Protracted alanine aminotransferase levels in tamarins infected with hepatitis A virus

Eighteen red-bellied tamarins (Saguinus labiatus), experimentally infected with hepatitis A virus (HAV), were followed for up to 1.5 years after initial challenge. Half of these animals developed protracted alanine aminotransferase (ALT) abnormalities, which lasted for between 23 and 55 weeks post-challenge. IgM anti-HAV was detected intermittently during the early phase of their relapsing hepatitis and never after return of ALT levels to normal. The possibility that these findings may be related to continued HAV replication, coinfection with another agent, or the result of an autoimmune phenomenon triggered by HAV are discussed.     

丙型肝炎病毒感染者中抗病毒IgM检测的意义

建立了抗ＨＣＶＩｇＭ间接ＥＬＩＳＡ方法，并用之检测ＨＣＶ不同感染人群。抗ＨＣＶＩｇＭ在不同感染人群中的检出率变化很大。急性输血后丙型肝炎患者检出率可高达９３．８％，而正常献血员中可低至０．６８％。比较抗ＨＣＶＩｇＭ和抗ＬｇＧ阳性中ＨＣＶＲＮＡ的检测结果发现，抗ＩｇＭ阳性者中，不同ＨＣＶ感染人群的ＨＣＶＲＮＡ检出率很高（９３．０％～１００％）；而ＩｇＧ阳性者中ＨＣＶＲＮＡ的检出率变化很大（３７．５％～９３．８％）。在４３例血液透析者中抗ＩｇＭ与ＨＣＶＲＮＡ检测的一致性为８３．７％；抗ＩｇＭ与抗ＩｇＧ检测的一致性为８８．４％，结果提示：（１）抗ＨＣＶＩｇＭ与ＨＣＶ活跃复制有关，（２）抗ＨＣＶＩｇＭ与抗ＨＣＶＩｇＧ检出不完全一致。因此，临床检测抗ＨＣＶＩｇＭ有其特殊意义。     

Optimal time for repeating the IgM anti-hepatitis A virus antibody test in acute hepatitis A patients with a negative initial test

Background/Aims

The nonspecific clinical presentation of acute hepatitis A (AHA) mandates the detection of anti-hepatitis A virus IgM antibodies (IgM anti-HAV) in the serum for obtaining a definitive diagnosis. However, IgM anti-HAV might not be present during the early phase of the disease. The aim of this study was to determine the optimal time for repeating the IgM anti-HAV test (HAV test) in AHA patients with a negative initial test.

Methods

In total, 261 patients hospitalized with AHA were enrolled for this retrospective study. AHA was diagnosed when the test for IgM anti-HAV was positive and the serum alanine aminotransferase (ALT) level was ≥400 IU/L. Repeat HAV test was conducted after 1-2 weeks if the initial HAV test was negative but AHA was still clinically suspected.

Results

The results of the initial HAV test were negative in 28 (10.7%) patients. The intervals from symptom onset to the initial-HAV-test day and from the peak-ALT day to the initial-HAV-test day were significantly shorter in the negative-initial-HAV-test group, but on multivariate analysis only the latter was significantly associated with negative results for the initial HAV test (β=-0.978; odds ratio [95% confidence interval]=0.376 [0.189-0.747]; P=0.005). The HAV test was positive in all patients when it was performed at least 2 days after the peak-ALT day.

Conclusions

The results of HAV tests were significantly associated with the interval from the peak-ALT day to the HAV-test day. The optimal time for repeating the HAV test in clinically suspicious AHA patients with a negative initial HAV test appears to be at least 2 days after the peak-ALT day.     

甲型肝炎患者血清特异性IgM、IgA及总抗体动态变化与临床意义

对６０例甲型肝炎患者血清抗甲型肝炎病毒（ＨＡＶ）ＩｇＭ、ＩｇＡ及总抗体从发病起进行了１年动态观测，并以病程、病情不同分组观察分析。发现病程、病情不同患者抗－ＨＡＶ－ＩｇＡ滴度变化不同，病程长、病情重者，该抗体下降缓慢，持续阳性时间稍长。     

Viral hepatitis A and B in hemodialysed patients

Summary In 113 hemodialysed patients, 167 hospitalized patients, and 143 outpatients the frequency of HAV and HBV markers were studied by testing HBsAg, anti-HBs, anti-HBc, HBeAg, anti-HBe, and anti-HAV. The hemodialysis patients in a dialysiscenter had significantly more often HBV markers (85.7%) than those maintained on home-dialysis (46.5%). 29.9% of the hospitalized patients and 32.1% of the outpatients had HBV markers. By the anti-HBc test up to 41% of additional HBV infections could be detected. — The prevalence of anti-HAV was very high in all groups. Significant differences between the hemodialysis patients and the control groups existed only in the age groups up to 39 years. — The frequencies of HAV and HBV markers were related to age, duration of dialysis treatment, transfusional frequency, and transaminases. The HBV appeared as the clinically important hepatitis agent in dialysis.     

