Significance of antibodies to the recombinant E2 protein of hepatitis G virus in haemodialysis patients

Patients on maintenance haemodialysis represent a high-risk group for parenterally transmitted viral infections, such as hepatitis B, C and G. In addition to hepatitis G virus (HGV) (GBV-C) RNA, analysed in previous studies, we characterized the seroprevalence rates of antibodies to the putative E2 protein (anti-E2) of HGV in a German cohort of patients on maintenance dialysis ( n = 72) in comparison to healthy blood donors ( n = 100). The presence of anti-E2 and/or HGV RNA as indicators of present or past HGV infection could be demonstrated in 34.7% of patients and in 16% of the blood donors ( P < 0.01). The infection rates with HGV seem to increase only during the first 6 years of haemodialysis. The simultaneous presence of viraemia and anti-E2 was found very rarely in patients and controls. Therefore, the emergence of anti-E2 indicates clearance of HGV viraemia. In conclusion, patients on haemodialysis are at high risk of acquiring HGV infection, but a chronic carrier state with viraemia is rare. The risk of infection is not strictly correlated with the duration of dialysis.     

Retrospective analysis of non-A-E hepatitis: possible role of hepatitis B and C virus infection

In an effort to determine the cause of non-A-E hepatitis, a retrospective study was undertaken on a group of patients with hepatitis but without serological infection markers of hepatitis viruses A-E. A total of 60 patients admitted to Beijing Ditan Hospital during the period of September 1997 and September 1999 were chosen for this study. These patients were diagnosed as either acute or chronic hepatitis, but no serological markers of hepatitis viruses A-E were detected. Since TT virus (TTV), human parvovirus B19 (B19), SEN virus (SENV), and GB virus C/HGV were reported to be associated with hepatitis, attempts were made to detect the presence of these viruses in the sera of patients with non-A-E hepatitis by a nested polymerase chain reaction (nPCR) method. Also, more sensitive nPCR and RT-nPCR methods were used to determine HBV DNA and HCV RNA in these patients. Results derived from these analyses demonstrate that HBV DNA was detected in most of these patients (47/60, 78.3%), suggesting that HBV infection played a major role in occult non-A-E hepatitis and detection of HBV DNA by more sensitive PCR methods such as nPCR should be considered for diagnosis of HBV infection. In addition, HCV RNA was detected in three (5%) of these patients. However, GBV-C (HGV) RNA was not detected, and TTV, B19, and SENV appear not to be associated with non-A-E hepatitis, as the prevalence rates of these viruses in patients with non-A-E hepatitis were similar to those in patients with viral hepatitis A-E. The results from this study indicate that co-infection of TTV or B19 with HBV did not increase the severity of the disease.     

Chronic hepatitis C infection: influence of the viral load, genotypes, and GBV-C/HGV coinfection on the severity of the disease in a Brazilian population

The distributions of the different genotypes of the hepatitis C virus (HCV) and GBV-C virus (GBV-C/HGV) vary geographically and information worldwide is still incomplete. In particular, there are few data on the distribution of genotypes (and their relationship to the severity of liver disease) in South America. Findings are described in 114 consecutive patients from Northeast Brazil (median age 52 years, range 18-72 years) who had abnormal levels of serum aminotransferases and seropositivity for HCV RNA. The patients were recruited from an outpatient clinic between November 1997 and April 1998. Quantitative HCV RNA and GBV-C/HGV RNA estimations were carried out by double-nested polymerase chain reaction (PCR) using primers from the 5'-untranslated regions (UTRs) of the genomes. HCV genotypes were determined by restriction fragment length polymorphism (RFLP) analysis with 5'-UTR primers and by PCR with type-specific 5'-UTR primers. GBV-C/HGV-RNA genotypes were determined by RFLP with specific 5'-UTR primers and phylogenetic trees were constructed using the Neighbour-Joining and Drawtree programs. Histological features were graded and staged according to international criteria. Of the 114 patients, 35 (30.7%) patients had cirrhosis and 22 (27.8%) had mild, 51 (64.6%) had moderate, and 6 (7.6%) had severe chronic hepatitis. Median HCV viral load was 10(6) genome equivalents per millilitre (range 10(4)-10(9)/ml). Frequencies of genotypes were 5.3% type 1a, 44.7% type 1b, 3.5% type 2, 41.2% type 3, and 5.3% mixed types. GBV-C/HGV-RNA was detected in the sera of 12 (10.5%) patients and was distributed among three phylogenetic groups. There were no significant differences between patients with the predominant HCV genotypes (1b and 3) with respect to gender, age group, viral load, severity of liver disease, or coinfection with GBV-C/HGV.     

Diversity of Hepatitis G Virus within a Single Infected Individual

The extent of population diversity among GB virus C (GBV-C)/hepatitis G virus (HGV) within a persistently infected individual (Iw) was investigated by sequence analysis of multiple clones generated from polymerase chain reaction (PCR)-amplified products of cDNA analogous to fragments of 5 non-coding region (5NC), envelope region 1/2 (E1/E2) and non-structural region 3 (NS3) of viral genome. Although nucleotide substitutions were more common in coding regions than in the 5NC region, there was no region corresponding to the hypervariable region of hepatitis C virus in the E1/E2 region. Transition substitution exceeded transversion by 7 to 12-fold, and 79.4% of substitutions were synonymous. This bias against substitutions producing amino acid replacements and the use of Pfu DNA polymerase with an error rate 10 times lower than the observed frequency of substitution, suggests that most substitutions were not artefactual. This data suggests that individual genomes of HGV within an infected individual may differ from each other at 0.23–0.84% nucleotide position and at 0.42–0.61% amino acid position.     

