Human monoclonal antibody combination against SARS coronavirus: synergy and coverage of escape mutants.
Human monoclonal antibody combination against SARS coronavirus: synergy and coverage of escape mutants.
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DOI：
10.1371/journal.pmed.0030237
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发表时间：
2006-07
期刊：
影响因子：
15.8
通讯作者：
Goudsmit, Jaap
中科院分区：
文献类型：
--
作者：
ter Meulen, Jan;van den Brink, Edward N.;Poon, Leo L. M.;Marissen, Wilfred E.;Leung, Cynthia S. W.;Cox, Freek;Cheung, Chung Y.;Bakker, Arjen Q.;Bogaards, Johannes A.;van Deventer, Els;Preiser, Wolfgang;Doerr, Hans Wilhelm;Chow, Vincent T.;de Kruif, John;Peiris, Joseph S. M.;Goudsmit, Jaap
实验动物数据表明，人单克隆抗体（mab）对严重急性呼吸综合征冠状病毒（SARS-CoV）感染具有保护作用。为了在人类中进行有效的免疫预防，需要广泛覆盖不同的SARS-CoV菌株并控制潜在的中和逃逸变体。病毒中和、非竞争单克隆抗体的组合可能具有这些特性。人单抗CR3014已被证明能完全预防感染雪貂的肺部病理并消除sars冠状病毒的咽部脱落。我们在体外产生了逃避CR3014中和的SARS-CoV变体，这些变体在逃逸病毒的糖蛋白尖峰(S)中都有一个P462L突变。体外实验证实，CR3014与含有该突变的重组S片段（氨基酸残基318-510）的结合被消除。因此，我们从SARS恢复期患者的血液中筛选抗体-噬菌体文库，寻找与CR3014互补的抗体。发现了一种新的单克隆抗体CR3022，它中和了CR3014逃逸病毒，不与CR3014竞争结合重组S1片段，并且与来自果子狸sars - cov样菌株SZ3的S1片段结合。CR3022不能生成转义变体。这两种单克隆抗体的混合物通过识别受体结合域上的不同表位，以协同方式中和SARS-CoV。100%中和时，CR3014和CR3022的剂量减少指数分别为4.5和20.5。由于关注亚中和抗体浓度对SARS-CoV感染的增强作用，我们在此表明抗SARS-CoV抗体不会将SARS-CoV原代人巨噬细胞的流产感染转化为产生性感染。两种非竞争的人单克隆抗体CR3014和CR3022的组合可能控制免疫逃逸并扩展保护的广度。同时，CR3014和CR3022之间的协同作用可以降低被动免疫预防sars冠状病毒感染的总抗体剂量。2002年底，严重急性呼吸系统综合症（SARS）在中国广东省出现。2003年2月，该省一名受感染的医生将这种对人类健康构成威胁的新病毒带到香港。在这里，住在同一家酒店的人感染了这种疾病，并把它带到其他国家。SARS在移动，搭上了国际旅行者的便车。由于导致sars - sars - cov的病毒通过密切的人际接触传播，并导致10%的感染者死亡，卫生专家担心这是一场全球性的流行病。世界卫生组织发布了全球警报，警告人们不要不必要地前往受影响地区，公共卫生官员隔离了患者及其密切接触者，从而避免了这种情况。到2003年7月，第一次SARS疫情结束了。8098人被感染；774人死亡。自那时起，SARS的散发个案已在本地得到控制。SARS的第一次流行是由一种动物病毒引起的，这种病毒已经适应了在人与人之间传播。没有理由不重复这个过程。如果是这样，严格的隔离措施可以再次防止全球流行病，但要付出相当大的经济代价。我们需要的是一种方法来防止SARS在接触过SARS冠状病毒的健康人群中发展，并治疗病人，使他们的传染性降低，从而能够对抗病毒。在这项研究中，研究人员一直在研究“被动免疫”作为限制SARS流行的一种方法。在被动免疫中，对疾病的短期保护是通过注射抗体来实现的。抗体是一种蛋白质，可以识别细菌和病毒等外来生物体上的特定分子（称为抗原），并防止这些生物体引起疾病。被动免疫的抗体可以从SARS患者的血液中分离出来，也可以在实验室中制造出所谓的“人类单克隆抗体”。其中一种人类单克隆抗体cr3014已被制成，并被证明可以预防感染sars冠状病毒的雪貂的肺损伤，并阻止被感染的动物传染给其他动物。但要有效预防人类疾病，单一的单克隆抗体可能还不够。有些sars冠状病毒的毒株是CR3014不能识别的，因此不能对其采取行动。此外，当CR3014在低抗体浓度下生长时，病毒可以改变CR3014识别的抗原，产生所谓的逃逸变体；如果发生这种情况，CR3014就不能再阻止这些逃逸变体杀死人类细胞。研究人员测试了两种单克隆抗体的组合如何很好地控制sars冠状病毒杀死人类细胞。首先，他们发现CR3014逃逸变体在与人类细胞相互作用的病毒表面部分都有相同的微小变化。CR3014在亲本SARS-CoV株中阻断了这种相互作用，但在逃逸变体中没有。然后，他们制造了一种新的单克隆抗体cr3022，它可以阻止母体SARS-CoV染色剂和CR3014逃逸病毒杀死人类细胞。这两种抗体结合到病毒表面邻近的部分，它们可以同时结合。CR3022还能结合CR3014不能结合的sars冠状病毒株的表面。当他们尝试时，研究人员无法产生任何CR3022无法结合的病毒逃逸变体。最后，两种抗体共同作用对SARS-CoV杀伤人细胞的抑制作用大于其单独作用的总和。两种（或更多）人类单克隆抗体的组合可以识别SARS-CoV表面与人类细胞相互作用的不同部分，这可能是一种让人们被动免疫SARS-CoV的好方法。它可以最大限度地减少产生逃逸变异的可能性，扩大提供保护的病毒株的范围，并减少有效保护所需的抗体数量。在对人体进行试验之前，必须先在动物身上进行试验——在培养皿中对人类细胞进行的实验结果并不总是能在整个动物或人身上得到复制。如果该方法通过进一步的测试，希望对SARS患者及其密切接触者进行被动免疫接种，可能会降低感染者的疾病严重程度，并减少病毒传播，就像采取大规模隔离措施一样有效。请通过以下摘要的在线版本访问这些网站：http://dx.doi.org/10.1371/journal.pmed.0030237。•关于SARS的Medline Plus页面•美国疾病控制和预防中心关于SARS的信息•美国国家过敏和传染病研究所关于SARS研究的概况介绍•关于SARS和单克隆抗体的维基百科页面(注：（维基百科是一个免费的在线百科全书，任何人都可以编辑）结合病毒糖蛋白刺突不同部分的两种人类单克隆抗体在体外的病毒中和和抑制耐药病毒的出现中显示出协同效应。
