地区８４例血清抗－ＨＣＶ及ＨＣＶＲＮＡ均阳性的各临床型丙型肝炎患者进行ＨＣＶ基因分型。结果８４例丙型肝炎中,ＨＣＶ－Ⅱ型４５例（５３．６％）,ＨＣＶ－Ⅲ型２６例（３０．９％）,Ⅱ／Ⅲ混合型１３例（１５．５％）;ＨＣＶ不同基因型在各型丙型肝炎中总体分布不一致,经统计学处理,Ｐ＜０．０５;在急性肝炎、慢性肝炎轻度、中度、重度及肝炎后肝硬化中,ＨＣＶ－Ⅱ型感染分别占５５．６％,３６．２％,７５．０％,８５．７％及８８．９％;ＨＣＶ－Ⅲ型感染分别占２２．２％,４６．８％,８．３％,０％骸１１．１％。结论沈阳地区ＨＣＶ感染以Ⅱ型为主,其次为Ⅲ型及Ⅱ／Ⅲ混合型;ＨＣＶ基因型与丙型肝炎严重程度密切相关。     

重组干扰素对慢性丙型肝炎抗病毒疗效5年随访观察

目的观察重组干扰素α－２ａ，α－２ｂ抗丙型肝炎病毒（ＨＣＶ）的近、远期疗效。方法重组干扰素α－２ａ治疗组７０例，重组干扰素α－２ｂ４６例对照组２８例，治疗后随访５年。结果治疗结束时，ＨＣＶＲＮＡ阴转率和血清ＡＬＴ复常率α－２ａ组分别为６７１４％和７０００％，α－２ｂ组分别为６９５６％和７１７３％，随访５年后，α－２ａ组ＨＣＶＲＮＡ阴转率和血清ＡＬＴ复常率分别为３５７１％和４７１４％，α－２ｂ组分别为３９１３％和５２１７％，均显著高于对照组（Ｐ＜００１和Ｐ＜００５）。基因分型以ＨＣＶⅠ组感染为主（７５８６％），干扰素对ＨＣＶⅡ组感染的疗效优于ＨＣＶⅠ组。结论重组干扰素α－２ａ与α－２ｂ均为有效的抗丙型肝炎病毒药物，慢性丙型肝炎患者干扰素治疗的早期疗效较好。ＨＣＶ基因型有预测干扰素疗效的意义     

丙型肝炎病毒基因分型及其与干扰素治疗应答的关系

目的为了解山西省丙型肝炎病毒的基因型和基因型对干扰素疗效的预示价值。方法用ＨＣＶ５’ＮＣ区酶切分型方法对９４例丙型肝炎病人进行基因分型，并观察其中４５例患者对干扰素α１ｂ治疗的应答。结果显示ＨＣＶⅠ组（Ⅰ、Ⅱ型）感染８０例（８５１％），ＨＣＶⅡ组（Ⅲ、Ⅳ型）感染１２例（１２８％），ＨＣＶⅠ／Ⅱ组混合感染２例（２１％）。在接受干扰素治疗的病例中，ＨＣＶⅠ组感染（３５例）的应答率为３７１％，持续应答率为１７１％，而Ⅱ组感染（１０例）的应答率为８０％，持续应答率为６０％，两组相比，有显著性差异（Ｐ＜００５，Ｐ＜００２５）。结论表明山西省以ＨＣＶⅠ组感染为主，干扰素对ＨＣＶⅡ组感染的疗效优于ＨＣＶⅠ组感染，ＨＣＶ基因型有预测干扰素疗效的意义。     

丙型肝炎病毒基因分型及其与疾病程度、感染途径和干扰素疗效的关系

为探讨广州地区丙型肝炎病毒（ＨＣＶ）感染的基因型及其与疾病程度、感染途径和干扰素疗效的关系，作者应用分型ＰＣＲ技术对１５６例抗－ＨＣＶ阳性患者血清ＨＣＶＲＮＡ进行分型检测，并分析不同程度肝病及不同感染途径ＨＣＶ基因型分布，且对５１例经干扰素治疗的慢性丙肝作分型评价。结果１２４例ＨＣＶＲＮＡ阳性中，Ⅱ型占９０．３％（１１２例），Ⅲ型占８．１％（１０例），Ⅱ／Ⅲ型混合感染占１．６％（２例），未检出Ⅰ、Ⅳ型，说明广州地区ＨＣＶ感染以Ⅱ型为主；不同程度肝病及不同感染途径之间ＨＣＶ基因型构成比无明显差异，表明基因型与疾病严重程度及感染途径关系不大；干扰素治疗病例，ＨＣＶ－Ⅱ、Ⅲ型感染的总应答数、完全应答数及部分应答数分别为１８／４１，１１／４１，７／４１和８／１０，６／１０，２／１０，提示Ⅲ型感染疗效较好，ＨＣＶ基因型似可作为选择干扰素治疗病例及判断疗效的参考指标，但是由于观察的Ⅲ型病例数较少，需积累更多的资料才能作出更客观的结论。     