Cyclic excretion of hepatitis A virus in experimentally infected chimpanzees: biophysical characterization of the associated HAV particles.

Experimental infection of two chimpanzees with the Phoenix Antigen strain of HAV resulted in the cyclic excretion of virus particles on days 9-11, 14-15, and 20-21 postinoculation. Isopycnic banding in CsCl of stool suspensions prepared from 9-11; 14-15; and 17, 19, 21 dav stool pools revealed multiple buoyant densities for the associated HAV particles. Hollow HAV particles found in the 9-11 day pool banded primarily at a buoyant density of 1.30 g/cm3. HAV in the 14-15 day stool banded bimodally in a CsCl gradient, with antigen peaks at buoyant densities of 1.29 and 1.33 g/cm3. HAV in the days 17, 19, 21 stool pool also banded bimodally in a CsCl gradient; however, the antigen peaks occurred at buoyant densities of 1.33 and 1.40 g/cm3.     

长春地区儿童甲型肝炎自然感染率的调查

目的为了了解长春地区儿童甲型肝炎自然感染情况。方法采用竞争性抑制ELISA法检测甲型肝炎抗体。结果对417名儿童进行甲肝抗体检测，甲肝病毒抗体-IgG阳性176例，自然感染率为42.21％，学龄前儿童与学龄后儿童自然感染率分别为36．47％和63．64％，统计学分析差异显著，表明甲型肝炎的自然感染率学龄后儿童甲型肝炎的易感率较高。结论0-6岁儿童抗体水平较低，随着年龄的增长，甲肝抗体阳性率呈现上升趋势。     

A nationwide seroprevalence of total antibody to hepatitis A virus from 2005 to 2009: age and area-adjusted prevalence rates

Background/Aims

Recent outbreak of hepatitis A in Korea is clearly related to the epidemiological shift of hepatitis A virus (HAV). However, nationwide seroprevalence data have been limited. This study estimated the nationwide, age- and area-adjusted anti-HAV prevalence from 2005 to 2009.

Methods

Retrospective analysis of the results of total anti-HAV test in 25,140 cases which were requested by 1,699 medical institutions throughout the nation to Seoul Clinical Laboratory from Jan. 1 2005 to Dec. 31 2009 was performed. The estimated seroprevalence was adjusted by area and age of the standard population based on the 2005 Census data from Korea National Statistical Office.

Results

The area-adjusted anti-HAV prevalence in the children younger than 10 years were 33.4% in 2005 and 69.9% in 2009. The most susceptible age groups to HAV infection during the last 5 years were teenagers and the young adults in their age of twenties. The area-adjusted seroprevalence in 2009 were 11.9% in the age group of 20-29 years, 23.4% in the age group of 10-19 years, 48.4% in the age group of 30-39 years. The population in 40-49 years showed geographically different seroprevalence with the lowest rate in Seoul (80%).

Conclusions

The most susceptible age group to HAV infection is 10-29 years, while the young children less than 10 years showed about 70% seropositivity. The changing seroepidemiology should be monitored continuously for the proper vaccination and patient care.     

Detection of hepatitis B virus DNA in serum and relation with the IgM class anti-HBc titers in hepatitis B virus infection

Sera from four groups of patients wtih different serologic markers of HBV infection were examined for HBV DNA using molecular hybridization technique and for IgM class anti-HBc using an ELISA based on the antibody capture principle. Results of HBV DNA assay were generally in good agreement with the presence of HBeAg. However, HBV DNA was found in 13% of anti-HBe+ sera and in one patient with anti-HBc as a sole marker. IgM anti-HBc was detected at high titers in acute hepatitis B patients and was also present during the "window-period." This marker was also found, though less frequently when other markers for HBV infectivity were absent, in chronic hepatitis B patients and healthy carriers. From these findings we conclude that the HBV DNA assay provides a reliable method of detecting the infectious agent, particularly in anti-HBe+ sera and sera with anti-HBc as a sole marker. The assay for IgM anti-HBc is useful for establishing the diagnosis of recent infection in patient with anti-HBc as a sole marker, and during acute hepatitis with very high aminotransferase values, a condition in which HBV DNA may be undetectable.     

