HBV感染性克隆长度对其复制能力的影响

目的比较不同长度HBV感染性克隆复制能力的差异,为HBV复制相关研究提供依据。方法采用分子克隆的方法体外分别扩增HBV基因组的相应片段,并进行连接,分别构建含1.1、1.2、1.3倍HBV基因组的可复制性克隆。体外转染Huh7细胞系评价抗原分泌和病毒复制情况,使用高压水注射建立急性感染小鼠模型评价病毒分泌情况以及抗原在小鼠肝脏内的表达情况。结果所构建的克隆体外转染Huh-7细胞后均可分泌高浓度的HBsAg,而1.3倍HBV基因组的可复制性克隆HBeAg的分泌能力明显强于其他克隆,转录水平也最高。高压尾静脉注射小鼠后肝组织内均可检测到HBcAg的分布,血清中可以检测到HBV DNA并随时间发生动态变化。其蛋白表达水平和病毒分泌能力均以1.3倍HBV基因组的可复制性克隆较高。结论所构建的克隆在体外及体内均可进行复制,其中含HBV全基因组1.3倍体的可复制性克隆的复制能力最强,可以较好反映来源病毒株的天然复制能力。     

Liver histology and immunohistochemical findings in asymptomatic Indians with incidental detection of hepatitis B virus infection.

BACKGROUND AND OBJECTIVES: The relationship between hepatocyte expression of hepatitis B virus (HBV) antigens, liver histology and viral replication in asymptomatic subjects with incidental detection of hepatitis B surface antigen (HBsAg) remains unclear. We evaluated the histological activity index (HAI) and hepatocyte expression of viral antigens with replicative status in asymptomatic chronic HBV infection. METHODS: Asymptomatic subjects with incidental detection of HBsAg and ALT levels less than twice the upper limit of normal were grouped as follows: Group A - negative for HBeAg and HBV DNA (no HBV replication); B - HBeAg negative, HBV DNA positive (low HBV replication or pre-core mutant); C - positive HBeAg and HBV DNA (high viral replication). Liver biopsies were assessed for HAI (Ishak's scoring system). These were also subjected to immunohistochemistry for expression of HBsAg and hepatitis B core antigen (HBcAg); distribution, staining pattern and quantitative measurement of antigen expression were assessed. RESULTS: Median HAI was similar in the three groups (1.0, 2.0 and 2.0 in groups A, B and C, respectively). All subjects in Group C showed discrete cytoplasmic expression of HBsAg, whereas the other two groups showed heterogeneity in distribution and pattern of HBsAg staining. Quantitative measurement of cytoplasmic HBsAg revealed similar results in the three groups. Core antigen (nuclear) was detected in 4 of 5 subjects in Group C and none of those in Groups A and B. Ground-glass hepatocytes were seen in 20 and orcein-positive cells in 26 cases. HBsAg was detected by immunohistochemistry in 37 biopsies. CONCLUSIONS: Among asymptomatic subjects with chronic HBV infection, those with high rate of viral replication had discrete cytoplasmic HBsAg expression and nuclear expression of core antigen; these findings were uncommon in subjects with low or no viral replication.     

原代培养人胎肝细胞体外感染HBV的研究

目的建立HBV感染人胎肝细胞体外培养系统。方法 首先分离、培养人胎肝细胞，然后应用HBV阳性血清感染体外培养的人胎肝细胞；每隔2d收集上清液和肝细胞，应用ELISA,免疫组化法、原位杂交法和斑点杂交法检测上清液和细胞中HBsAg和HBV DNA。结果 上清液中HBsAg在感染后2d～20d均可测出，以感染后4d～16d达高峰(A值在0．22左右)。免疫组化检测细胞中HBsAg呈阳性表达，原位杂交和斑点杂交检测细胞和上清液中HBV DNA也呈阳性表达。结论 HBV在原代培养人胎肝细胞中能稳定复制和表达至少达16d。     

Diverse virological, histopathological and prognostic implications of seroconversion from hepatitis B e antigen to anti-HBe in chronic hepatitis B virus infection