慢性丙型肝炎患者HCV基因型调查

目的 研究丙型肝炎病毒（ＨＣＶ）基因型的流行病学特点。方法 采用ＩＮＮＯ－ＬＩＰＡ反向线形探针杂交法，对来自我国南方（上海，武汉，徐州）、北方（北京、天津）和东北（大连、沈阳）７市的１０７例慢性丙型肝炎患者进行了ＨＣＶ基因型调查。结果（１）地域性，ＨＣＶ１ｂ是主要的基因型，其检出率达８３．１７％，其中东北２市（７２．２２％）低于北方２市（８７．６５％，Ｐ〈０．０１）；２型的检出率较低，仅占６．８６     

对中国人群中Ⅲ／2a型HCV高变区1序列变异规律的横？…

目的 研究中国丙型肝炎患者Ⅲ／２ａ型丙型肝炎病毒（ＨＣＶ）包膜蛋白Ｅ２／ＮＳ１高变区１（ＨＶＲ１）序列变异的规律及意义。方法 应用逆转录巢式ＰＣＲ技术,从３８例Ⅲ／２ａ型ＨＣＶ感染患者血清中,扩增ＨＣＶ部分包膜区基因片断（ｎｔ１４０～１５８２,ＨＣＶ－Ｊ６）,纯化后直接采用双脱氧链末端终止法进行序列分析。结果 本组Ⅲ／２ａ型ＨＣＶ ＨＶＲ１位于氨基酸（ａａ）３８４～４０８位,与有关文献报道的结果（     

合肥地区输血后慢性肝炎HCV基因分型研究

目的：探讨合肥地区输血后慢性肝炎ＨＣＶ感染的基因型。方法：用逆转录聚合酶链反应（ＲＴＰＣＲ）检测ＨＣＶＲＮＡ,对ＨＣＶＲＮＡ阳性标本用型特异引物ＰＣＲ进行ＨＣＶ分型。结果：６３ 例患者中检出ＨＣＶ　ＲＮＡ５４ 例,阳性率为８５．７％ ;其中Ⅱ型４６ 例（８５．２％）,Ⅲ型６ 例（１１．１％）,Ⅱ／Ⅲ型２ 例（３．７％）。结论：提示合肥地区ＨＣＶ感染大多数属Ⅱ型。     

从四例丙肝患者系列血清标本分析HCV基因的变异

目的 研究丙型肝炎病人系列血清标本的丙型肝炎病毒（ＨＣＶ）基因型变化及ＨＣＶ膜区基因变异和“准种”现象。方法 对４例因献血感染ＨＣＶ病人的系列血标本，用特异性引物ＰＣＲ扩增检测，５’－ＮＣＲ和核心区测序确定ＨＣＶ基因莳工对标本膜区基因进行克隆重，每个标本随机选择５～９个克隆进行测序分析。结果 发现随着时间推移，存在ＨＣＶ基因型的转换现象。在２种ＨＣＶ基因型转换期存在混合感染。所有测定序列均为１ｂ或     

20例中国人HCVⅡ/1b型高变区1序列变异的动态观察

目的 动态研究中国人群ＨＣＶⅡ／１ｂ型包膜蛋白Ｅ２／ＮＳ１高变区１（ＨＶＲ１）序列变异规律、意义及影响因素。方法 应用逆转录巢式ＰＣＲ技术从２０例ＨＣＶⅡ／１ｂ型感染的中国病人血清中扩增了ＨＣＶ部分包膜区基因片段（ｎｔ１４４９～１５８６，ＨＣＶ－Ｊ），纯化后直接采用双脱氧链末端终止法进行序列分析。结果 中国人群ＨＣＶ ＨＶＲ１位于氨基酸（ＡＡ）３８４～４１０位，有６个较保守的ＡＡ位点；３８５位Ｔｈ     

Molecular epidemiology of hepatitis C virus infection amongst intravenous drug users in rural communities

The prevalence of hepatitis C virus (HCV) infection amongst a group of intravenous drug users (IVDUs) resident in West Suffolk (East Anglia, England) was investigated and compared with the prevalence of infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV). In addition, both the level of HCV persistence, as defined by detection of viral RNA, and the HCV genotypes present in this population were determined. It was found that HCV antibodies were present in 59% of those tested; by comparison 22% had antibodies to HBV and 1% antibodies to HIV. HCV RNA was found in 44% of those with HCV antibody. HCV genotype 1 was the most prevalent within this population although both genotypes 2 and 3 were also represented. © 1995 Wiley-Liss, Inc.     

