PTD-HBcAg融合蛋白诱导特异性CTL在HepG2.2.15细胞抑制HBV复制的研究

目的探讨PTD-HBcAg融合蛋白诱导小鼠体内特异性CTL并抑制HepG2.2.15细胞HBV复制的作用。方法 PTD-HBcAg、HBcAg和阴性对照分别与等体积的弗氏佐剂乳化后皮下免疫小鼠;第14d,分离脾淋巴细胞并分别用PTD-HBcAg、HBcAg、PTD和PBS加强刺激后收集上清,检测细胞因子IFN-γ、IL-12、IL-4和IL-10;刺激后的淋巴细胞作为效应细胞与HepG2.2.15细胞共培养,检测,效应细胞对HBsAg、HBVDNA的抑制作用及对HepG2.2.15细胞、HepG2细胞的杀伤效果。结果 PTD-HBcAg组分泌的IFN-γ、IL-12、IL-4和IL-10与HBcAg组和阴性对照组比较差异有统计学意义(P0.05);PTD-HBcAg融合蛋白组较HBcAg组和阴性对照组有更明显的病毒抑制作用(P0.05);PTD-HBcAg组对HepG2.2.15细胞的杀伤率明显高于HBcAg组和阴性对照组(P0.05)。结论 PTD-HBcAg可诱导HBV特异性CTL,能有效抑制HepG2.2.15细胞HBV的复制。     

聚合酶RNA干扰对小鼠体内乙型肝炎病毒的抑制作用

目的:利用流体动力学法构建小鼠HBV感染模型,观察pSiHBV/P在体内对HBV的抑制作用.方法:以流体动力学法构建小鼠HBV感染模型,将pSiHBV/P与pHBV1.3尾静脉共注射Balb/c小鼠.转染后第6天,用酶联免疫分析法检测小鼠血清乙肝表面抗原(HBsAg),用荧光定量PCR检测血清HBV DNA的水平,用免疫组织化学方法检测肝内HBsAg、乙肝病毒核心抗原(HBcAg)的表达,RT-PCR法半定量检测肝内HBV 3.5 kb mRNA、S-mRNA及0.7 kb mRNA的水平.结果:感染组和无关干扰组血清HBsAg表达量平均值分别为9.11±3.34和8.19±5.41,pSiHBV/P干扰组平均值1.94±1.78;pSiHBV/P干扰组血清中HBV DNA的含量较感染组明显下降(2.91±0.55 vs 4.32±0.57,P<0.05),抑制率为33%;干扰组肝细胞中HBsAg和HBcAg阳性细胞数较对照组明显减少;干扰组3.5 kbmRNA、S-mRNA的水平较感染组和无关干扰组均有明显下降(0.48±0.19 vs 1.06±0.40,0.88±0.54;0.46±0.18 vs 1.05±0.38.0.90±0.51,P<0.05).结论:RNAi技术在体内能高效、特异地抑制小鼠体内HBV.     

胞质转导肽-HBcAg18-27-Tapasin通过激活PI3K/Akt通路抑制HBV转基因小鼠特异性CTL凋亡

目的探讨胞质转导肽(CTP)-HBcAg18-27-Tapasin融合蛋白通过激活PI3K/Akt信号通路抑制HBV转基因小鼠特异性细胞毒性T淋巴细胞(cytotoxic T cell,CTL)凋亡。方法 HBV转基因小鼠随机分组,100μg CTP-HBcAg18-27-Tapasin、50μg CTPHBcAg18-27-Tapasin、50μg CTP-HBcAg18-27及生理盐水组经肌肉免疫小鼠,每周一次,共3次。流式细胞仪检测脾细胞中胞内细胞因子水平及细胞凋亡率,Western blotting检测凋亡相关蛋白PI3K、P-Akt及P-mTOR表达的变化。结果 100μg CTP-HBcAg18-27-Tapasin融合蛋白免疫转基因小鼠后,能有效上调特异性CTL数量(2.74±0.20)%,高于对照组50μg CTP-HBcAg-18-27-Tapasin(2.42±0.53)%及50μg CTP-HBcAg18-27(1.70±0.56)%和空白组(0.66±0.71)%(F=741.45,P=0.000);同时,100μg CTPHBcAg18-27-Tapasin融合蛋白有效抑制特异性CTL凋亡(6.29±0.02)%,低于对照组50μg CTP-HBcAg18-27-Tapasin(7.72±0.15)%及50μg CTP-HBcAg18-27(26.30±1.13)%和空白组(58.26±0.23)%(F=5313,P=0.000),并伴随凋亡相关蛋白PI3K、P-Akt及P-mTOR上调(F=52.61、18.32和94.18,P0.05)。结论 CTP-HBcAg18-27-Tapasin能有效诱导HBV转基因小鼠特异性CTL的表达,抑制其凋亡,机制与PI3K/Akt通路的激活有关。     