呼吸道疾病患儿血液中EB病毒IgM抗体及病毒DNA感染的临床分析

目的 分析呼吸道疾病患儿血液中EB病毒IgM抗体(EBV-IgM)及病毒DNA(EBV-DNA)感染情况.方法 对2013年3月至2016年3月我院收治的呼吸道疾病患儿578例的临床资料进行统计分析.结果 578例患儿中,28例患儿血清EBV-IgM阳性,176例患儿EBV-DNA阳性,阳性率分别为4.8％和30.4％.患儿的血清EBV-IgM阳性率显著低于EBV-DNA阳性率(P＜0.05);男性和女性患儿的血清EBV-IgM和EBV-DNA感染率之间的差异均不显著(P＞0.05);年龄为3-6岁患儿的血清EBV-IgM和EBV-DNA感染率均显著高于其它年龄组(P ＜0.05);1-3月份患儿的血清EBV-IgM和EBV-DNA感染率均显著高于其它时间段(P＜0.05).结论 呼吸道疾病患儿血液中EBV-IgM比EBV-DNA感染率低,二者感染率受到患儿年龄及季节影响,与性别无关.     

Incidence and seroprevalence of hepatitis E virus infection in pregnant women infected with hepatitis B virus and antibody placental transfer in infants

BackgroundHepatitis E has poor outcomes in pregnant women. Superinfection of hepatitis E virus (HEV) in patients infected with hepatitis B virus (HBV) may worsen liver disease.ObjectivesTo estimate the incidence and seroprevalence of HEV infection among HBV-infected pregnant women, to investigate the transplacental transfer of maternal anti-HEV IgG, and to compare the maternal and neonatal outcomes in anti-HEV positive and negative pregnant women.Study designTotally 391 HBV-infected pregnant women were recruited from April 2012 to October 2014. Paired mothers and infants were followed up at an average 9.8 months postpartum. Anti-HEV IgG and IgM were tested by ELISA.ResultsOf the pregnant women, none was anti-HEV IgM positive and 42 (10.7%) were IgG positive. At the follow-up, 3 seronegative women converted to anti-HEV IgG positive, with an estimated incidence of 17 per 1000 person-years. No significant differences of gestational age, preterm birth rate, Apgar score and birthweight were observed between newborns of anti-HEV IgG positive and negative mothers. Of the 42 neonates born to anti-HEV IgG positive mothers, 38 (90.5%) had anti-HEV IgG in their cord blood. The neonatal and maternal anti-HEV IgG levels were positively correlated (r = 0.827, p < 0.05). All infants were negative for both anti-HEV IgM and IgG at the follow-up.ConclusionsHBV-infected pregnant women rarely have novel HEV infection during late pregnancy in Jiangsu, China. Maternal anti-HEV IgG efficiently transfers into the fetuses, and disappears in infants before 10 months old.     

散发性急性肝炎抗甲型和戊型肝炎病毒IgM抗体的检测与分析

目的 了解北京地区散发性急性甲型和戊型肝炎的年龄分布、肝功能损伤和预后。方法 用酶免疫法（EIA）检测1995年1月至2000年6月北京地区散发性急性肝炎患者抗甲型肝炎病毒IgM(HAV-IgM)和抗戊型肝炎病毒IgM(HEV-IgM）。结果 在203例散发性急性肝炎患者中,有112例为甲和戊型肝炎病毒感染,合计阳性率占55.2％,其中甲型肝炎占22.2%,戊型肝炎占33％。甲、成语地炎患者均有不同程度肝脏损伤,约75％的患者有中至重度的肝功能损伤（ALT值＞500－≥3500U／ml）,比较重症甲型和戊型肝炎患者肝功能损伤程度（ALT值≥1000－≥3500U/ml）。甲型肝炎患者高于戊型肝炎。追踪患者系列血清及观察临床症状,患者均在2－3个月恢复,ALT转为正常,黄疸消退,未发现甲型和戊型肝炎慢性化病例。结论 散发性急笥肝炎患者一半以上是由肠道传染的甲型和戊型肝炎病毒感染引起,甲型肝炎发病年龄主要以青年居多,戊型肝炎发病主要以青壮年为主,大多数甲肝炎病毒感染引起,甲型肝炎发病年龄主要以青年居多,戊型肝炎发病主要以青壮年为主。大多数甲型和戊型肝炎患者有中至重度的肝功能损伤。在我国病毒性肝炎的防治策略上,对散发性的甲、戊型肝炎的预防应引起同样高度重视。     

