反义锁核酸在转基因小鼠体内阻断乙肝病毒C基因表达

目的 探讨针对乙肝病毒C基因反义锁核酸在转基因小鼠体内阻断病毒基因表达的效果.方法 各实验组经尾静脉给药后,采用real-time PCR、时间分辨免疫荧光技术、免疫组织化学法等技术分别检测血清HBV DNA、HBeAg含量及肝细胞内HBcAg的表达情况.结果 注射锁核酸后,对乙肝病毒核酸的复制和乙肝病毒e抗原的合成均有较强的抑制作用,注射后1、3 和5 d,HBV DNA的平均抑制率分别19.24％、39.20％和44.47％;HBeAg的平均抑制分别为30.71％、51.14％和63.46％;小鼠肝细胞的HBcAg阳性细胞数也较对照组明显减少.结论 针对乙肝病毒C基因的反义锁核酸在转基因小鼠体内能有效抑制病毒基因的复制和表达,提示C基因可作核酸药物治疗的有效靶位.     

Characterization of T-cell tolerance to hepatitis B virus (HBV) antigen in transgenic mice.

We made three different lines of hepatitis B virus (HBV) transgenic mice which express different amounts of hepatitis B e antigen (HBeAg) and/or hepatitis B core antigen (HBcAg) to analyse the cellular mechanisms of HBcAg specific T-cell tolerance. BS10 (official designation, 1.2HB-BS10) transgenic mice, which contain the whole HBV genome, express relatively high amounts of HBeAg in the serum and HBcAg in the liver. SPC mice, which contain hepatitis B virus core and precore gene, express small amounts of HBeAg in the serum but not HBcAg in the liver. SC33 mice, which contain only hepatitis B core gene, do not express HBeAg in the serum but express HBcAg in the liver. BS10 mice showed a very low anti-HBc antibody response after primary and secondary immunizations with recombinant HBcAg compared to transgenic host C57BL/6 (B6) mice. SPC mice showed an almost equal level of anti-HBc antibody response compared to B6 mice. SC33 mice contained anti-HBc antibody even before immunization and showed high titres of anti-HBc antibody response after immunization with HBcAg. Analysis of cellular site(s) of low responsiveness of BS10 mice revealed that proliferating and helper T cells are specifically tolerant to HBcAg. B cells and antigen-presenting cells in BS10 mice were not defective. SC33, SPC and BS10 mice differ a little in their developmental expression of HBc/HBeAg. Our results suggest critical roles of the nature (circulating versus non-circulating) as well as the time of expression of self-antigens in T-cell tolerance.     

乙型肝炎病毒核心蛋白在长期培养淋巴细胞中的表达

目的 构建表达乙型肝炎病毒核心蛋白（HBcAg）的真核表达载体，并在外源性人端粒酶逆转录酶基因转导的正常人外周血淋巴细胞中进行稳定表达。方法 用PCR法获得编码乙型肝炎病毒核心蛋白的基因，利用基因重组技术构建表达该蛋白的真核表达载体，用质粒转染表达外源性人端粒酶逆转录酶的外周血淋巴细胞，间接免疫荧光及Western blot检测HBcAg在细胞内的表达。结果 表达外源性人端粒酶逆转录酶的外周血淋巴细胞能够在体外长期生存，增殖旺盛。间接免疫荧光及Western blot均能够检测到HBcAg在细胞内的表达。结论 乙型肝炎病毒核心蛋白基因在长期培养淋巴细胞中表达，建立了一种较理想的乙型肝炎病毒核心蛋白细胞模型。     

HIV-associated nephropathy in transgenic mice expressing HIV-1 genes

Transgenic mice were produced that bore copies of a defective HIV provirus. The transgenic offspring from three independently derived mouse lines manifested renal disease associated with proteinuria, a high mortality rate, and HIV-specific gene expression in the kidney. An early histopathological lesion in the kidney was focal glomerulosclerosis. Moribund animals had diffuse glomerulosclerosis with prominent microcystic tubular dilatation, tubular epithelial degeneration, and interstitial nephritis. Electron microscopy revealed ultrastructural features consistent with the glomerulosclerosis: effacement of the foot processes of visceral epithelium and an increase in mesangial cell matrix. Transgenic mice variably expressed 6-, 4.3-, and 2-kb HIV-specific RNAs and HIV-related polypeptides in several tissues including kidney. Immunocytostaining revealed the presence of HIV-related protein in the glomeruli of affected animals. Glomerulopathy in these transgenic mice and HIV-associated nephropathy in man have similar features.     