HBsAg基因修饰的树突状细胞诱导HBV转基因小鼠的免疫应答

目的探讨HBsAg重组腺病毒Ad—S转染的小鼠树突状细胞（DC）诱导HBV转基因（Tg）小鼠免疫应答的作用特点及其可能的治疗作用。方法Tg小鼠的骨髓细胞体外扩增为DC，转染Ad—S或被HBsAg蛋白冲击后，与pcDNA3．1（＋）-S质粒分别免疫Tg鼠，用流式细胞术、乳酸脱氢酶释放法、酶联免疫分析（ELISA），荧光定量聚合酶链反应（PCR）等分别检测脾脏T细胞内细胞因子和细胞毒性T淋巴细胞（CTL）活性、血清HBsAg，抗-HBs、HBVDNA及丙氨酸转氨酶（ALT）水平；病理和免疫组化分析肝脏组织学及HBsAg和HBcAg表达。结果免疫后1～2周，DC／Ad-S比DC／HBsAg和pcDNA3．1（＋）-S诱导rrc分泌干扰素7（IFN-g）和特异性CTL均显著增强，而DC／HBsAg组CTL较pcDNA3．1（＋）-S组增强（P〈0．05）；DC／HBsAg免疫后1、2、4周CTL迅速减弱，DC／Ad-S在1、2周CTL差异不明显，但至4周时明显减弱。免疫后1～4周，对Tg鼠血清HBsAg、HBVDNA及肝组织HBcAg和HBsAg表达的抑制作用最强为DC／Ad-S免疫，其次为DC／HBsAg，显著强于pcDNA3．1（＋）-S（P〈0．05或P〈0．01）。肝脏组织学、血清抗-HBs和ALT水平各组差异无统计学意义。结论Ad—S转染的DC比HBsAg冲击的DC和DNA疫苗诱导更强的Tcl和CTL应答，能较迅速抑制HBV转基因小鼠血清HBsAg、HBVDNA和肝脏HBcAg和HBsAg表达。     

急性乙型肝炎患者特异性核心抗原细胞毒性T淋巴细胞频率的变化及其意义

目的 动态观察急性乙型肝炎(AHB)患者外周血HBcAg18-27表位特异性细胞毒性T淋巴细胞(CTL)、血清ALT、HBV DNA、HBsAg和淋巴细胞亚群的变化,探讨HBV特异性CTL频率的消长在病毒清除以及肝脏损伤中的作用.方法 分别选取AHB、慢性乙型肝炎(CHB)患者外周血,根据人类白细胞抗原(HLA)-A0201结果分为两组:HLA-A0201阳性患者作为HBV特异性CTL检测组、HLA-A0201阴性患者作为特异性抗原表位对照组.用HLA-A0201限制性表位HBcAg18-27五聚体复合物通过流式细胞技术,动态定量检测外周血中HBV特异性CTL频率和T、B淋巴细胞与自然杀伤细胞(NK)和NKT淋巴细胞;以速率法检测血清ALT水平;荧光定量PCR检测HBV DNA水平; Abbott微粒子化学发光技术检测HBV血清学标志物.计量资料采用均数±标准差((x)±s)表示或中位数(P25-P75)描述,组间比较采用方差分析或非参数检验(KruskalWallis检验和Mann-Whitney U检验);两种计量指标的关系采用Pearson相关分析.结果 AHB患者入院第1、2、3周外周血HBcAg表位特异性CTL频率分别为2.11%(0.20%～3.64%)、3.56%(1.05%～5.91%)、2.03%(0.33%～3.58%),高于入院第4、5、6周的0.99%(0.12%～2.16%)、0.29%(0.05%～0.76%)、0.39%(0.05%～0.46%),也显著高于CHB的0.11%(0.06%～0.29%),z值分别为-3.258,-4.041,-3.259,P值均＜0.01.AHB患者HBcAg表位特异性CTL峰值延迟于血清HBV DNA、HBsAg和ALT等指标的峰值;在AHB患者中,HBcAg表位特异性CTL高频率患者的血清HBsAg消失时间早于CTL频率较低的患者[(1.75±1.04)周与(4.33±3.51)周,t=-2.018,P＜0.05].CD3+CD8+T淋巴细胞频率的峰值出现在入院后第2周,并与HBcAg表位特异性CTL峰值相重叠,两者动态变化规律呈相关性(r=0.420,P＜0.01).AHB患者早期外周血NK、NKT淋巴细胞数量显著低于正常对照组和CHB患者,但随着病情好转而逐渐恢复,AHB患者外周血NK细胞数量变化与HBcAg特异性CTL动态变化呈负相关(r=-0.435,P＜0.01).结论 急性HBV感染者高频率的HBcAg表位特异性CTL与HBsAg的更早消失有密切关系,动态监测外周血中HBcAg特异性CTL频率变化,可以作为预测HBV感染后临床转归的参考指标;AHB患者外周血CD8+T淋巴细胞数量的变化,可以间接反应AHB患者体内HBcAg特异性CTL频率的改变.

