合肥地区献血员庚型肝炎病毒的分子生物学研究

目的了解台肥地区献血员的庚型肝炎病毒(GBV—C／HGV)感染情况。方法应用酶免疫测定法(EIA)和逆转录一套式多聚酶链反应法(RT—PCR)分别检测献血员中的抗-GBV-C/HGV和GBV-C/HGV RNA。结果 献血员中抗-GBV—C/HGV检出率为1．7％(18／1 050)．抗-GBV—C／HGV阳性血清中GBV／HGV RNA占66.7％(12/18)；男性和低年龄组献血员抗-GBV—C／HGV阳性率分别低于女性和高年龄组．两差异有显性(P<0.05)；抗-GBV—C／HGV阴性的献血员有6名转为阳性，2名抗-GBV-C/HGV和GBV-C／HGV RNA阳性的献血员有1名转为阴性。结论GBV—C／HGV在合肥地区献血员中有较高的感染率；献血员中存在着GBV-C／HGV阳性但ALT正常的献血员，应尽快对献血员进行GBV-C／HGV感染指标的检测。     

HGV／GBV—C与HCV混合感染者肝组织中相关病毒表达的 …

了解ＨＧＶ／ＧＢＶ－Ｃ与ＨＣＶ混合感染者肝组织中ＨＧＶ／ＧＢＶ－Ｃ相关抗原的分布状况,探讨ＨＧＶ－ＧＢＶ－Ｃ对肝脏的损害机制,方法以抗ＨＧＶ／ＧＢＶ－Ｃ ＮＳ５单克隆抗体或抗ＨＣＶ ＮＳ３单克隆抗体为试剂,采用免疫组织化学方法检测肝炎病人肝组织中ＨＧＶ／ＧＶ、ＨＣＶ相关抗原表达。     

庚型肝炎病毒在老年乙型肝炎中的表达

目的：了解庚型肝炎病毒（hepatitis G virus,HGV）在老年乙型肝炎患者中感染状况。方法：使用基因重组的抗-HGV NS5单克隆抗体，采用链霉菌抗生物素蛋白-过氧化酶方法，对36例老年乙型肝炎肝穿活检组织进行HGV抗原检测。结果：检出率为8.3%，显示病毒抗原在肝组织中的分布和免疫表达特点。结论：在老年乙型肝炎患者这一特殊人群中，HGV的重叠感染比HGV的单一感染有其更广泛的意义。     

法国HCV RNA阳性供血者GBV-C/HGV标志物:HCV基因型和危险因素相关性分析

背景 通过反转录多聚酶链反应检测RNA或检测包膜蛋白E2抗体可以监测到OC型GB病毒/庚型肝炎病毒GBV-C/HGV感染。研究设计和方法 研究的目标是了解感染HCV的供血人群中HBV-C/HGV标志物感染阳性者的比例,及与HCV基因型和危险因素相关的GBV-C/HGV传播途径。结果 在306例HCV RNA阳性供血者中,GBV-C/HGV RNA阳性     

输血传播庚型肝炎的研究进展

HGV/GBV-C是近年发现的新型肝炎病毒,能够引起非甲-非戊型肝炎,HGV/GBV-C广泛存在于输血后肝炎及献血员中。目前实验室检测HGV/GBV-C感染主要依靠RT-PCR和ELISA。本文就RT-PCR及ELISA检测HGV/GBV-C的实验条件和HGV/GBV-C在供血员中的感染情况及其引起输血后HGV/GBV-C感染率进行介绍,并根据目前文献提出了今后献血传播HGV/GBV-C的研究方向。     

献血者血清中HCV NS3和核心蛋白抗原的检测及临床意义

丙型肝炎病毒(HCV)主要经血液传播, 目前尚无预防疫苗,阻断其传播的主要手段为用抗-HCV试剂检测筛查献血者血及血液制品.然而,抗-HCV-IgG阳性并不能判断献血者或病人是否携带HCV,抗-HCV 抗体阴性者体内仍有可能带有HCV,所以输血后丙型肝炎仍有一定的发生率.笔者利用基因工程表达的HCV NS3蛋白及核心蛋白免疫小鼠所制备的单克隆抗体,建立了检测HCVNS3和核心蛋白的ELISA法,旨在更好地判断献血者和病人的HCV携带情况,减少输血后肝炎的发生.     