慢性乙型肝炎血清及肝组织病毒学标志与病理损伤的关系

目的探讨慢性乙型肝炎(CHB)患者血清及肝组织病毒学标志与肝组织病理损伤的关系。方法对647例CHB患者血清病毒学标志HBsAg、HBsAb、HBeAg、HBeAb、HBcAb、HBVDNA及其中418例肝细胞病毒学标志HBsAg、HBcAg的表达与肝组织病理损伤进行对比分析。结果CHB患者血清及肝组织病毒学标志与肝组织病理损伤密切相关。结论血清HBsAg、HBeAb、HBcAb阳性,HBVDNA阴性的患者肝组织炎症及纤维化程度较轻;HBVDNA与肝组织炎症分级及纤维化分期无明显相关;肝细胞HBsAg、HBcAg均阴性表达的肝组织炎症及纤维化程度较重。     

肾小球肾炎肾组织中HBV感染的标志

为了解肾组织中ＨＢＶＤＮＡ与ＨＢＶ抗原存在的关系，探讨肾组织中ＨＢＶ抗原的来源及其与病理变化的关系，我们检测２４６例肾炎肾组织中三种ＨＢＶ抗原。发现除肾小球沉积外，肾小管常有阳性表达。肾小管ＨＢｃＡｇ阳性率达２１．５４％，高于肾小球（１０．９８％）。有１８例肾组织经Ｓｏｕｔｈｅｒｎ印迹杂交检测ＨＢＶＤＮＡ，１５例阳性者中１４例肾组织ＨＢＶ抗原同时阳性，１２例血清感染标志亦阳性。结果提示某些肾炎可能与肾组织感染ＨＢＶ相关，肾组织中出现的ＨＢＶ抗原抗体免疫复合物除来自血循环外，有肾源性──原位形成的可能。     

HBV感染与IgA肾病肾小管-间质病变的关系

目的 探讨ＩｇＡ肾病ＨＢＶ感染与肾小管间质病变的关系。方法 利用原位分子杂交（ＧＨＢＶ ＤＮＡ）、免疫组化（ＨＢＡｇ、ＣＤ３、ＣＤ８）以及ＨＢＶ ＤＮＡ－ＨＢＡｇ和ＨＢＡｇ－ＣＤ４３双标记技术,对９１例ＩｇＡ肾病肾穿刺标本进行研究。结果 肾组织内ＨＢＡｇ阳性率为６９．２％。ＨＢＶ ＤＮＡ原位杂交阳性率为４２．９％。ＨＢＶ ＤＮＡ阳性的病例,双重标记染色发现ＨＢＶ ＤＮＡ阳性肾小管上皮细胞可表达ＨＢ     

Hepatitis B virus-related glomerulopathy in patients with systemic lupus erythematosus

The clinical data and renal pathologic information from three patients with systemic lupus erythematosus (SLE), active glomerular disease, and hepatitis B virus (HBV) antigenemia are presented. All three patients fulfilled the American Rheumatism Association criteria for the diagnosis of SLE. However, the renal pathologic results excluded the diagnosis of lupus nephritis. The common findings shared by these patients included the following: presence of hepatitis B surface antigen (HBsAg) in both serum and glomeruli and of glomerular hepatitis B core antigen (HBcAg), and the absence of polyclonal immunoglobulins, C1q and C4, deposition in renal tissue. These common features and the renal pathologic results indicated that the glomerulopathy was associated with HBV antigenemia. The cases described here may represent a subset of patients with SLE in whom expression of lupus nephritis was altered by the concomitant HBV-related glomerulonephritis.     