Abstract：

Objective This report aims to investigate the dynamical changes of HBcAg18-27 epitope specific cytotoxic T lymphocytes(CTL), alanine aminotransferase (ALT), HBV DNA and HBsAg in peripheral blood of acute hepatitis B patients, and to explore the roles of HBcAg18-27-specific CTLs in virus clearance and liver injury. Methods Acute hepatitis B (AHB) and chronic hepatitis B (CHB) patients were divided into two groups according to results of HLA-A0201. Patients with positive HLA-A0201 were classified into HBcAg-specific CTL group and those with negative HLA-A0201 were referred as control group.The specific CTLs were stained with HLA-A0201 limited HBcAg18-27 epitope MHC-Pentamer and the frequencies of CTLs, T, B, NK and NKT cells were detected by flow cytometry (FCM). The serum ALT, HBV DNA and HBsAg were examined using speed analysis, quantitative PCR and abbott chemiluminescent technology. Results The frequencies of HBcAg18-27-specific CTLs in AHB patients were higher in the early three weeks as compared to the late three weeks. The apex time of HBV-specific CTL frequencies lagged behind those of HBV DNA, HBsAg and ALT. The loss of HBsAg in patients with high frequencies of HBVspecific CTL was earlier than that in patients with low frequencies (t = 2.018, P ＜ 0.05). In the second week the peak frequencies of CD3+CD8+ cells overlapped with that of HBcAg18-27-specific CTLs and with a positive correlation between (r = 0.420, P ＜ 0.05). During the early stages of AHB, the frequencies of NK and NKT cells were found significantly lower than that of control group and CHB group and the levels were back to normal after recovery. Moreover, a negative correlation existed between the frequencies of NK cells and the dynamic changes of HBcAg18-27-specific CTLs (r = -0.435, P ＜ 0.01) in AHB group. The frequencies of HBcAg18-27-specific CTLs were significantly higher as compared to CHB group in the first three weeks (z = -3.258, -4.04, and -3.259, P ＜ 0.01). Conclusion The early loss of HBsAg was closely related to the high frequencies of HBcAg18-27 specific CTLs in AHB patients. HBcAg-specific CTL frequencies in peripheral blood could be used to predict clinical outcome after HBV infection. The frequencie of CD8+ T cells can reflect the changes of frequencies of HBcAg-specific CTL. during acute HBV infection.     