The evolutions of serum hepatitis B virus (HBV)-DNA, liver histology and intrahepatic expressions of HBV antigens were longitudinally investigated in 24 serum HBeAg+/HBV-DNA+ chronic hepatitis B patients who subsequently seroconverted to anti-HBe. After HBeAg conversion, serum HBV-DNA still persisted in 10 patients, and liver HBcAg in 7 of them. Of the 24 patients, 3 subgroups with diverse prognoses were identified. Ten patients progressed from chronic active hepatitis to cirrhosis, and in 7 of them HBV-DNA and/or HBcAg persisted. Eight patients with undetectable HBV-DNA and HBcAg recovered. In the remaining 6 patients, chronic liver diseases persisted; in 3 of them, HBV-DNA and in one HBcAg. These findings indicate that continued viral replication is present in a significant number of patients after HBeAg seroconversion in Taiwan, and is responsible for disease progression. In addition to HBcAg and HBV-DNA, the severity of underlying liver histology, when HBeAg seroconversion occurred, was critical for the outcome of the disease. Another remarkable finding was that clusters of ground-glass hepatocytes, well correlated with the marginal expression of HBsAg, were demonstrated in 14 of 16 biopsies with serum anti-HBe+/HBV-DNA-, but found in only 4 of 44 biopsies with positive serum HBV-DNA, indicating a strong association of the expressions of liver histology and hepatocyte HBsAg with the status of viral replication.     

Hepatitis B virus DNA (HBV-DNA) in anti-HBe positive sera

HBV-DNA measured by the spot hybridization technique, was found in the sera of 28 of 106 (26.4%) anti-HBe positive carriers of HBsAg. Dane particle-associated HBeAg, HBcAg and HBV-specific DNA-polymerase activity were found in the sera of nine (8.5%), five (4.7%) and two (1.9%) of these patients, respectively. All carriers with serum HBV-DNA had chronic liver disease and 18 had intrahepatic delta-Ag and serum anti-delta at titers higher than 1/5000. Intrahepatic HBcAg was detected in the nuclei of 90% of delta negative individuals; 50% of them also had cytoplasmic fluorescence. Only two of the 18 patients with intrahepatic delta-Ag (11%) had HBcAg in the liver. Viral nucleic acid was not found in the sera of 15 other patients with chronic hepatitis, seven of whom had intrahepatic delta-Ag. Serum HBV-DNA was also negative in the remaining 63 symptomless carriers of HBsAg lacking markers of delta infection. Interestingly, although DNA-polymerase negative, some sera gave autoradiographic spots of high optical density. HBV-DNA was detected in them at concentrations typical of sera which are usually both DNA-polymerase and HBeAg positive. Detection of HBV-DNA in serum represents the most direct and sensitive in vitro assay for assessing HBV infectivity and characterizes HBsAg carriers with HBV-related liver damage and ongoing HBV replication independently from the state of HBeAg/anti-HBe system. In the Mediterranean area, the majority of anti-HBe positive carriers with serum HBV-DNA have chronic liver disease and delta infection.     

Replication and gene expression of mutant hepatitis B virus in a transgenic mouse containing the complete viral genome with mutant s gene

AIM: To establish the transgenic mouse line harbouring complete hepatitis B virus (HBV) genome with mutant s gene (adr subtype). METHODS: Transgenic mice were generated by microinjecting HBV genome into fertilized eggs. Integration, expression, replication of HBV gene and histological changes in transgenic mice were estimated by genomic DNA PCR, serum DNA PCR, Southern blot, ELISA, HE staining, immunohistochemistry and transmission electron microscopy. Transgenic mice with HBsAg positive in serum were bred and analyzed. RESULTS: A total of 288 eggs survived from microinjections were transplanted into the oviducts of 13 pseudopregnant mice and 49 pups were produced. Twenty-six mice were identified to have the integrated HBV gene. Serum HBsAg and HBeAg were detected in 2 of 43 mice. HBsAg and HBcAg in cytoplasm or nuclei of hepatocytes were detected in 10 mice. Founders with HBsAg in serum were named lineages G145R-15 and G145R-18. Of the 16 F1 offsprings generated by G145R-15 founder, 12 were positive for HBV genome with PCR, 10 were positive for HBsAg and HBcAg with immunohistochemistry and 7 were positive for HBsAg and HBeAg with ELISA. Only 1 of 8 F1 offsprings generated by G145R-18 founder was survived and it was detected positive for HBV genome, HBsAg, HBcAg and HBeAg. Both of the two lineages had some pathological characteristics of mild chronic hepatitis B in the liver, such as swelling of hepatocytes and focal hepatocellular necrosis and parenchymal lymphomononuclear cell infiltrate. CONCLUSION: Transgenic mice harbouring HBV with mutant s gene can be generated. The HBV genes are integrated in the transgenic mice genome and can be expressed, replicated, packaged and excreted. HBV DNA can be stably transmitted in the transgenic mice.     