甲型肝炎病毒P1B、P2A、P3AB和P3D蛋白在原核系统中的表达和抗原活性分析

目的研究甲型肝炎病毒P1B、P2A、P3AB和P3D在原核系统中的表达,并探讨这些蛋白的抗原活性和作为诊断抗原的应用价值。方法采用PCR方法,从克隆有HAV HM175株全长cDNA基因的克隆载体pHAV16H1上扩增出目的基因,以M47作为表达载体,构建N端带硫氧还蛋白的重组表达质粒。重组质粒在大肠埃希菌BL21(DE3)中经IPTG诱导表达。采用DEAE阴离子交换和镍离子柱螯和亲和层析纯化的方法对重组蛋白进行纯化。以Western Blot和间接ELISA的方法检测重组蛋白的抗原活性。结果四个重组质粒经测序证明构建正确无误,在大肠埃希菌中表达四个蛋白的相对分子质量也正确无误。Western Blot分析和间接ELISA方法证实四个蛋白中只有p2a有抗原活性。结论原核表达的P2a蛋白,具有较好的抗原活性,在间接ELISA方法中检测出了所有的24份阳性血清和24份阴性血清,非常有希望做成诊断抗原用于诊断急性甲肝患者和区分甲型肝炎自然感染与注射疫苗所产生的不同免疫。     

甲型肝炎病毒的纯化及其单抗的制备

应用不连续蔗糖／甘油密度梯度超速离心的方法，从培养细胞中纯化甲肝病毒（Ｈｅ－ｐａｔｉｔｉｓＡＶｉｒｕｓ，ＨＡＶ）。纯化的ＨＡＶ抗原经ＳＤＳ－ＰＡＧＥ电泳分析，获得三条带：ＶＰ１（３４０００），ＶＰ２（３００００）和ＶＰ３（２６０００）。用纯化的ＨＡＶ抗原免疫Ｂａｌｂ／ｃ小鼠，将已免疫小鼠的脾细胞与ＳＰ２／０细胞融合，获得６株分泌抗ＨＡＶ单克隆抗体的杂交瘤。它们的培养上清和腹水的抗体滴度分别是５０～１０００和１０００～４０００。Ｉｇ亚类５株为ＩｇＧ１，１株为ＩｇＧ２ａ。采用间接的ＥＬＩＳＡ法分析ＨＡＶ抗原的抗原位点，结果表明ＨＡＶ抗原至少存在４个抗原位点，两个存在于ＶＰ１蛋白带，另两个分别存在于ＶＰ２和ＶＰ３蛋白带     

Immunogenic epitopes on the surface of the hepatitis A virus capsid: Impact of secondary structure and/or isoelectric point on chimeric virus assembly

Hepatitis A virus (HAV) protein 2A has the capacity to harbor and expose a short foreign epitope. The chimeric virus, HAV-gp41, bearing seven amino acids of the 2F5 epitope of the HIV glycoprotein gp41, was shown to replicate in cell culture and laboratory animals and to induce a humoral immune response. As an extension of this work, we now investigated the possibility to insert longer epitopes, their impact on genetic stability, and the production of chimeric HAV. Twenty-seven amino acid residues of either HIV gp41, comprising the 2F5 epitope, or of a mimotope (F78) of the hypervariable region 1 of the hepatitis C virus (HCV) envelope protein E2 were inserted near the C-terminus of HAV 2A and viral capsid formation and replication were studied. The genome of the chimeric virus (HAV-F78) had reduced replication ability, yet the sedimentation profile of the chimeric particles was unchanged and the HCV sequence was maintained over serial viral passages. In contrast, no capsids were formed when an extended HIV epitope of 27 residues was inserted, precluding the rescue of infectious chimeric virus. Based on structural analyses, the data suggest that the isoelectric point (pI) and/or the secondary structure of the chimeric proteins are essential determinants that affect HAV particle formation for which protein 2A serves as an assembly signal.     