Experimental animal data show that protection against severe acute respiratory syndrome coronavirus (SARS-CoV) infection with human monoclonal antibodies (mAbs) is feasible. For an effective immune prophylaxis in humans, broad coverage of different strains of SARS-CoV and control of potential neutralization escape variants will be required. Combinations of virus-neutralizing, noncompeting mAbs may have these properties. Human mAb CR3014 has been shown to completely prevent lung pathology and abolish pharyngeal shedding of SARS-CoV in infected ferrets. We generated in vitro SARS-CoV variants escaping neutralization by CR3014, which all had a single P462L mutation in the glycoprotein spike (S) of the escape virus. In vitro experiments confirmed that binding of CR3014 to a recombinant S fragment (amino acid residues 318–510) harboring this mutation was abolished. We therefore screened an antibody-phage library derived from blood of a convalescent SARS patient for antibodies complementary to CR3014. A novel mAb, CR3022, was identified that neutralized CR3014 escape viruses, did not compete with CR3014 for binding to recombinant S1 fragments, and bound to S1 fragments derived from the civet cat SARS-CoV-like strain SZ3. No escape variants could be generated with CR3022. The mixture of both mAbs showed neutralization of SARS-CoV in a synergistic fashion by recognizing different epitopes on the receptor-binding domain. Dose reduction indices of 4.5 and 20.5 were observed for CR3014 and CR3022, respectively, at 100% neutralization. Because enhancement of SARS-CoV infection by subneutralizing antibody concentrations is of concern, we show here that anti-SARS-CoV antibodies do not convert the abortive infection of primary human macrophages by SARS-CoV into a productive one. The combination of two noncompeting human mAbs CR3014 and CR3022 potentially controls immune escape and extends the breadth of protection. At the same time, synergy between CR3014 and CR3022 may allow for a lower total antibody dose to be administered for passive immune prophylaxis of SARS-CoV infection. Late in 2002, severe acute respiratory syndrome (SARS) emerged in the Guangdong province of China. In February 2003, an infected doctor from the province carried this new viral threat to human health to Hong Kong. Here, people staying in the same hotel caught the disease and took it to other countries. SARS was on the move, hitching lifts with international travellers. Because the virus responsible for SARS—SARS-CoV—spread by close person-to-person contact and killed 10% of the people it infected, health experts feared a world-wide epidemic. This was avoided by the World Health Organization issuing a global alert and warning against unnecessary travel to affected areas and by public-health officials isolating patients and their close contacts. By July 2003, the first SARS epidemic was over. 8,098 people had been infected; 774 people had died. Since then, sporadic cases of SARS have been contained locally. The first epidemic of SARS was caused by an animal virus that became adapted to spread between people. There is no reason this process won't be repeated. If it is, stringent quarantine measures could again prevent a global epidemic, but at considerable economic cost. What is needed is a way to prevent SARS developing in healthy people who have been exposed to SARS-CoV and to treat sick people so that they are less infectious and can fight the virus. In this study, researchers have been investigating “passive immunization” as a way to limit SARS epidemics. In passive immunization, short-term protection against illness is achieved by injecting antibodies—proteins that recognize specific molecules (called antigens) on foreign organisms such as bacteria and viruses and prevent those organisms from causing disease. Antibodies for passive immunization can be isolated from blood taken from people who have had SARS, or they can be manufactured as so-called “human monoclonal