B基因型乙型肝炎病毒感染性克隆的构建及其复制能力评价

目的 构建在亚太地区广泛流行的B基因型HBV可复制性克降,为该基因型相关研究奠定基础.方法 采用分子克隆的方法在体外分别扩增HBV基因组的相应片段,并进行连接,构建含1.3倍HBV基因组的可复制性克隆.体外转染Huh7细胞系以评价其抗原分泌和病毒复制的情况,使用高压尾静脉注射建立急性感染小鼠模型以评价体内病毒分泌情况以及肝内抗原表达的情况.结果 所构建的克隆体外转染Huh7细胞后可分泌高浓度的HBsAg和HBeAg,并可以检测到明显的转录子和复制中间体.高压尾静脉注射小鼠后肝组织内可检测到HBcAg表达,血清中可以检测到HBV DNA,其水平随时间发生动态变化.结论 所构建的克隆在体外及体内均可进行复制,具有良好的复制能力.     

流体动力学法乙型肝炎病毒感染动物模型的建立

目的:建立一种简便、有效、稳定的乙型肝炎病毒(HBV)感染的动物模型,观察该模型动物体内不同时间点各种HBV标志物的表达情况．方法:以流体动力学法尾静脉注射BALB／c 小鼠pcDNA3．1-HBV,1 wk内检测各种HBV 标志物,时间分辨免疫荧光分析法(IFMA)检测血清中HBsAg,HBeAg,抗HBs,抗HBe,抗 HBc,荧光定量PCR法(FQ-PCR)检测血清HBV DNA,免疫组织化学法检测肝组织HBsAg和 HBcAg．结果:成功建立一种急性HBV感染动物模型, 第1天血清中HBsAg表达达高峰,后逐渐降低, HBeAg表达量少,分别在第4、5、7天检测到抗HBc,抗HBe,抗HBs,d1 HBV DNA滴度亦达高峰,后渐下降,免疫组织化学示HBsAg呈胞质内弥漫性分布,HBcAg亦主要为胞质型分布．结论:以流体动力学法建立的HBV模型是一种新型有效的HBV感染动物模型,能稳定较高水平表达大部分HBV标志物．     

Assessment of HBV replicative status by receptors for polymerized human albumin

Receptors for polymerized human albumin (pHSA-r) are expressed on HBsAg in larger numbers during complete viral replication. We have evaluated the usefulness of pHSA-r as a marker of high-level infection by a comparison with serum HBeAg, liver HBcAg and serum HBV-DNA. One-hundred-and-fifty-seven patients with HBsAg positive chronic liver disease were tested for HBeAg and pHSA-r titre. In 73 of them liver HBcAg was tested by immunofluorescence, while in the remaining 84 serum HBV-DNA was determined. Seventy-three subjects were HBeAg positive, 20/73 were HBcAg positive, and 60/84 had circulating HBV-DNA. The best cut-off for pHSA-r was found at 1:204,800 (sensitivity of 67.6% and specificity of 95.7% in detecting viral replication). At this cut-off the concordance rate between pHSA-r and viral replication (as assessed by HBV-DNA or liver HBcAg) was 83%, a figure similar to that of HBeAg (88%). Three HBeAg negative subjects who were actually complete replicators were identified by the pHSA-r test.     

A case of HBs antigen negative fulminant hepatitis with IgM antibody to hepatitis B core antigen persisting more than seven years

A 33-year old dentist developed fulminant hepatitis. At admission, a test for IgM antibody to hepatitis B core antigen (IgM anti-HBc) was positive, while tests for HBsAg and HBeAg were negative. He was cured of the disease, but in follow-up examinations from 1983 to 1990 IgM anti-HBc was continuously detected with radioimmunoassay while HBsAg and HBV-DNA were absent in the serum. However, HBcAg was found in a biopsied liver specimen and a small quantity of HBV-DNA was detectable by polymerase chain reaction assay. These observation suggest that the continuous detection of IgM anti-HBc without HBsAg in serum is due to persistent HBV infection and HBV replication in the liver.     