献血员庚型肝炎病毒感染的研究进展

自1989年确认丙型肝炎病毒(HCV)与戊型肝炎病毒(HEV)以来，仍有少部分肝炎患不能用现有实验室诊断方法分型，提示可能存在着新型肝炎病毒。1995年，美国的Simmons和Linnen等学率先应用分子生物学技术发现一种新型肝炎病毒—庚型肝炎病毒(GBV-C／HGV)。各国学也相继建立了多种GBV-C／HGV血清标本的实验室检测方法．并运用到病毒性肝炎的临床诊断和流行病学研究中去，并取得重要进展。     

抗GOR抗体的检测及其与HCV感染和自身免疫性疾病的相关性

目的：建立抗GOR－IgM类抗体的ELISA检测方法,研究分析抗GOR－IgG和抗GOR－IgM抗体与HCV感染和自身免疫性疾病的相关性。方法：人工合成的并与兔血清蛋白（RSA）交联的GOR肽包被反应板,建立了检测抗GOR－IgM类抗体的间接ELISA。对70例HCV感染者、30例丙型肝炎患者、30例丙型肝炎患者、124例各类自身免性疾病患者进行了抗GOR－IgG和抗GOR－IgM抗体的检测,同时检测抗核抗体、类风湿因子、抗ds-DNA抗体、抗Sm抗体、抗RNP抗体、抗心磷脂抗体和ENA多肽抗体。分析抗GOR－IgG、抗GOR－IgM与HCV感染、HCV基因型、HGV感染和自身免疫性疾病的相关性。结果：1）HCV感染者中抗GOR－IgG阳性率为47．1％（33／70）,抗GOR－IgM阳性率为32．9％（23／70）;抗GOR－IgG和抗GOR－IgM总阳性率62．9％（44／70）;2）Ⅱ型与Ⅲ型两种基因型HCV感染者的抗GOR抗体检出率分别为73．1％（19／26）和66．7％（2／3）,无显著性差异（P＞0．05,x^2检验）。3）自身免疫性疾病患者抗GOR－IgG阳性率为21．0％（26／124）,抗GOR－IgM阳性率为4．0％（5／124）;抗GOR－IgG和抗GOR－IgM同时阳性者有3例。在29例抗GOR阳性患者中,有1例检出抗HCV－IgG。4）在健康人对照组中抗GOR－IgG和抗GOR－IgM检出率分别为3．1％（2／64）和1．6％（1／64）。HCV感染才和自身免疫疾病患者的抗GOR－IgG检出率与正常人相比均有显著性差异（P＜0．05）;HCV感染者的抗GOR－IgM检出率与健康人相比有显著性差异（P＜0．05）,而自身免疫病患者与健康人相比均无显著差异。5）6例HGV感染患者中有1例抗GOR－IgG、抗GOR－IgM均为阳性,阳性率均为16．7％（1／6）。结论：1）HCV感染者（抗HCV－IgG阳性）中,抗GOR－IgG和抗GOR－IgM的阳性率显著高于健康人,抗GOR－IgG与抗GOR－IgM联合检测可提高抗GOR抗体作为HCV感染血清标志物的意义。2）HCV基因型与GOR抗体的出现无关。3）有部分自身免疫病患者体内可出现抗GOR抗体。4）抗GOR抗体与其他自身抗体常不同时存在于同一患者体内,提示产生GOR抗体的机制与其他自身抗体产生的机制不所不同。5）抗GOR－IgG和抗GOR－IgM同时阳性者提示可能与早期HCV或HCV感染有关。     