HBeAg阴性慢性乙型肝炎病毒感染者肝组织病理改变的相关因素分析

目的 分析HBeAg阴性慢性HBV感染者肝组织病理改变的相关因素.方法 对288例不同年龄、性别、ALT水平、肝组织HBsAg和HBcAg免疫组织化学结果的HBeAg阴性HBV感染者的HBV DNA载量、肝组织病理变化进行相关分析,采用Bivariate Pearson法.结果 男性组肝组织炎症分级和纤维化分期分别为1.721.23和1.71±1.24,女性组分别为1.25±1.39和1.21±1.40,两组差异有统计学意义(t=2.398,t=2.551;均P＜0.05)}男性HBV DNA载量高于女性,但差异无统计学意义.40岁以上HBeAg阴性HBV感染者HBV DNA载量、肝组织炎症分级和纤维化分期显著高于40岁以下者(t=2.060,t=2.536,t=2.808;均P＜0.05).ALT正常的HBeAg阴性乙型肝炎患者中,75例(52.03%)血清HBVDNA≤1×103拷贝/mL,肝组织炎症活动度≥G2的56例,占38.89%,血清ALT水平与肝组织炎症活动度相关(r=0.244,P=0.004).ALT异常的慢性HBV感染者中,42例(31.57%)血清HBV DNA≤1×103拷贝/mL,肝组织炎症活动度≥G2的89例,占66.92%.血清ALT水平与肝组织炎症程度无相关(r=0.007,P=0.939).肝组织免疫组织化学HBsAg及HBcAg双阳性组肝组织炎症/纤维化、HBV DNA滴度显著高于HBsAg、HBcAg双阴性组和HBsAg阳性、HBcAg阴性组,差异有统计学意义.血清HBV DNA与肝组织炎症程度相关(r=0.349,P＜0.05).结论 性别、年龄、血清HBV DNA水平及HBsAg、HBcAg免疫组织化学结果可作为判断HBeAg阴性慢性乙型肝炎患者肝组织炎症损伤程度的相关指标,男性、年龄越大、血清HBV DNA水平越高、肝组织免疫组织化学HBsAg及HBcAg双阳性,肝组织炎性反应损伤越严重.HBeAg阴性慢性乙型肝炎患者即使ALT正常、血清HBV DNA≤1×100拷贝/mL,仍约1/3患者的肝组织存在明显的炎性反应损伤,需定期追踪,最好行肝组织活检,以早期发现适宜治疗者而避免延误病情.     

HBsAg和HBcAg融合表达质粒对HBV转基因小鼠的体液免疫治疗效应

目的观察融合表达质粒pcDNA3．1-SC对HBV复制和表达的抑制效果。方法 构建融合表达质粒pcDNA3．1-SC，以100μg肌肉接种C57，BL／6 HBV DNA转基因小鼠，2、4周后各加强免疫1次。然后动态检测小鼠血清抗-HBs、抗-HBc的诱生，以及肝组织HBsAg、HBcAg和血清HBV DNA的消长情况。结果接种后4、8、12周，小鼠血清抗-HBs阳转率分别达到55％、67％和33％；而抗-HBc阳转率低于20％；同时，与接种前相比，肝组织内HBsAg、HBcAg表达和血清HBV DNA水平呈逐渐减弱的趋势，在接种后8周，有1／3的小鼠已不能检出。结论融合表达质粒pcD—NA3．1-SC能够在一定程度上抑制转基因小鼠体内的HBV DNA复制和抗原表达，提示了研制乙型肝炎治疗性DNA疫苗的可能性。     

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.     

胎盘滋养层细胞的感染和凋亡与HBV的宫内传播机制

目的:通过HBV感染体外培养的人绒毛膜滋养层细胞,探讨HBV宫内感染发生的机制.方法:对人早孕绒毛膜滋养层细胞进行原代培养和对人滋养层细胞系JEG-3进行传代培养,将HBV感染血清与原代及传代培养细胞共同孵育8-48h,倒置显微镜观察细胞形态及细胞间连接,细胞免疫荧光和免疫组织化学染色方法检测滋养层细胞中HBsAg和HBcAg的表达,荧光定量PCR方法检测被感染的滋养层细胞中的HBV DNA,TUNEL方法检测滋养层细胞的凋亡.结果:与HBV阳性血清共同孵育对滋养层细胞的形态和细胞间连接无明显影响;细胞免疫荧光和免疫组织化学染色结果显示,滋养层细胞与HBV感染血清共同孵育(8,24,48h)后,滋养层细胞可以出现HBsAg和HBcAg的阳性表达,24 h时HBsAg阳性细胞数量最多(8h:18.0%±3.67%;24h:30.6%±2.88%;48 h:24.8%±4.21%);荧光定量PCR方法检测到被感染的滋养层细胞中HBV DNA的存在;TUNEL结果显示,与HBV感染血清共同孵育可导致滋养层凋亡细胞数量逐渐增加(24h:18.6%±3.05%;48h:26.8%±2.86%:P<0.01).结论:滋养层细胞的感染可能是HBV通过胎盘屏障的途径之一;HBV感染可以诱导滋养层细胞产生凋亡,这可能是胎盘屏障阻止HBV宫内感染的一种保护性机制.     