A case of HBs antigen negative fulminant hepatitis with IgM antibody to hepatitis B core antigen persisting more than seven years.

A 33-year old dentist developed fulminant hepatitis. At admission, a test for IgM antibody to hepatitis B core antigen (IgM anti-HBc) was positive, while tests for HBsAg and HBeAg were negative. He was cured of the disease, but in follow-up examinations from 1983 to 1990 IgM anti-HBc was continuously detected with radioimmunoassay while HBsAg and HBV-DNA were absent in the serum. However, HBcAg was found in a biopsied liver specimen and a small quantity of HBV-DNA was detectable by polymerase chain reaction assay. These observation suggest that the continuous detection of IgM anti-HBc without HBsAg in serum is due to persistent HBV infection and HBV replication in the liver.     

慢性乙型肝炎患者肝组织HBV cccDNA、总HBV DNA与血清HBV DNA的相关性及其与临床的关系

目的探讨慢性乙型肝炎患者肝组织HBV共价闭合环状DNA（cccDNA）、肝组织总HBV DNA（HBV tDNA）与血清HBV DNA之间的相关性及其与临床的关系。方法 78例慢性乙型肝炎患者入选本研究。肝组织β- globinDNA、HBV cccDNA和HBV tDNA采用实时荧光定量PCR方法检测,平均每个肝细胞HBV cccDNA和HBV tDNA含量（拷贝/cell）=HBV cccDNA（实测值）/β-globin DNA（实测值）和HBV tDNA（实测值）/β3-globin DNA（实测值）,肝组织HBV cccDNA和HBV tDNA含量的计算单位定义为log₁₀拷贝/10⁶cell;采用实时荧光定量PCR、ELISA法检测血清HBVDNA和HBV标志物;采用免疫组织化学方法检测肝细胞中HBsAg和HBcAg的表达。统计分析采用pearson相关分析及t检验。结果 （1）肝组织HBV cccDNA与HBV tDNA定量呈正相关（r=0.696,P<0.001）;肝组织HBV cccDNA与血清HBV DNA定量呈正相关（r=0.304,P<0.01）;肝组织HBV tDNA与血清HBV DNA定量呈正相关（r=0.341,P<0.01）;（2）肝细胞内HBcAg定性检测阳性患者的血清HBV DNA定量明显高于阴性患者,且差异有统计学意义（P<0.05）;肝细胞内HBcAg定性检测阳性患者与阴性患者的肝组织HBV cccDNA和HBV tDNA定量差异均无统计学意义和（P均>0.05）;（3）肝细胞内HBsAg定性检测阳性患者的血清HBV DNA定量明显高于阴性患者,且差异有统计学意义（P<0.05）;肝细胞内HBsAg定性检测阳性患者与阴性患者的肝组织HBV cccDNA和HBV tDNA定量差异均无统计学意义（P>0.05）;（4）HBeAg（+）/抗-HBe（-）患者血清HBV DNA定量明显高于HBeAg（-）/抗-HBe（+）患者,且差异有统计学意义（P<0.05）;HBeAg（+）/抗-HBe（-）患者肝组织HBV cccDNA和HBV tDNA定量与HBeAg（-）/抗-HBe（+）患者比较差异均无统计学意义（均P>0.05）;（5）肝组织HBV cccDNA、HBV tDNA以及血清HBV DNA三者与肝脏炎症活动度及纤维化程度均无显著相关性（P>0.05）。结论 （1）血清HBV DNA定量结果并不一定能完全反映患者肝组织中HBV cccDNA和HBV tDNA含量,尤其在血清HBV DNA<500拷贝/mL时,肝组织中仍存在HBV cccDNA和HBV tDNA,且含量大小不等。（2）肝细胞内HBcAg定性检测阳性或者HBsAg定性检测阳性患者的血清HBV DNA定量均明显高于阴性患者;而两者的肝组织HBV cccDNA和HBV tDNA定量均没有显著差异;（3）HBeAg（+）/抗-HBe（-）患者血清HBV DNA定量明显高于HBeAg（-）/抗-HBe（+）患者,而两者的肝组织HBV cccDNA和HBV tDNA均没有显著差异;（4）肝组织HBV cccDNA、HBV tDNA及血清HBV DNA与肝脏炎症活动度和纤维化程度均无显著相关性。     