肝移植受体病肝组织中丙型肝炎病毒的检出及其临床意义

目的：检测成人肝移植受体丙型肝炎病毒(HCV)感染状态，探讨监测肝移植受体术后丙型肝炎复发的意义。方法：收集本移植中心器官移植受体摘除肝脏标本52例，采用Tordji-22和NS32种单克隆抗体进行免疫组织化学检测。结果：所有病例术前血清抗HCV检测均阴性。52例肝移植受体肝脏组织中20例(38．46％)肝细胞内有不同程度的HCV抗原存在。上述2种单克隆抗体的灵敏度及阳性表达方式略有不同，Tordji-22以肝细胞核表达为主，NS3以肝细胞胞质细颗粒状阳性为主。原发性肝癌肝移植组中HCV阳性细胞主要为癌旁肝细胞，少数癌细胞胞质也呈弱阳性。结论：在接受肝移植的慢性终末期肝病或原发性肝癌患者中，有相当病例受体肝脏有HCV感染。由于肝移植后应用大剂量皮质激素及免疫抑制药物可促进HCV病毒在移植肝的肝细胞内复制，导致丙型肝炎复发，明确肝移植受体肝脏HCV感染状态，对肝移植后病情监测、制定治疗方案具有指导意义。     

“健康”职业献血员中丙肝病毒和庚肝病毒RNA的检测

为了解本地区“健康”职业献血员中丙肝病毒(HCV)、庚肝病毒(HGV)的感染现状和探讨献血员筛选HGV的价值。采用逆转录一套式聚合酶链反应法(RT—nPCR)对44例“健康”职业献血员的血浆进行了HCV—RNA和HGV—RNA的检测，同时采用酶免疫法(EIA)进行了抗—HCV和抗—HGV的检测。结果表明，HCV—RNA阳性检出率6．82％(3／44)，抗—HCV均阴性；HGV—RNA阳性检出率2．27％(1／44)。抗—HGV阳性检出率4．55％(2／44)。1例HGV—RNA阳性者，抗—HGV阴性；2例抗—HGV阳性者，HGV—RNA均阴性。提示职业献血员中存在抗—HCV阴性的HCV携带；HGV感染较HCV少见，献血员中是否应用抗—HGV进行筛选还需进一步研究。     

GB virus C/hepatitis G virus infection in Indian blood donors and high-risk groups.

The hepatitis G virus (HGV) or GB virus C (GBV-C) was discovered in 1995 as a putative agent of post-transfusion, non-A-E hepatitis. The present study was carried out with the aim to find the prevalence of this virus among various subject groups at risk for parenteral transmission as well as in healthy control subjects both individually and along with other parenterally transmitted hepatitis viruses. Of the 402 subjects tested, 6.22% were positive for the HBsAg surface antigen, 7.21% were positive for HCV RNA while only 2.24% were seen to be carriers of the HGV/GBV-C RNA. All the HGV/GBV-C positive cases were either multi-transfused thalassaemic subjects or hemodialysis patients. None of the healthy control subjects showed presence of the virus. Seven of the HGV/GBV-C positive subjects showed co-infection with one or more additional virological markers. Also, of the 9 HGV/GBV-C positive subjects, 5 showed elevated ALT levels while 4 showed elevated alkaline phosphatase levels. Overall our findings seem to indicate that HGV infections generally are asymptomatic, transient and self-limiting and the virus does not seem to show a very high prevalence among the Indian population.     

Detection of GB virus C/hepatitis G virus RNA by reverse-transcription polymerase chain reaction.

Recently, a novel RNA virus, designated GB virus C or hepatitis G virus (GBV-C/HGV) has been identified which may possibly be associated with human hepatitis. In this study, the nucleotide sequences of the partial nonstructural 5 (NS5) gene of GBV-C/HGV derived from sera of eight Chinese patients were determined. The overall degree of nucleotide conservation and the existence of regional highly conserved sequences make this part of the genome suitable for the development of diagnostic reagents. On the basis of sequence analysis, two sets of oligonucleotide primers were designed to establish a nested polymerase chain reaction (PCR) for detection of GBV-C/HGV RNA. The efficacy of three PCR methods (first, one stage PCR, second, nested PCR with primers from the NS5 region designed according to the prototype sequence and the third, our newly developed PCR) was compared in 133 Chinese patients with liver disease. The positive rates of these three methods were 8.3%, 11.3% and 18.0% respectively. The specificity of our PCR detecting system was verified by sequencing and restriction fragment length polymorphism (RFLP). In conclusion, because of the heterogeneity and geographic distribution character of GBV-C/HGV, it is necessary to assess the sequence variation among Chinese patients infected with GBV-C/HGV. This may allow to identify GBV-C/HGV RNA with high sensitivity and specificity.     