1995至2000年北京地区散发性急性肝炎患者肝炎病毒抗体的检测与分析

目的 了解北京市地区散发性肝炎患者甲型、乙型、丙型和戊型肝炎病毒感染型别分布及重叠感染。方法 用EIA法检测1995斫2月至2000年12月北京地区散发性急性肝炎患者抗－HAVIgM、HBsAg／抗－HBcIgM、抗－HCVIgM/IgG和抗－HEVIgM/IgG。结果 214例散发性急性肝炎患者血清,抗甲、乙、内和戊型肝炎病毒IgM总阳性数155例,戊型肝炎76例。有9名患者检出2种肝炎病毒抗原或抗体阳性,其中在3名肝硬化患者和2名静脉吸毒者同时检测到HBV和HCV抗原或抗体,1例HBsAg阳性者检测到抗－HAVIgM,3例－HCVIgG阳性者中分别检测到2例抗－HBVIgM和1例抗－HEVIgM。肝炎病毒重叠感染的9名患者年龄在31岁至49岁之间。结论 北京地区散发性急性肝炎78％是由消化道传染的甲戊型肝炎病毒引起,戊型肝炎在四种肝炎中位居首位,其次为甲型肝炎、乙型肝炎和丙型肝炎。肝炎病毒重叠感染多见乙、丙型肝炎病毒合并感染或慢性乙、丙型肝炎患者合并甲型或戊型肝炎病毒感染。在我国对散发性病毒性肝炎的预防应引起高度重视。     

一种改良的环介导恒温扩增技术在甲型肝炎病毒核酸检测上的应用

目的 建立一种更加快速简便的环介导恒温扩增技术(LAMP)检测甲型肝炎病毒(HAV).方法 本研究通过在传统LAMP的基础上加入加速引物建立了一种改进型的LAMP体系.结果 精确性和可重复性实验证实改进后的HAV LAMP检测体系稳定可靠,重复性强,并且较传统的LAMP灵敏度更高,检测极限可以达到5 TCID50/ml.当该方法用于甲型肝炎患者急性期血清临床样本的检测时,实验结果与TaqMan实时荧光定量PCR的检测结果一致.结论 改进型的LAMP技术有望应用于HAV临床样本检测,同时也适用于HAV流行地区的病原学监测和调查.     

Changes in the seroprevalence of IgG anti-hepatitis A virus between 2001 and 2013: experience at a single center in Korea

Background/Aims

The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Korean during the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to children aged <10 years. In the present study we analyzed the changes in the seroprevalence of IgG anti-hepatitis A virus (HAV) over the past 13 years.

Methods

Overall, 4903 subjects who visited our hospital between January 2001 and December 2013 were studied. The seroprevalence of IgG anti-HAV was analyzed according to age and sex. In addition, the seroprevalence of IgG anti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), mid-to-late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis.

Results

The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, compared to the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedly increased among individuals aged 1-14 years and decreased among those aged 25-44 years (P<0.01). We also found that the seroprevalence of IgG anti-HAV in individuals aged 25-44 years in the early 2010s was lower than that in the early 2000s and mid-to-late 2000s.

Conclusions

The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgG anti-HAV is low in the active population.     

Natural NS5A inhibitor resistance associated substitutions in hepatitis C virus genotype 1 infected patients from Italy

ObjectivesGenetic variability in NS5A is associated with different levels of resistance to the currently licensed NS5A inhibitors. The aim of this study was to detect NS5A inhibitor resistance associated substitutions (RASs) in hepatitis C virus (HCV) genotype 1 (GT1) patients who are naive to direct-acting HCV antivirals.MethodsAmplification, Sanger sequencing and phylogenetic analysis of the HCV NS5A region were performed on plasma obtained from 122 consecutive patients with HCV chronic infection attending four different clinics in Italy.ResultsNS5A inhibitor RASs were detected in 14/61 (23.0%) HCV GT1b and 3/61 (4.9%) HCV GT1a infected patients (p 0.007). The pan-genotypic RAS Y93H was detected in 1 (1.6%) GT1a and 4 (6.6%) GT1b patients. GT1a sequences clustered into two different clades with RASs detected in 1/34 (2.9%) clade I and 2/27 (7.4%) clade II sequences.ConclusionsAlthough the impact of naturally occurring NS5A RASs might be limited with upcoming pan-genotypic treatment regimens, this information is still useful to map naturally occurring HCV variants in different geographic areas in the context of current HCV therapy.