Replication of hepatitis B virus in primary duck hepatocytes transfected with linear viral DNA

AIM: To explore the expression and replication of hepatitis B virus (HBV) DNA in primary duck hepatocytes (PDHs). METHODS: Complete HBV genome was transfected into PDHs by electroporation (transfected group, 1.19×1012 copies of linear HBV DNA/1×107 PDHs). After 1-5 d of transfection, HBsAg and HBeAg in the supernatant and lysate of PDHs were measured with the IMX System. Meanwhile, replicative intermediates of HBV DNA were analyzed by Southern blotting and Dot blotting. PDHs electroporated were used as control group. RESULTS: HBsAg in the hepatocyte lysates of transfected group was 15.24 (1 d), 14.55 (3 d) and 5.13 (5 d; P/N values, positive≥2.1) respectively. HBeAg was negative (<2.1). Both HBsAg and HBeAg were negative in the supernatant of transfected group. Dot blotting revealed that HBV DNA was strongly positive in the transfected group and negative in the control group. Southern blot analysis of intracellular total DNA indicated that there were relaxed circular (rc DNA), covalently closed circular (ccc DNA), and single-stranded (ss DNA) HBV DNA replicative intermediates in the transfected group, there was no integrated HBV DNA in the cellular genome. These parameters were negative in control group. CONCLUSION: Expression and replication of HBV genes can occur in hepatocytes from non-mammalian species. HBV replication has no critical species-specificity, and yet hepatic-specific regulating factors in hepatocytes may be essential for viral replication.     

Hepatitis B virus markers in peripheral blood mononuclear cells]

Recent studies have shown tropism of the hepatitis B virus (HBV) by peripheral blood mononuclear cells (PBMC). The consequences of this phenomenon and their clinical use are not yet clear, however. Seventy-nine patients were studied between March 1989 and October 1990. Sixty-nine patients had chronic liver disease with histological evaluations, and 10 were vaccinated for HBV. The following markers were determined: serum: HBsAg, HBeAg, anti-HBe, antitotal-HBc, anti-HBs, anti-HCV, HBV-DNA; lysated PMBC cells: HBsAg, HBeAg. Hepatic tissue: HBsAg, HBcAg. Four groups were formed according to serology. Group I--positive HBsAg patients (n = 25) HBsAg was observed in the lysated of PBMC in 19 (76%) of the patients. HBeAg in PBMC was detected in 8 (32%), all of them showed evidence of viral replication (presence of HBcAg and/or HBV-DNA in the serum HBcAg in the tissue). Group II--antitotal HBc/anti-HBs positive (n = 14), HBsAg in PBMC was found in 5 (36%) and HBeAg in 1 (7.0%). In this patient replication markers in the serum and in the tissue (HBV-DNA, HBcAg) was also present. Three patients out of 9 anti-HBs positive had HBsAg in PBMC. Group III--seronegative patients for HBV. HBsAg was present in PBMC in 2 (6.6%) of the patients, but was absent in all of them. There was concomitant presence of HBsAg in MN and the hepatic tissue in 1 patient. Replication markers were not observed in the group. Group IV--10 asymptomatic individuals vaccinated for HBV. Except anti-HBs in serum, no other HBV marker could be identified in serum or in PBMC.(ABSTRACT TRUNCATED AT 250 WORDS)     

Contribution of low level HBV replication to continuing inflammatory activity in patients with anti-HBe positive chronic hepatitis B virus infection

The relationship between the histological diagnosis and serological and tissue markers of HBV replication in 41 Greek and 29 British patients with chronic HBV infection were studied. All the nine Greek and 13 British patients who were HBeAg positive had HBV-DNA in serum and HBcAg expression in the hepatocytes. The majority (73%) of these patients had active liver disease. Forty seven per cent of the Greek and 19% of the British patients who were anti-HBe positive continued to display HBcAg in the liver with or without HBV-DNA detected in serum. All but three of these patients had persistently active liver disease. Continuing inflammatory activity in the liver, however, was also found in 31% of anti-HBe positive patients who had no evidence of HBV replication. In these patients, other factors such as delta agent, NANB viruses, alcohol abuse or an autoimmune reaction initiated by HBV may be contributory.     