基于MAVS介导信号通路的补肾方抗炎抗HBV作用及机制研究

目的:观察补肾方对刀豆蛋白A(ConA)诱导HBV转基因小鼠肝损伤的抗炎及抗HBV作用机制。方法:24只HBV转基因小鼠随机分为3组,模型组及补肾方组小鼠按照体重予以3μg/g ConA尾静脉注射,正常组予以相应量生理盐水,每周1次,连续4周。造模后,补肾方组小鼠予以补肾方汤剂2.25g/kg体重灌胃,正常组及模型组小鼠予以等量生理盐水,每天1次,连续4周。观察各组小鼠处理前后血清丙氨酸转移酶(ALT)、天冬氨酸转移酶(AST)、乙型肝炎病毒表面抗原(HBsAg)、乙肝肝炎病毒脱氧核糖核酸(HBV DNA)水平及肝组织病理变化,观察各组小鼠处理前后肝组织HBcAg表达及肝组织线粒体抗病毒蛋白(MAVS)介导信号通路关键蛋白表达。结果:补肾方可显著降低ConA诱导HBV转基因小鼠血清ALT、AST水平(P0.01),减轻肝组织内炎性细胞的浸润及肝细胞的变性坏死;可显著降低小鼠血清HBsAg水平(P0.05),降低肝组织内HBcAg的表达(P0.001);可显著提高小鼠血清IFN-β水平(P0.01),上调TBK-1、STING、pTAK-1(t183)的表达,下调TRADD的表达(P0.05)。结论:补肾方具有减轻肝组织炎症、抗HBV作用,其作用机制与MAVS介导的信号通路有关。     

The hepatitis B virus

Of all the hepatotropic viruses, HBV is associated with the greatest worldwide morbidity and mortality. This is because of the ease of transmission and the potential for progression to a chronic infective carrier state, with the complications of cirrhosis and hepatocellular carcinoma. The use of PCR has shown that some of the earlier concepts concerning the interpretation of serological data were inaccurate. Many patients with anti-HBe and anti-HBs have viral DNA detectable by PCR, and some hepatocellular carcinoma patients have detectable HBV DNA in their livers in the absence of all serological markers of HBV disease. The clearance of HBV infected cells from the liver is dependent on the interplay between the interferon system and the cellular limb of the host immune response. The importance of the nucleocapsid proteins as targets for sensitized cytotoxic T cells has been established for chronic HBV infection. The importance of pre-S sequences as inducers and targets of the virus-neutralizing humoral immune response is becoming established, but their precise role must await the development of in vitro models of hepadnavirus infection and a greater understanding of the mechanisms of viral uptake. The epidemiology and clinical course of the disease can be modified by immunization, immune stimulation and antiviral chemotherapy. For the developing world, a programme of immunization at birth would be the most effective way of eliminating this disease, but at present the cost is prohibitive. For the developed world, immunization is realistic for the at-risk population, and anti-viral and immunostimulatory therapy available for those already infected. In adult acquired chronic HBV infection alpha-interferon produces HBe antigen clearance in 40-60% of cases and is followed by resolution of the hepatic inflammation. Results in neonatally acquired infection are less impressive and prednisolone priming followed by interferon may be needed. The presence of a mutation in the pre-core region of some virus isolates has recently been described. Hepatocytes infected with this virus cannot produce HBe antigen and the course of the liver disease is fairly rapid. Whether this mutant causes liver damage in the same way as the wild virus or is directly cytopathic remains unclear, and its relationship to fulminant hepatitis is under investigation.     