antibodies” in a laboratory. One of these human monoclonal antibodies—CR3014—had been previously made and shown to prevent lung damage in ferrets infected with SARS-CoV and to stop the infected animals from infecting others. But for effective disease prevention in people, a single monoclonal antibody might not be enough. There are strains of SARS-CoV that CR3014 does not recognize and therefore cannot act against. Also, the virus can alter the antigen recognized by CR3014 when it is grown at a low antibody concentration, producing so-called escape variants; if this happens CR3014 can no longer prevent these escape variants from killing human cells. The researchers tested how well a combination of two monoclonal antibodies controlled SARS-CoV killing of human cells. First, they showed that CR3014 escape variants all had the same small change in a part of the virus surface that interacts with human cells. CR3014 blocked this interaction in the parent SARS-CoV strain but not in the escape variants. They then made a new monoclonal antibody—CR3022—that prevented both the parent SARS-CoV stain and the CR3014 escape viruses from killing human cells. The two antibodies bound to neighboring parts of the virus surface, and both of them could bind at the same time. CR3022 also bound to surfaces of SARS-CoV strains to which CR3014 does not bind. And when they tried, the researchers could not generate any viral escape variants to which CR3022 was unable to bind. Finally, the effect of the two antibodies together on inhibition of SARS-CoV killing of human cells was more than the sum of their individual effects. A combination of two (or more) human monoclonal antibodies that recognize different parts of the SARS-CoV surface that interacts with human cells might be a good way to immunize people passively against SARS-CoV. It might minimize the possibility of escape variants arising, broaden the range of virus strains against which protection is provided, and reduce the amount of antibody needed for effective protection. Before the approach is tried in people, it will have to be tested in animals—results from experiments done on human cells in dishes are not always replicated in whole animals or people. If the approach passes further tests, the hope is that passive immunization of people with SARS and their close contacts might reduce disease severity in infected people and reduce viral spread as effectively as dramatic quarantine measures Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0030237. • Medline Plus pages on SARS • US Centers for Disease Control and Prevention information on SARS • US National Institute of Allergy and Infectious Diseases factsheet about research on SARS • Wikipedia page on SARS and monoclonal antibodies (note: Wikipedia is a free online encyclopedia that anyone can edit) Two human monoclonal antibodies that bind to different parts of the viral glycoprotein spike show synergistic effects in virus neutralization and suppress the emergence of resistant virus in vitro.
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影响因子：
11.4
作者：
Li, WH;Zhang, CS;Sui, JH;Kuhn, JH;Moore, MJ;Luo, SW;Wong, SK;Huang, IC;Xu, KM;Vasilieva, N;Murakami, A;He, YQ;Marasco, WA;Guan, Y;Choe, HY;Farzan, M
通讯作者：
Farzan, M
影响因子：
5.6
作者：
DEKRUIF, J;BOEL, E;LOGTENBERG, T
通讯作者：
LOGTENBERG, T
影响因子：
5.4
作者：
CORAPI, WV;OLSEN, CW;SCOTT, FW
通讯作者：
SCOTT, FW
影响因子：
5.4
作者：
Cheung, CY;Poon, LLM;Peiris, JSM
通讯作者：
Peiris, JSM
影响因子：
8
作者：
Abramson, JS;Baker, CJ;Stark, AR
通讯作者：
Stark, AR