Persistent infection mechanism of GB virus C/hepatitis G virus differs from that of hepatitis C virus

OBJECTIVE: Changes in the deduced amino acid sequence of the envelope 2 (E2) region of the GB virus C/hepatitis G virus (GBV-C/HGV) were analyzed to investigate whether or not the region contributes to persistent infection with the virus. METHODS: Eight patients with acute hepatitis C and 1 patient with acute hepatitis of unknown etiology were included in the study. GBV-C/HGV RNA was detected in 6 patients, including the patient with hepatitis of unknown origin. The nucleotide sequence of the E2 region of hepatitis C virus (HCV) and GBV-C/HGV was determined by direct sequencing of polymerase chain reaction products in 5 patients with HCV infection and in 6 patients with GBV-C/HGV infection twice during the period of early infection and several months or years later in each patient. RESULTS: The mean substitution rate of the deduced amino acid sequence in the E2 region was over 100 times lower (p < 0.001) in GBV-C/HGV (0.01 +/- 0.04/month/100 sites) than in HCV (2.4 +/- 1.7/month/100 sites). The amino acid sequence of the loop domain of GBV-C/HGV-E2 did not change in any of the 6 patients. On the other hand, the sequence of the hypervariable region of HCV-E2 changed remarkably (5.9 +/- 4.3/month/100 sites). No amino acid substitution in the loop domain was observed in 7 additional patients who showed persistent GBV-C/HGV viremia for more than 2 years. CONCLUSION: These results indicate that changes in the amino acid sequence of the E2 region are not involved in the mechanism of persistent GBV-C/HGV infection.     

Prevalence of hepatitis G in patients on chronic hemodialysis

Hepatitis G virus (HGV) is a newly described RNA virus from the family of flaviviridae. It is closely related to the hepatitis C Virus (HCV) but is more common than HCV among healthy blood donors. The pathogenicity of HGV in immunosuppressed patients such as those undergoing hemodialysis is unclear. We measured the incidence of HGV in 105 patients undergoing hemodialysis in a chronic outpatient hemodialysis facility. HGV-RNA was detected using a RT-PCR method with primers directed against the 5' non-coding region and the NS5a gene of HGV. Nine (8.6%) patients were HGV RNA positive, eleven (10.5%) were anti-HCV positive, three (2.9%) were positive for hepatitis B surface antigen. Four patients were positive for both HGV and HCV; three of them had normal liver enzymes while one showed elevated ALT levels but no other signs of exacerbation of preexisting hepatitis. The prevalence of HGV among dialysis patients is comparable to that of HCV. The transmission route for HCV is nosocomial transmission during dialysis, whereas HGV shows both ways of transmission: blood transfusion mediated by a high prevalence of HGV among healthy blood donors and nosocomial transmission. HGV appears to play a minor role in acute hepatitis, even in immunosuppressed patients.     

Hepatitis C virus and GBV-C/hepatitis G virus in Argentine patients with porphyria cutanea tarda

To investigate hepatitis C virus (HCV) and GBV-C/hepatitis G virus (HGV) genotype prevalence among HCV-infected porphyria cutanea tarda (PCT) patients, 19 HCV-infected patients with associated PCT were studied. A control group of 53 age-matched HCV-infected patients without associated PCT was selected. Eighteen of the 19 serologically positive HCV-PCT patients showed HCV RNA in serum. Genotype 1b was the most prevalent among both HCV-PCT patients (72.2%; 13/18) and age-matched HCV controls (50.9%; 27/53). Such different genotypic prevalence failed to reach statistical significance (chi(2) with Yates' correction, p = 0.19). The single HCV-PCT patient without detectable HCV RNA was also infected with genogroup 3 GBV-C/HGV. This GBV-C/HGV RNA prevalence (5.3%) among HCV-PCT patients is not statistically different from that observed among Argentine blood donors (5.5%; 11/200). To our knowledge, these results show for the first time the molecular epidemiology of both HCV and GBV-C/HGV associated to PCT in America.     