Hepatitis B virus taxonomy and hepatitis B virus genotypes

Hepatitis B virus (HBV) is a member of the hepadnavirus family. Hepadnaviruses can be found in both mammals (orthohepadnaviruses) and birds (avihepadnaviruses).The genetic variability of HBV is very high. There are eight genotypes of HBV and three clades of HBV isolates from apes that appear to be additional genotypes of HBV. Most genotypes are now divided into subgenotypes with distinct virological and epidemiological properties. In addition, recombination among HBV genotypes increases the variability of HBV. This review summarises current knowledge of the epidemiology of genetic variability in hepadnaviruses and, due to rapid progress in the field,updates several recent reviews on HBV genotypes and subgenotypes.     

Persistence of hepatitis B virus DNA after serological clearance of hepatitis B virus

Using Southern blot technique, the state of hepatitis B virus (HBV) DNA in liver tissue was investigated in 16 patients who were sero-negative for hepatitis B surface antigen (HBsAg) but positive for its antibody (anti-HBs). In only one case, was HBV DNA found in liver tissue in a heterogeneously integrated form. In this case, digestion with Taq I demonstrated integrated HBV DNA as two definite bands at 1.8 and 0.5 kbp. This suggests that HBV DNA in some cases persists even after HBV infection has been cleared serologically. It is possible that this persistence of HBV DNA plays an important role in hepatocarcinogenesis.     

Dual chronic hepatitis B virus and hepatitis C virus infection

Dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are common in HBV or HCV endemic areas. However, several clinical and pathogenetic issues remain unresolved. First, clinical and in vitro studies suggest the interactions between two viruses. The dynamics of the interaction in untreated setting versus treated setting and its influence on the long-term outcomes await further studies. A key issue regarding viral interactions is whether modulation of infection occurs in the same dually infected individual hepatocyte of the liver. Clarifying this issue may help to understand the reciprocal interference between HCV and HBV and provide clues for future immunopathogenetic studies. Second, the prevalence and clinical significance of coexisting occult HBV infection in patients with chronic HCV infection need further investigations. Third, combination therapy of peginterferon alfa-2a and ribavirin appears to be just as effective and safe for the treatment of hepatitis B surface antigen (HBsAg)-positive patients chronically infected with active chronic hepatitis C as it is in patients with HCV monoinfection. Nevertheless, one-third of dually infected patients with nondetectable serum HBV DNA-level pretreatment developed HBV reactivation posttreatment. How to prevent and treat this reactivation should be clarified. Furthermore, about 10% of the dually infected patients lost HBsAg. Underlying mechanisms await further investigations. Finally, the optimal treatment strategies for dually infected patients with hepatitis B e antigen-positive chronic hepatitis B should be identified in future clinical trials.     

Serum hepatitis B virus DNA in acute hepatitis type B

Sera obtained within 7 days after clinical onset of acute hepatitis type B were positive for hepatitis B virus (HBV) DNA by spot hybridization only in 4 out of 45 patients who subsequently recovered, but in 10 out of 10 patients who instead developed chronic infection. These results indicate that in uncomplicated acute hepatitis B, virus replication is limited to an early phase of infection, often preceding the onset of clinical symptoms, and suggest that serum HBV-DNA may represent an early and predictive marker of chronicity.     

Hepatitis B virus genotypes and hepatitis B surface antigen mutations in family contacts of hepatitis B virus infected patients with occult hepatitis B virus infection

Background:  The association and profile of surface gene mutations with viral genotypes have been studied in patients with chronic hepatitis B virus (HBV) but not in subjects with occult HBV infection.
Aim:  This study aimed to investigate the association of surface gene mutations with viral genotypes in occult HBV infection.
Materials & Methods:  Of 293 family contacts of 90 chronic HBV index patients, 110 consented for the study. Of 110 subjects, 97 were hepatitis B surface antigen (HBsAg) negative. HBV genotyping was done using direct DNA sequencing. The S-gene was also sequenced in 13 chronic hepatitis B patients to serve as controls.
Results:  Twenty-eight (28.8%) of the 97 subjects had occult HBV infection. Bidirectional sequencing of partial S-gene was successful in 13 of them. Seven (53.8%) of the viral sequences are genotype A1, two (15.3%) each having genotypes D5&D2 and one each (7.6%) having D1&G genotypes. Seven (53.8%) of the 13 HBsAg positive patients, had genotype D&6 (46.1%) genotype A. A128V & T143M mutations were observed in 5 of 13 (38.4%) subjects and A128V & P127S in 2 of 13 (15.3%) patients ( P  = 0.385). A128V mutation was seen in two (15.3%) subjects with D2 genotype, while T143M mutation was seen in three (23.07%) subjects with A1genotype. At aa125, three (23.07%) subjects with D5 genotype had methionine instead of threonine. There were wild type sequences in five (38.4%) subjects, one each of D1, G genotypes (20%) and four A1 (80%) genotypes. None of the subjects had G145R mutation.
Conclusions:  Occult HBV infection may be common in household contacts of chronic HBV infected patients. Equal prevalence of A&D sub-genotypes was present in occult HBV subjects and in chronic HBV patients. Mutations of the S-gene are genotype specific in both occult as well as chronic HBV infection.     

