国产重组酵母乙型肝炎疫苗接种小学生的五年免疫效果观察

为了解国产重组酵母乙肝疫苗的免疫持久性,对接种2批国产酵母疫苗（5μg/Dose),1批进口酵母疫苗（A;10μg/Dose)和另1批进口酵母疫苗（M;5μg/Dose)的268名小学生,进行了免后5年（T60）效果随访观察。结果表明,T60时接种A疫苗组抗体GMT（几何平均滴度）（197．53）显著高于M疫苗组（110．66）和2批国产疫苗（9312645GMT78．48,9312623GMT56．06）。抗体阳转率A疫苗组（85．71％）显著高于M疫苗组及国产两批疫苗（61．76％、65．26％、63．83％）（P＜0．05）。而国产两批疫苗与M疫苗组无显著性差异（P＞0．05）。本次随访结果表明,虽然国产酵母疫苗免后5年的抗体阳转率和抗体GMT与剂量相同的进口酵母疫苗的水平相当,但抗体阳转率已降至70％以下,应考虑加强接种。     

乙型肝炎血源疫苗皮内接种4年效果观察

为了解乙型肝炎血源疫苗皮内接种的持久效果,选ＨＢｓＡｇ、抗－ＨＢｓ和抗－ＨＢｃ均（－）的９～１１岁儿童１０３名,随机分成４组,分别皮内接种１μｇ×４和３μｇ×４（均按０,１,２,５月程序）和肌肉接种１０μｇ×３和３０μｇ×３（各按０,１,２月程序）。首针后４８月时,１μｇ、３μｇ、１０μｇ和３０μｇ组抗－ＨＢｓ≥１０ｍＩＵ／ｍＩ者各为６９．２％,８０．０％、９２．３％和８１．８％;ＧＭＴ则为１４．５,７９．０,４４．８和７０．９ｍＩＵ／ｍｌ,３μｇ×４皮内免疫的近期和远期效果与肌肉组３０μｇ×３相似,宜于某些人群采用     

少年儿童接种乙型肝炎血源疫苗的效果评价

5～15岁的HBV易感儿童,按0、1、6月程序接种10μg×3乙型肝炎血源疫苗(北京生研所批号8615-1A、8722-2)。接种后1～2年他们的抗-HBs阳转率为～92％,无一例HBsAg阳转;未接种疫苗的对照组儿童,抗-HBs阳转率仅2.08％～2.60％,HBsAg阳转率分别为3.23％和2.08％。流行病学保护效果良好。易感少年儿童接种乙型肝炎血源疫苗将加快控制乙型肝炎的进程。     

不同批号乙型肝炎血源疫苗的免疫效果

以北京和上海生物制品研究所生产的不同批号的乙型开炎血源疫苗,免疫HBsAg和HBeAg均阳性母亲及HBsAg阴性母亲的新生儿,以及不同年龄的儿童和成人HBV易感者,程序为0、1、6个月。在第一针后9～12个月采血,用RIA法检测抗-HBs,S/N≥10.0为阳性。观察不同批号疫苗兔疫后的抗-HBs阳转率。6个批号的疫苗,以30、10、10μg和30μg×3剂量免疫HBsAg和HBeAg均阳性母亲的新生儿210人,抗-HBs阳转率为74.46％～84.09％,7个批号以10μg×3免疫阴性母亲的新主儿1510人,抗-HBs阳转率为80.29％～96.24％;3个批号以10μg×3免疫易感儿童238人,2号批号以10μg×3疫易感成年人127人,抗-HBs阳转率前者为87％～100.0％,后者为90％～96％。如按S/N≥2.1计算,抗-HBs阳转率可全部达到90％以上。提示我国生产的乙肝疫苗对各年龄人群都有较好的免疫反应,个别批号间有些差异,但经统计处理多无显著意义。     