HBV与HCV融合DNA疫苗的构建及其体液免疫应答

目的 构建含乙型肝炎病毒（HBV）表面抗原基因（S区基因）与丙型肝炎病毒（HCV）核心抗原基因（C区基因）的嵌合真核表达载体,观察preS1和preS2基因对HBV表面抗原及HCV核心抗原体液免疫的影响。方法 用PCR方法,分别扩增HBV S区基因和HCV C区基因。将S区基因克隆入真核表达载体pcDNA3.1,酶切鉴定后,大量提取质粒并免疫Balb/c小鼠,用ELISA法检测抗HBs和抗HCV抗体。结果 成功地扩增出目的基因片段,克隆后酶切鉴定结果正确,序列分析与文献报告相一致。免疫后检测到抗HBs和抗HCV抗体。preS1与preS2基因对构建的融合DNA疫苗的体液免疫应答有一定的抑制作用。抗HBs抗体的产生低于只含S基因的真核表达载体;preS1基因对抗HCV抗体的产生具有抑制作用,而preS2无影响。结论 不同长度的HBV S区基因可影响抗HBs和抗HCV抗体的产生。     

Differential effect of chronic hepatitis D virus infection on intrahepatic expression of hepatitis B viral antigen.

AIMS: To determine how chronic hepatitis D virus (HDV) infection affects intrahepatic hepatitis B virus (HBV) antigen expression. METHODS: Ninety eight liver biopsy specimens from 68 patients seropositive for total antibody to HDV were studied by immunohistochemistry, and the amount of HBV antigens was also quantified by radioimmunoassay in 12 patients and compared with 30 patients with chronic HBV infection. RESULTS: Forty nine of the 68 patients were positive for intrahepatic HDV antigen and only five were positive for HBV core antigen (HBcAg). HBV surface antigen (HBsAg) was present in 55 (80.9%) patients and was always cytoplasmic in distribution. Hepatic pre-S1 and pre-S2 expressions paralleled that of HBsAg, and were detected in 53 (77.9%) and 54 (79.4%) patients, respectively. There was no relation between the intrahepatic expression of HDV antigen and HBsAg/pre-S1/pre-S2. Follow up biopsy specimens in 25 patients showed either static or deteriorating histology while intrahepatic HDV antigen remained the same or fell. The patients with intrahepatic expression of HBcAg had either absent or noticeably decreased expression of HBcAg in their follow up biopsy specimens (median two years). In contrast, HBsAg/pre-S1/pre-S2 were the same or increased (p less than 0.001). Quantification of intrahepatic HBsAg in patients with chronic HDV infection (0.61 pg/hepatocyte, range: 0.05-1.08, n = 12) showed no difference with patients with chronic HBV infection alone (0.64 pg/hepatocyte, range: 0.02-1.02, n = 30, p = NS). CONCLUSION: These data indicate that chronic HDV infection suppresses intrahepatic expression of HBcAg but not HbsAg and pre-S antigens, suggesting a differential effect of chronic HDV infection on HBV gene expression.     

Ultrastructural demonstration of hepatitis B virus production in a mouse model produced by hydrodynamic transfection

A mouse model of hepatitis B virus (HBV) infection produced by hydrodynamic injection of HBV DNA has been recently established. However, the ultrastructural demonstration of HBV particles in this mouse model has not as yet been reported. In our study, plasmid DNA containing wild-type HBV DNA was rapidly injected into 8-week-old female SCID mice via the tail vein. Serum levels of HBsAg were measured by ELISA kit. Intrahepatic HBV protein expression was detected by immunohistochemistry of HBcAg. Ultrastructural study of the serum samples was performed by transmission electron microscopy and immunogold electron microscopy. Serum HBsAg and intrahepatic HBcAg were detected in HBV DNA-injected mice for at least 14 days. Spherical and filamentous particles 22 nm in diameter and double-shelled Dane-like particles 42 nm in diameter were detected in the sera of mice. The ultrastructural features of these particles were identical to HBV particles observed in serum from chronic hepatitis B patients. These particles were confirmed to be HBV particles by immunogold electron microscopy. We conclude that our present HBV mouse model using hydrodynamic transfection of HBV DNA is appropriate for production of HBV virions including Dane particles. This mouse model may be useful for screening in vivo the efficacy of antiviral drugs.     

Intrahepatic expression of hepatitis B virus antigens: effect of hepatitis C virus infection.