Hepatitis C virus and GB virus C/hepatitis G virus viremia in Swedish blood donors with different alanine aminotransferase levels

BACKGROUND: Hepatitis C virus (HCV) is a known blood-borne hepatotropic virus for which antibody screening of blood donors is universally practiced. The newly identified GB virus C (GBV-C) and its strain variant hepatitis G virus (HGV) are of unknown pathogenic significance, and screening of blood donors for this agent has not yet been implemented. Polymerase chain reaction (PCR) is the most sensitive method for detecting HCV viremia and is the only method presently available for the diagnosis of GBV-C/HGV infection. STUDY DESIGN AND METHODS: RNA extracts of sera from 577 anti-HCV-negative blood donors (393 with elevated alanine aminotransferase [ALT] levels, 184 with normal ALT levels) were tested with nested PCR for HCV and GBV-C/HGV directed at the 5'-noncoding regions of the two viruses. RESULTS: One donor with elevated ALT was HCV PCR positive. This donor was anti-HCV negative when recruited to the study but subsequently developed anti- HCV. Of the 19 donors with GBV-C/HGV viremia in the series as a whole, 16 belonged to the group with elevated ALT levels and 3 to the group with normal ALT levels; the group difference in prevalence was nonsignificant (4.1% [16/393] vs. 1.6% [3/184; p = 0.20]). Phylogenetic analysis showed 16 of the GBV-C/HGV isolates to be classifiable as subtype 2a and three as subtype 2b. At follow-up 3 to 5 years later, 11 of 18 donors were still viremic. CONCLUSION: There was no significant difference in GBV-C/HGV viremia in the group with elevated ALT levels and the group with normal ALT levels. The frequency and subtype distribution in the present series were similar to those in other Western countries.     

Review of the epidemiology, molecular characterization and tropism of the hepatitis G virus/GBV-C

The hepatitis G virus and GBV-C are recently discovered variants of the same virus belonging to the family Flaviviridae (HGV/GBV-C). Although initially thought to be a hepatitis virus, it has been shown to have no association with liver disease. This paper reviews the data relating to the discovery, global prevalence, natural history, disease association, molecular features, replication and tissue tropism of HGV/GBV-C.     

Prevalence of GB virus type C/hepatitis G virus RNA and of anti-E2 in individuals at high or low risk for blood-borne or sexually transmitted viruses: evidence of sexual and parenteral transmission

BACKGROUND: The first epidemiologic evidence of GB virus type C (GBV- C)/hepatitis G virus (HGV) infection showed a high prevalence of asymptomatic carriers in blood donors and in populations at risk for blood-borne viruses. However, by using only viral RNA polymerase chain reaction, those studies underestimated the true spread of GBV-C/HGV infection. The combined detection of GBV-C/HGV RNA and of anti-E2 (which reflects recovery from infection) is necessary to define accurately the prevalence of GBV-C/HGV. STUDY DESIGN AND METHODS: The presence of both anti-E2 and GBV-C/HGV RNA was searched for in 1438 serum samples collected from various groups of individuals at low or high risk for blood-borne or sexually transmitted viruses (blood donors, organ donors, unselected pregnant women, immunocompetent or immunodepressed multiply transfused patients, HIV-positive or HIV- negative homosexual men, intravenous drug addicts). RESULTS: The presence of GBV-C/HGV RNA and/or anti-E2 (exposure to GBV-C/HGV) was frequent in populations at risk for blood-borne or sexually transmitted viruses. GBV-C/HGV appeared also to be sexually transmitted, with transmission from male to female more efficient than vice versa. A particularly elevated level of exposure to GBV-C/HGV was observed in homosexual men. In immunocompetent individuals, the prevalence of anti- E2 was about twice that of GBV-C/HGV RNA, which suggests the frequency of recovery from GBV-C/HGV infection. Most of the GBV-C/HGV RNA- positive individuals had no biochemical evidence of liver damage. CONCLUSIONS: GBV-C/HGV is frequent in populations at risk for blood- borne or sexually transmitted viruses. GBV-C/HGV is not a hepatitis virus, and it seems appropriate to rename it.