乙型肝炎病毒的传播

乙型病毒性肝炎(hepatitisbvirus,HBV),简称乙肝,在甲、乙、丙、丁、戊型肝炎中最为严重的一种.他一直是我国“八五”、“九五”、“十五”重点医疗科研攻关项目.众所周知,乙肝危害已成为一种严重的世界性疾病,全球大约有20多亿人感染过HBV,其中约有4亿人为慢性感染.WHO已将HBV感染列为世界第九死亡原因,每年全世界死亡人数约30万.我国是HBV感染高发区,有50-70%的人感染过HBV,约有1.7亿人(占全国人口的十分之一还要多)是HBsAg携带者.我国现患乙肝者约3000万,其中60%以上为慢性乙肝患者.可见乙肝患病者之多,对人类危害之大.为了让人们了解乙肝,本文从HBV的感染,发病、转归(慢性乙肝,肝硬化、肝癌)和药物治疗进行系统的介绍和讨论.     

Myocarditis and hepatitis B virus

Two patients with hepatitis B virus infection and myocarditis are reported. The implicated pathogenesis was an immune complex mechanism in one patient. Both patients presented with heart failure and arrhythmia which were controlled with conventional medical therapy. Echocardiography played an important role for early detection of left ventricular dysfunction. The efficacy and safety of corticosteroid therapy is still conjectural. Acute hepatitis B infection should be a differential diagnostic consideration in the etiology of acute myocarditis.     

Occult hepatitis B virus infection

Occult hepatitis B virus(HBV)infection(OBI)refers to the presence of HBV DNA in the absence of detectable hepatitis B surface antigen.Since OBI was first described in the late 1970s,there has been increasing interest in this topic.The prevalence of OBI varies according to the different endemicity of HBV infection,cohort characteristics,and sensitivity and specificity of the methods used for detection.Although the exact mechanism of OBI has not been proved,intrahepatic persistence of viral covalently closed circular DNA under the host’s strong immune suppression of HBV replication and gene expression seems to be a cause.OBI has important clinical significance in several conditions.First,OBI can be transmitted through transfusion,organ transplantation including orthotopic liver transplantation,or hemodialysis.Donor screening before blood transfusion,prophylaxis for high-risk organ transplantation recipients,and dialysis-specific infection-control programs should be considered to reduce the risk of transmission.Second,OBI may reactivate and cause acute hepatitis in immunocompromised patients or those receiving chemotherapy.Close HBV DNA monitoring and timely antiviral treatment canprevent HBV reactivation and consequent clinical deterioration.Third,OBI may contribute to the progression of hepatic fibrosis in patients with chronic liver disease including hepatitis C.Finally,OBI seems to be a risk factor for hepatocellular carcinoma by its direct protooncogenic effect and by indirectly causing persistent hepatic inflammation and fibrosis.However,this needs further investigation.We review published reports in the literature to gain an overview of the status of OBI and emphasize the clinical importance of OBI.     

Occult hepatitis B virus infection

Many studies have shown that hepatitis B virus infection may also occur in hepatitis B surface antigen-negative patients. This occult infection has been identified both in patients with cryptogenic liver disease and in patients with hepatitis C virus-related chronic hepatitis, and much evidence suggests that it may be a risk factor of hepatocellular carcinoma development. However, several aspects of this occult infection remain unclear, such as its prevalence and the factor(s) involved in the lack of circulating hepatitis B surface antigen. Moreover, it is uncertain whether the occult hepatitis B virus infection may contribute to chronic liver damage, considering that it is usually associated with a suppressed viral replication. Evidence and hypotheses concerning this fascinating field of biomedical research are reviewed.