庚型肝炎病毒感染的致病性与临床意义

为探讨庚型肝炎病毒(HGV)感染的致病性及临床意义,本文从5927例各型肝病人中筛选出抗—HGV阳性的173例病人与抗—HGV阴性的肝炎患者30例(对照组)进行观察比较。结果显示,抗—HGV阳性组与对照组部分血清ALT、BIL水平有显著性差异。173例抗—HGV阳性病人中,单独感染者31例,有70.79％(23/31)的病人迁延不愈,其中死亡2例,而30例对照组中,56.67％(17/30)迁延不愈,无1例死亡,重叠感染组142例有81.69％(116/142)迁延不愈,与对照组相比P<0.01有高度显著性差异,其中死亡3例。提示HGV的感染是病毒性肝炎的病原之一,它能造成各种不同程度的肝损害,在临床上可引起各型肝炎,病情趋于迁延,病死率较高,重叠感染可加重病情。由此可见,HGV具有致病性。HGV的感染在病毒性肝炎中具有重要的临床意义。     

Prevalence of hepatitis G virus RNA in a monocentric population of French haemophiliacs

Hepatitis G virus (HGV) and hepatitis GB virus (GBV-C) have been reported as possible causes of non-A–E transfusional hepatitis. To assess the prevalence of hepatitis G virus infection in haemophiliacs we retrospectively investigated the presence of viral RNA in 92 patients with and without HCV infection. HGV/GBV-C RNA was reverse transcribed and amplified with primers from the 5' non-coding region of the genome. RNA was detected in 16/92 patients (17.4%). Restriction enzyme analysis revealed that the 16 patients belonged to the HGV-like genotype. Serology with E2-specific antibodies demonstrated that HGV viraemia underestimates previous infection by HGV. 33 patients were positive for HGV; all but two have cleared HGV RNA. 47/92 patients had a marker of prior infection by HGV.
No difference between HGV RNA positive and negative patients was observed concerning age, diagnosis, HIV and HCV status. Previous HBV infection correlated with the frequency of HGV infection. There was no difference in alanine aminotransferase levels between HGV positive and negative patients. All 18 patients exposed to only virally inactivated plasma-derived concentrates were negative for both HGV RNA and anti E2 antibodies.
Prior exposure to untreated concentrates correlated with HGV viraemia ( P =0.03), HGV seropositivity ( P =0.0002), and markers of HGV infection ( P <0.0001).
In haemophiliacs with a past exposure to non-inactivated concentrates, persistence of HCV RNA (53/74 patients) was more frequent than HGV RNA persistence (16/74 patients) although HGV viraemia is more frequent than HCV viraemia in blood donors. This may be related to a greater ability of individuals to clear HGV infection and suggests that hepatitis G virus infection in multi-transfused patients has a better outcome than infection with other blood-borne viruses.     

单纯庚型肝炎病毒感染肝组织中糖复合物的表达

研究人单纯庚型肝炎病毒感染肝组织中糖复合物表达的特点，探讨单纯庚型肝炎病毒感染的机理。正常肝组织标本10例为对照组，单纯庚型肝炎病毒感染肝组织22例为观察组。以九种植物凝集素做为I抗，利用印法对两组标本行免疫组化染色，统计两组阳性率，x^2检验差异显著性。对照组肝细胞膜上DSL、PHA—E、DBA、STL等四种凝集素受体呈弱阳性，观察组DBA受体表达增强且出现了PHA—L、UEA—I、ECL三种新的凝集素受体。庚型肝炎病毒感染后肝组织尤其肝细胞表面糖复合物的表达在数量及结构上发生变化，这些变化为探讨其感染机理提供了有益的资料。     

RT-PCR法检测HGV RNA和ELISA法检测抗-HGV意义探讨

目的:探讨检测HGV RNA和抗-HGV的临床意义。方法:采用逆转录聚合酶链反应(RT-PCR)技术和ELISA法分别对351例住院肝炎患者血清中HGV RNA和抗-HGV进行检测。结果:351例中有32例(9.11％)HGV RNA阳性,34例(9.68％)抗HGV阳性,5例(1.41％)两项同时阳性;在11例患者不同住院期间的检测中发现,7例检测结果无变化,1例HGV RNA阴转,1例抗-HGV阴转,2例抗-HGV阳转。结论:HGV RNA和抗-HGV同时阳性的病例比较少。大多数情况两者不是同时存在,诊断意义可能有所差异;HGV RNA阳性表示现症感染,而抗-HGV阳性可能是感染后期或恢复期的标志。在HGV感染过程中会出现HGV RNA阴转或抗-HGV阴转和阳转的可能。     

乙型肝炎患者血清中庚肝病毒核酸的检测

目的:了解乙型肝炎患者HGV感染情况,探讨HGV感染与HBV感染的关系.方法:应用巢氏PCR对1104例乙型肝炎患者进行了血清HGV-RNA检测,以251名正常人为对照.结果:共检出血清HGV-RNA阳性者34例,阳性率3.08%.乙型肝炎患者血清HGV-RNA阳性率(3.17%)与正常人群(2.79%)相比无显著差异(P＞0.05).慢性乙肝患者血清HGV-RNA阳性率(4.78%)显著高于急性乙肝患者(0.96%)(P＜0.05).结论:HGV感染可表现为病毒携带状态、亚临床型和不同临床类型,乙型肝炎患者并不比正常人群更易感染HGV,HGV与HBV重叠感染可能与病情发展和慢性化的形成有关.     

非甲～戊型肝炎病原学研究现状

非甲-戊型病毒性肝炎病原学一直是肝病研究的热点之一，近年来相继报道了GBV、TTV、SENV等新型病毒，并对其病原学、流行病学特点及致病性等进行了相关研究。本文就非甲一戊型肝炎病原学研究现状作一综述。