新生儿大规模乙型肝炎血源疫苗免疫的效果考核

在上海、广东、湖南、河北四省市试点区200万人口中,每年用乙型肝炎血源疫苗免疫新生儿3万人。四省市四年平均接种率为91％～95％。除上海地区对HBsAg阳性母亲的新生儿的免疫剂量为20μg×3外,其余地区大多来用10μg×3。免疫后1至2年和3至4年期间两次考核免疫效果。免疫后3～4年检检测省市HBsAg阳性率平均为1.78％,同免疫前本底对照的16.2％相比,下降88.98％(82.68％～92.71％)。上海4岁婴儿HBsAg阳性率降至0.98％,比免疫前本底对照的9.38％降低89.57％。四年后抗HBs阳性率在67.8％～81.6％之间。本项研究表明,新生儿血源乙型肝炎疫苗普遍免疫的效果极佳。如普遍使用10μg剂量,HBsAg阳性率可从10％下降至2％～3％左右。结合其它研究结果,如对HBsAg阳性孕妇的新生儿首剂使用30μg免疫,或加用HBIg,则新一代人HBsAg阳性率将降至1％以下。     

新生儿接种10μg3针乙型肝炎血源疫苗5年内的免疫效果观察

1986～1958年,对广东3个城市1～5岁儿童乙型肝炎病毒(HBV)感染做横断面调查的基础上,给新生儿普种乙型肝炎血源疫苗。出生后24小时内接种1针,1、6个月接种第、3针,每针10μg,共接种1万余名。免疫后抽查HBsAg阳性母亲新生儿血380人份,HBsAg阴性母亲新生儿血1466人份。同时采集同期出生的未免疫的新生儿血116份作为内对照。以放射免疫法(RIA)检测HBV指在。结果,新生儿免疫后1～5年,标化抗-HBs阳转率为67.3％～79.1％。免疫后1～5年HBsAg阳性率与免前HBsAg阳性率比较,其保护率为65.8％～92.1％;与平行内对照的HBsAg阳性率比较,保护率为58.6％～88.1％。且发现HBsAg阳性母亲的新生儿,随免疫年限延长,HBsAg阳性率有降低趋向。     

乙型肝炎血源疫苗不同剂量与不同途径免疫儿童的效果比较

比较了四组乙型肝炎血源疫苗不同剂量和不同免疫途径的免疫效果。每组对象为6～7岁儿童30～50人。每人三剂疫苗,程序为 0、1和6个月。其中10μg肝注组免疫三针后1个月和3年,抗HBs阳住率均为100％;而3μg肌注组仅为78％和40％;5μg肌注组和3μg皮内接种组的抗-HBs阳性率在89％～100％之问。免疫后18个月做抗-HBs相对定量,各组mIU/ml的GMT由高到低依次为10μg肌注组、3μg皮内组、5μg肌注组和3μg肌注组。由此可见,对学龄前HBV标志阴性的儿童进行免疫,在各组中以10μg疫苗肌注效果最佳,而3μg肌注无实用价值。如考虑到疫苗费用,则5μg肌注或3μg皮内注射也不失为可取的方法。     

农村新生儿出生后3个月内开始接种三剂10μg乙型肝炎血源疫苗的免疫效果

在农村每月进行计划免疫时给新生儿接种乙型肝炎血源疫苗,剂量为10μg×3,程序为0、1、6个月,首剂免疫时间(以此为0月计算)平均在出生后1.5±1.2个月。全程接种率达92.9％。免疫儿童长到12～48月龄时HBsAg阳性率由原来的15.1％降至2.0％,保护率为86.8％。血清抗-HBs阳性率从免疫前地区本底对照的27.7％上升到87.3％,增加2.2倍。在免疫屏障的保护下,同龄未免儿童的HBsAg阳性率和HBV感染率分别下降到4.9％和16.0％,比免疫前地区本底对照低67.5％和70.4％。本研究结果表明,3针10μg乙肝疫苗于新生儿出生后1～3个月内接种仍能有效地降低HBsAg携带率,即使完全忽略了HBsAg阳性母亲的围产期传播。但必须达到很高的全程接种率。     

乙肝疫苗免疫持久性观察

本文比较10μg三个批号国产HB-Vac的4年免疫持久性,发现在同一年龄组免疫持久性在性别上无差异(P>0.05),但在临界保护率(S/N≥2.1)和有效保护率(S/N≥10)幼儿组明显高于成年组(P<0.05)。鉴于幼儿初免4年后有效保护率下降到60％以下,建议HBVac加强免疫可在初免3—4年进行。     