乙型肝炎病毒在异种动物原代肝细胞中复制与表达的研究

目的 探讨乙型肝炎病毒(HBV)DNA复制和表达的跨种属特异性。 方法 分离培养原代大鼠肝细胞(PRH)与原代鸭肝细胞(PDH),电转HBV线性裸DNA(转染组每1×107PRH或PDH 1.19×1012拷贝),分别于转染后1～15d各时点,收集PRH或PDH培养上清液与细胞裂解液,分别以Southern杂交分析和斑点杂交法分析HBV DNA的复制中间体与复制型式;以全自动免疫荧光检测系统检测乙型肝炎表面抗原(HBsAg)、乙型肝炎e抗原(HBeAg),以western免疫印迹、免疫斑点印迹和免疫细胞化学法检测乙型肝炎核心抗原(HBcAg);用逆转录聚合酶链反应检测HBV S/X mRNA。以单纯电击PRH/PDH为对照组。 结果 Southern杂交分析显示:PRH/PDH转染组HBV DNA均为游离复制型,可见4.0 kb以下分子区带,包括松弛环状DNA、共价闭环形DNA和单链线形DNA等复制中间体;未见整合型HBVDNA-高分子(4.0～24.0 kb)区带。HBV DNA在PRH中表达蛋白产物水平,HBsAg于转染后各时点PRH裂解液中均可检测到(P/N值2.17～93.41,平均值为14.74±31.82,阳性≥2.1),峰值于1～3 d;仅转染后1d PRH培养上清液中检测到HBsAg,P/N值为6.66;HBcAg和HBeAg仅于转染后1～3 d时点内检测到低度表达;HBV S mRNA为阳性,而X mRNA为阴性。HBV DNA转染PDH组,转染后1、3、5 d各时点PDH裂解液中HBsAg分别为15.24、     

日本血吸虫重叠 HBV 感染小鼠模型的建立

目的：建立日本血吸虫重叠 HBV 感染小鼠模型,观察其生物学表现。方法日本血吸虫尾蚴感染6～8周龄雌性 BALB／cJ 小鼠,8周后,通过高压尾静脉注射 B 基因型 HBV 可复制性克隆,分别在注射后第3、7天,检测血清HBV DNA、HBsAg、HBeAg、ALT、透明质酸（HA）水平;检测 HBcAg 在肝细胞内表达情况和虫卵肉芽肿形成情况。比较重叠感染相关生物学指标和单独感染组的不同。结果重叠感染组小鼠肝组织内可见 HBcAg 在虫卵肉芽肿周围肝细胞内表达;可以正常分泌 HBsAg 和 HBeAg 以及子代病毒;其血清 ALT 水平低于 HBV 感染组,高于血吸虫感染组;HA 含量相对明显升高。结论成功建立了日本血吸虫重叠 HBV 感染小鼠模型,为后续研究此类重叠感染提供了良好的小动物实验平台。     

拉米夫定治疗慢性乙型肝炎的临床观察及病理学研究

目的观察拉米夫定治疗慢性乙型肝炎患者的临床疗效、肝组织学改变及肝组织内乙型肝炎病毒(HBV)标志物的变化。方法随机选择70例慢性乙型肝炎患者予口服拉米夫定100mg／d，连用1年。观察HBVDNA、血清HBeAg／抗-HBe、肝功能以及血清肝纤维化指标的变化；对其中35例患者行治疗前后肝穿刺活检，行Knodell病理学评分，检测肝细胞内HBsAg、HBcAg、α平滑肌肌动蛋白(α-SMA)。结果治疗结束时，完全应答率为23．73％，部分应答率为69．49％，无应答率为6．78％。发生HBeAg血清学转换的患者治疗前血清ALT水平明显高于未发生血清HBeAg转换的患者。41．18％患者肝组织学活动指数得以改善，汇管区坏死、门静脉炎症及纤维化明显改善。血清HBeAg转换组肝组织内HBcAg、α-SMA的表达明显减少．HBsAg的表达无显著性改变。治疗期间不良反应轻，安全性良好。结论拉米夫定100mg／d可以迅速降低血清HBvDNA和ALT的水平，促进HBeAg血清转换，减轻肝脏炎症坏死活动度，延缓肝纤维化的进展。     