Hepatitis C virus genotypes in different regions of the former Soviet Union (Russia,Belarus, Moldova,and Uzbekistan)

The prevalence of HCV genotypes in four republics of the former Soviet Union (Russia, Belarus, Moldova, and Uzbekistan) was investigated. Overall, 197 HCV isolates from 66 blood donors and 131 patients with chronic hepatitis were typed. Viral sequences from sera of infected subjects were amplified by nested RT-PCR using primers from the core region and typed by one or two techniques: (1) DNA enzyme immunoassay (DEIA) and (2) PCR with a set of type-specific primers. Only three major HCV genotypes were identified in this study population. HCV 1b was found to be the predominant virus type both among blood donors and chronic hepatitis patients, followed by 3a, 2a, and 1a (chronic hepatitis patients: 1b-82%; 3a-10%; 2a-4%, 1a-5% and 2c-1%; blood donors: 1b-77%; 3a-17%; and 2a-6%). No significant difference in genotype distribution was observed between different countries or between blood donors and chronic hepatitis patients within the same country. Results of the genotyping procedures were confirmed by direct sequencing of 216 nt PCR fragments corresponding to part of HCV core gene. Phylogenetic analysis of HCV 1b sequences from this study and from the Genbank demonstrated that the sequences from the former Soviet Union do not form evolutionary lineage(s) different from those of strains of the same subtype circulating in other geographical regions. J. Med. Virol. 53:36–40, 1997. © 1997 Wiley-Liss, Inc.     

Molecular epidemiology of hepatitis B, C and D viruses in Turkish patients

Summary. Different genotypes of the hepatitis viruses may influence the clinical outcome of the disease. The distribution of genotypes may vary according to geographical regions. The aim of this study was to evaluate hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) genotypes in Turkish patients with chronic hepatitis in a large cohort of patients. Genotyping was performed in 41, 59 and 365 patients with chronic hepatitis B, D and C, respectively, and 36 hemodialysis patients with chronic hepatitis C. Genotypes were determined by direct sequencing in hepatitis B and by polymerase chain reaction-restriction fragment length polymorphism in hepatitis C and D patients. In addition, HBV subtyping by multiplex PCR and subtype specific ELISA were performed in 83 and 71 HBsAg (+) blood donors, respectively. All hepatitis B (100%) and hepatitis D (100%) patients had genotype D and type I, respectively. HBsAg subtyping by two methods yielded that 99% of the patients were subtype ayw. S gene amino acid sequence in the 41 patients included for HBV genotyping revealed the ayw2 subtype. Genotype distribution of 365 patients with chronic C hepatitis were as follows: 306 (84%) patients genotype 1b, 43 (11%) patients genotype 1a, 10 (3%) patients genotype 2, 3 (1%) patients genotype 3, 3 (1%) patients genotype 4. Among 36 patients receiving hemodialysis, 28 (78%) patients had genotype 1b and 8 (22%) patients had genotype 1a. The study indicates that Turkish patients with chronic viral hepatitis show very little genotypic heterogeneity. Subtype ayw and the genotype D of HBV DNA, and the type I of HDV RNA represent almost 100% of related infections. The genotype 1b of HCV RNA was found to be significantly dominant in Turkish patients.     

Markers of hepatitis C and B virus infections among blood donors in Ho Chi Minh City and Hanoi, Vietnam.

Blood donors in two cities in Vietnam were tested for markers of hepatitis C virus (HCV) and hepatitis B virus infections. Antibody to HCV was detected by passive hemagglutination with antigens of the second generation in 101 (20.6%) of 491 donors in Ho Chi Minh City; it was detected less frequently (P < 0.001) in donors in hanoi (4 [0.8%] of 499). HCV RNA was tested for in donors with antibody by PCR with nested primers from the 5'-noncoding region and detected in 79 donors in Ho Chi Minh City and 4 donors in Hanoi. HCV RNA was genotyped by PCR with type-specific primers from the core gene. Of 83 HCV carriers from Vietnam, 24 (29%) were infected with HCV of genotype I/1a 19 (23%) were infected with II/1b, 4 (5%) were infected with III/2a, and 2 (2%) were infected with mixed genotypes (I/1a and II/1b); HCV genotypes in the remaining 34 (41%) donors, including all 4 donors in Hanoi, were not classifiable into I/1a, II/2a, IV/2b, or V/3a. Of the 10 isolates with unclassifiable genotypes, 2 showed substantial sequence divergence within the 5'-noncoding region from reported isolates with known genotypes (I/1a to 6a). An analysis of part of the core gene sequence indicated that six of the remaining isolates most likely represented new HCV genotypes. Hepatitis B surface antigen and the corresponding antibody, respectively, were detected in 15 (3.1%) and 234 (47.7%) donors in Ho Chi Minh City as well as 15 (3.0%) and 248 (49.7%) donors in Hanoi. These results indicate an extensive spread of HCV among Ho Chi Minh City donors and HCV of novel genotypes in vietnam.     