新生儿接种小剂量乙肝疫苗后3-5年随访观察

本文对９３８例初生婴儿接种小剂量（１０ｕｇ×３）乙肝疫苗后３－５年的预防效果进行了随访观察,并以２５３例初生儿未接种疫苗者作为对照,结果表明,接种组３－５年后抗－ＨＢｓ阳性率显著高于对照组,ＨＢｓＡｇ阳性率则较对照组显著为低。感染保护率８６．７％。结果还表明,接种乙肝疫苗３年后加强１次,比不加强者Ｐ／Ｎ均值显著增高。文章认为初生儿接种小剂量乙肝疫苗有长期免疫效果;接种后３年加强接种１次,可保持较高免疫力。     

无环鸟苷抗乙型肝炎病毒复制长短程疗法随访观察

慢性乙型肝炎病毒感染s5例,随机分无环鸟苷长程组22例,短程组11例和对照组22例。经一年随访观察,无环鸟苷治疗组见血清HBeAg、DNA-P和HBV-DNA有规律性阴转,短程组于12个月又有部分指标阳转,长程组阴转较多,其血清HBeAg、DNA-P和HBV-DNA阴转率与短程和对照组比较有显著性差异。一年结果四项病毒复制指标全部阴转例数与对照组有显著性差异,结果表明,无环鸟苷长疗程是有较好疗效。     

A Human Monoclonal Antibody against Hepatitis B Surface Antigen with Potent Neutralizing Activity

We describe the production and characterization of human monoclonal antibodies (mAb) specific for the major hepatitis B virus (HBV) S protein. The mAbs, two IgG1κ and one IgG1λ, were secreted by B-cell clones obtained from peripheral blood mononuclear cells (PBMC) of one person convalescent from acute hepatitis B and one vaccinated individual. The former recognized a denaturation-insensitive epitope within the p24 protein whereas the latter recognized a denaturation-sensitive, conformational epitope located within the HBsAg common “a” determinant. This mAb, denominated ADRI-2F3, displayed a very high protective titer of over 43,000 IU/mg mAb and showed an extremely potent neutralizing activity in the in vitro model of HBV infection using primary hepatocytes from Tupaia belangeri as target. Recombinant variable heavy and light domain sequences derived from mAb ADRI-2F3 were cloned into eukaryotic expression vectors and showed identical fine specificity and 1 log₁₀ higher titer than the original IgG1λ. It is envisaged that such mAb will be able to efficiently prevent HBV reinfection after liver transplantation for end-stage chronic HBV infection or infection after needle-stick exposure, providing an unlimited source of valuable protective anti-HBs antibody.     

反义技术在抗HBV感染中的应用

反义技术是近些年来随着现代分子生物学技术的发展而产生的新的生物医学治疗技术。它采用反义核酸分子抑制、封闭或破坏靶基因组的技术手段,包括反义寡核苷酸、核酶及RNA干扰等。反义分子通过与靶基因异性互补配对结合,阻断靶基因的复制、转录或翻译过程,从而发挥抗病毒作用。针对乙型肝炎病毒的反义技术也有了广泛而深入的研究。根据反义技术在分子、细胞以及动物水平上的研究表明：反义技术能够高效、特异地抑制HBV的复制与表达。     

Protective Efficacy of DNA Vaccines against Duck Hepatitis B Virus Infection

The efficacy of DNA vaccines encoding the duck hepatitis B virus (DHBV) pre-S/S and S proteins were tested in Pekin ducks. Plasmid pcDNA I/Amp DNA containing the DHBV pre-S/S or S genes was injected intramuscularly three times, at 3-week intervals. All pre-S/S and S-vaccinated ducks developed total anti-DHBs and specific anti-S antibodies with similar titers reaching 1/10,000 to 1/50,000 and 1/2,500 to 1/4,000, respectively, after the third vaccination. However, following virus challenge, significant differences in the rate of virus removal from the bloodstream and the presence of virus replication in the liver were found between the groups. In three of four S-vaccinated ducks, 90% of the inoculum was removed between <5 and 15 min postchallenge (p.c.) and no virus replication was detected in the liver at 4 days p.c. In contrast, in all four pre-S/S-vaccinated ducks, 90% of the inoculum was removed between 60 and 90 min p.c. and DHBsAg was detected in 10 to 40% of hepatocytes. Anti-S serum abolished virus infectivity when preincubated with DHBV before inoculation into 1-day-old ducklings and primary duck hepatocyte cultures, while anti-pre-S/S serum showed very limited capacity to neutralize virus infectivity in these two systems. Thus, although both DNA vaccines induced high titers of anti-DHBs antibodies, anti-S antibodies induced by the S-DNA construct were highly effective in neutralizing virus infectivity while similar levels of anti-S induced by the pre-S/S-DNA construct conferred only very limited protection. This phenomenon requires further clarification, particularly in light of the development of newer HBV vaccines containing pre-S proteins and a possible discrepancy between anti-HBs titers and protective efficacy.     