Coinfection with hepatitis B and C viruses (HBV, HCV) is not uncommon, but the expression of HBV antigens in the liver of patients with concomitant HCV infection has not been investigated. This study aimed to evaluate the effects of concomitant HCV infection on the intrahepatic expression of HBV antigens in chronic hepatitis. HBV surface and core antigens (HBsAg, HBcAg) were immunohistochemically evaluated and semiquantitatively scored in liver biopsy specimens from patients with chronic hepatitis, comprising 17 cases with dual HBV/HCV infection and 25 with HBV infection alone. The prevalence of HBV Ag expression proved significantly lower in the group with dual infection. In the presence of active HBV replication (HBV DNA-positive serum) the prevalence of HBsAg and HBcAg immunoreaction was similar in the two groups, though a significantly lower percentage of cells expressed HBcAg in the group of coinfected patients. HBV Ag was not detected at all among HBV DNA-negative/HCV RNA-positive cases. In conclusion, these observations suggest that HCV might influence HBV antigen expression in the liver and that either partial or complete suppression might occur.     

Detection of hepatitis B virus DNA in hepatocellular carcinoma: methylation of integrated viral DNA

In order to determine whether integrated hepatitis B virus DNA sequences in primary liver tumours are methylated we have analysed tumour DNA digested with either MspI or HpaII restriction endonuclease by Southern hybridization. Our results demonstrate methylation in 11 of 17 tumour DNA samples. Where possible, we have examined the tumour tissues for expression of HBsAg and HBcAg using the indirect immunoperoxidase technique. One tumour was positive for both HBsAg and HBcAg and a second was positive for HBsAg alone. Both of these tumours were in the group in which methylation of integrated HBV DNA sequences could not be detected. We postulate that methylation of integrated HBV DNA sequences may influence HBV gene expression in hepatocellular carcinoma.     

高复制HBV转基因小鼠模型对抗乙型肝炎病毒药物的效应研究

 目的：研究高复制HBV转基因小鼠模型对抗乙肝病毒药物的效应评价。 方法： 选用抗乙肝药物拉咪呋啶、大剂量重组乙肝蛋白疫苗、α-1b型干扰素和RNA干扰在转基因小鼠进行药效及作用机制评价。 结果：拉咪呋啶、重组乙肝疫苗、α-1b型干扰素均可使HBV转基因小鼠血清中HBV DNA滴度显著降低。其中后两者还可提高机体脾细胞IL-2和IFN-γ的水平及使分泌IFN-γ脾细胞Elispot斑点数明显增加。将RNA干扰表达载体pU6-siHBV质粒尾静脉注入小鼠体内。注射后5 d血清HBsAg下降56.7%,抑制作用持续14 d。肝脏免疫组化显示HBcAg阳性细胞明显减少，但血清HBV DNA定量无明显降低。 结论： 本近交系高复制HBV转基因小鼠模型对抗乙肝药物药效学评估是可靠、可行的。     

Designing of a candidate edible vaccine against hepatitis B and HIV on the basis of a transgenic tomato

The synthetic chimeric gene TBI-HBS encoding the synthesis of immunogenic ENV and GAC epitopes of HIV-1 (immunogenes of T- and B-lymphocytes) and of the surface protein (HBsAg) of the hepatitis B virus was introduced into tomato plants var. Ventura by agrobacterial vector pBIN35TBI-HBS; transgenic tomato plants with the integrated gene TBI-HBS were generated. The integration of the TBI-HBS target gene was confirmed by PCR. The synthesis of antigenic proteins of TBI and HBsAg in fruits of transgenic tomato plants was displayed by immunoassay. The fruits of transgenic tomato plants were fed to experimental mice with a 1-week interval. On days 14 and 28, there was discovered a sufficiently high content of antibodies to the antigenic proteins of HBV and HIV-1 in serum of experimental animals. Antibodies were found in feces of experimental mice; no antibodies were found in the control group of mice. Hence, it was established that the TBI (HIV-1) and HBsAg (HBV) antigens were synthesized in transgenic tomato fruits due to the integrated construction of pBINNp35TBI-HBS in an amount that was enough to induce the immunogenic response in mice to the oral delivery of edible vaccine.