Genotype distribution and comparison of the putative envelope region of hepatitis C virus from Korean patients

Comparative nucleotide sequence studies of the genomes of hepatitis C virus (HCV) revealed that there are at least 6 different genotypes of HCV. The prevalence of HCV genotypes among the patients with liver diseases in Korea was investigated using the polymerase chain reaction (PCR) for the NS5 region. In the 75 HCV RNA positive samples, two genotypes, type 1b and type 2a, were the major causative agents which accounted for 60% and 33% of infections respectively, while 7% could not be assigned a genotype by the methods used. The nucleotide sequences of cDNAs encoding the putative envelope proteins from 10 type 1b and 5 type 2a genotype samples were analyzed. Approximately 31–42% of the nucleotide sequences of type 1b samples examined differed from those of different genotypes, In the case of type 2a samples, 36–42% of the nucleotide sequences differed from those of different genotypes. The diversities of the amino acid sequences were the same or greater than those of the nucleotide sequences. Two hypervariable regions (HVR1 and HVR2) were recognized in both HCV genomes of genotypes 1b and 2a. However, the sequence divergence within the HVR2 region of genotype 2a was less than that of genotype 1b. © 1995 Wiley-Liss, Inc.     

Molecular epidemiology of TT virus in Italy and phylogenesis of viral isolates from subjects at different risk for parenteral exposure

The prevalence and genotype distribution of human TT virus (TTV) in Italy were analysed in 593 subjects at different risk of parenteral infection who included blood donors, patients with chronic type C hepatitis (HCV), thalassemic patients, patients on haemodialysis, human immunodeficiency virus type 1 (HIV-1)-negative intravenous drug users (IVDUs), and HIV-1-infected subjects (IVDUs, heterosexual contacts and homosexual males). Plasma TTV-DNA was detected using nested PCR with primers deduced from the N22 region of the open reading frame 1 (ORF-1) and from the untranslated region (UTR) of the viral genome. Phylogenetic analysis of the sequences obtained from ORF-1 was also undertaken. A high prevalence of plasma TTV-DNA was observed using the UTR primers, with rates varying from 83-100% in the study groups. Using the N22 primers, HIV-1 positive IVDUs and homosexual males, haemodialysed patients and thalassemic patients had a significantly higher TTV prevalence (range: 23.0-86.1%) than blood donors, who displayed a high frequency of positivity (10.6%). Sequence analysis of 127 N22-positive isolates revealed that 42.5% were of type 1, 53.5% of type 2, 2.4% of type 3, and that two isolates (1.6%) were closely related to genotypes 1-2 but distinct from the other major genotypes. TTV-2 was significantly more prevalent in patients at high risk for parenteral infection and in HIV-1 positive homosexuals. In sequential samples from 15 TTV-infected subjects, N22 sequences were detectable persistently in 12 (80.0%) and UTR sequences persisted in all 15 patients over a mean period of 29.6 months. This data indicates that TTV is widespread in Italy in parenterally exposed subjects, and that the infection frequently persists.     

Hepatitis C virus genotype distribution among intravenous drug user and the general population in Hong Kong

This study describes the distribution of hepatitis C genotypes among 106 intravenous drug users and 949 non-drug users in Hong Kong. Genotypes were identified by multiplex RT-PCR targeting the core region of viral genome. The accuracy of this typing system in identifying genotypes 1b and 6a was assessed by phylogenetic analysis. The distribution of hepatitis C virus (HCV) genotypes amongst non-drug users was 63.6% for genotype 1b, 23.6% for 6a, 4.5% for 1a, 3.9% for 3a, and 3.1% for 2a; whereas amongst the intravenous drug users, it was 58.5% for genotype 6a, 33.0% for 1b, 5.7% for 3a, 0.9% for 1a, and 0.9% for 2a. The proportion of genotype 6a was significantly higher (P < 0.001), whereas that for genotype 1b was significantly lower (P = 0.001) for the intravenous drug user group. Multivariate analysis revealed significant independent associations for the distribution of HCV genotypes 1b and 6a with age, sex, and intravenous drug user status. The co-circulation of a common (1b) and a rare (6a) HCV genotype in Hong Kong provides a unique opportunity for future studies to compare their transmission efficiency, clinical course, and response to treatment.