Hepatitis C Virus NS5B and Host Cyclophilin A Share a Common Binding Site on NS5A

Nonstructural protein 5B (NS5B) is essential for hepatitis C virus (HCV) replication as it carries the viral RNA-dependent RNA polymerase enzymatic activity. HCV replication occurs in a membrane-associated multiprotein complex in which HCV NS5A and host cyclophilin A (CypA) have been shown to be present together with the viral polymerase. We used NMR spectroscopy to perform a per residue level characterization of the molecular interactions between the unfolded domains 2 and 3 of NS5A (NS5A-D2 and NS5A-D3), CypA, and NS5B_Δ21. We show that three regions of NS5A-D2 (residues 250–262 (region A), 274–287 (region B), and 306–333 (region C)) interact with NS5B_Δ21, whereas NS5A-D3 does not. We show that both NS5B_Δ21 and CypA share a common binding site on NS5A that contains residues Pro-306 to Glu-323. No direct molecular interaction has been detected by NMR spectroscopy between HCV NS5B_Δ21 and host CypA. We show that cyclosporine A added to a sample containing NS5B_Δ21, NS5A-D2, and CypA specifically inhibits the interaction between CypA and NS5A-D2 without altering the one between NS5A-D2 and NS5B_Δ21. A high quality heteronuclear NMR spectrum of HCV NS5B_Δ21 has been obtained and was used to characterize the binding site on the polymerase of NS5A-D2. Moreover these data highlight the potential of using NMR of NS5B_Δ21 as a powerful tool to characterize in solution the interactions of the HCV polymerase with all kinds of molecules (proteins, inhibitors, RNA). This work brings new insights into the comprehension of the molecular interplay between NS5B, NS5A, and CypA, three essentials proteins for HCV replication.     

天然来源的乙型和丙型肝炎病毒抑制剂的研究进展

慢性病毒性肝炎是威胁人类健康的主要流行病之一,目前全球约有 4 亿慢性乙型和丙型肝炎患者,现有临床药物仍不能很好地治愈 病毒性肝炎。作为药物发现的重要来源,天然产物提供了许多能强效抑制乙型肝炎病毒 (hepatitis B virus, HBV) 和丙型肝炎病毒（hepatitis C virus, HCV）的抑制剂。综述近 10 年来国内外报道的抗 HBV 和 HCV 的活性中药成分和天然产物的研究进展。     

Colorimetric Assay System for Screening Antiviral Compounds against Hepatitis B Virus

A highly sensitive, rapid, and accurate assay system was developed for the in vitro evaluation of anti-hepatitis B virus (anti-HBV) agents. Chronic HBV-producing HB611 cells were used in combination with immunoaffinity purification, polymerase chain reaction (PCR), and hybrid capture detection. HB611 cells were incubated with putative anti-HBV agents for 7 days in 96-well microtiter plates. HBV was purified from HB611 cell culture media using immunoaffinity purification. The HBV DNA was extracted, amplified with PCR, and assayed using a hybrid capture colorimetric method. This assay provided quantitative detection of extracellular HBV DNA from 25 μl of cell culture media. Using the colorimetric method, we found that 50% effective concentration levels of several known anti-HBV agents (HPMPA, PMEDAP, PMEA and others) were similar to those reported in studies using Southern blot analysis. These results demonstrate that this new and easily automated colorimetric assay system can be used for the rapid and accurate assessment of anti-HBV compound selectivity.