Biologic and prognostic significance of hepatocyte hepatitis B core antigen expressions in the natural course of chronic hepatitis B virus infection

To elucidate the biologic significance of hepatocyte hepatitis B core antigen (HBcAg) expression and its relation to the natural course of hepatitis B virus (HBV) infection, the patterns of HBcAg were correlated with HBV virus replication state and the disease activity in 598 needle liver biopsies performed on 569 hepatitis B surface antigen (HBsAg) carriers aged 1-81 years. A good correlation of liver HBcAg with serum HBeAg and HBV DNA status was demonstrated. HBcAg was present in the hepatocyte nuclei (nHBcAg) or cytoplasm (cHBcAg), or in both (mixed). Pure nHBcAg was seen mainly in children and young adults; 86% of the patients had non-aggressive disease, but rare cases of chronic active hepatitis (CAH) and HBeAg seroconversion were observed. In contrast, cHBcAg was predominantly associated with CAH (52%) and accompanied by a significantly higher HBeAg seroconversion rate (27%). The HBeAg-negative group, particularly the liver HBcAg-negative subgroup, had a lower frequency of CAH, but an increased incidence of non-aggressive disease as well as cirrhosis and/or hepatocellular carcinoma, indicating that HBeAg seroconversion to anti-HBe does not necessarily mean a favorable prognosis. The results suggest that expression of HBcAg correlates with the liver pathology and the three phases of chronic HBV infection: (1) the early immune tolerance phase is characterized by nHBcAg, mild disease and low HBeAg seroconversion rate; (2) the virus replication/elimination phase by cHBcAg or negative HBcAg, frequent CAH, and high HBeAg seroconversion rate; and (3) the inactive virus replication phase by negative HBcAg and a bipolar disease spectrum.     

乙型肝炎病毒转基因小鼠免疫耐受状态及血液生物化学指标的研究

目的 了解HBV转基因鼠HBV基因的复制表达和免疫耐受状态,为探讨乙型肝炎发病机制和抗HBV新药评价提供可靠的参考依据.方法 选取遗传背景相同的SPE级HBsAg阴性非转基因鼠和转基因鼠.化学发光法检测HBsAg、HBeAg、HBV DNA,ELISA检测前S1、HBcAg,肝组织行病理学检查,免疫组织化学染色检测不同时期转基因鼠肝HBsAg表达,流式细胞仪检测小鼠淋巴细胞增殖情况,酶联免疫斑点检测(ELISPOT)分泌IFNγ的T淋巴细胞斑点数,双色免疫荧光法检测脾细胞悬液和脾树突状细胞(DC)中Toll样受体(TLR)2和TLR9的表达.数据行t检验和F检验.结果 HBV转基因鼠可复制表达HBsAg、前S1、HBeAg、HBcAg和HBVDNA,而抗-HBs、抗-HBc、抗-HBe均阴性;肝组织无明显病理改变,肝细胞中HBsAg在胞质表达,HBcAg在胞核表达.HBsAg刺激后,HBV转基因鼠T淋巴细胞增殖能力为(697.6±67.3)cpm,显著低于非转基因鼠的(1315.5±191.6)cpm.经HBsAg刺激后,HBV转基因鼠脾细胞分泌IFNγ的T淋巴细胞斑点数为8.25±1.10,低于非转基因鼠的28.50±4.21(F=155.967,P=0.000).HBV转基因DC表达CD11c+、TLR2和TLR9与非转基因鼠比较,差异无统计学意义(均P＞0.05).在18日龄胎鼠和1日龄仔鼠肝组织观察到HBsAg表达.结论 HBV转基因鼠有HBV相关抗原表达,并对HBV相关抗原存在免疫耐受,其先天和获得性免疫功能均正常,类似于人类慢性HBV无症状携带者.HBV转基因鼠是比较理想的动物模型.