New Approaches To Passive Immunoprophylaxis

被动免疫预防的新方法

• 批准号: 7964628
• 负责人: Robert H. Purcell
• 金额: $ 106.45万
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7964628
• 关键词: Adverse effects; Animal Model; Animals; Anthrax disease; Antibodies; Antibody Therapy; Bacteria; Belgium; Binding; Biological Assay; Bioterrorism; Bone Marrow; Botulinum Toxins; Cell Culture Techniques; Centers for Disease Control and Prevention (U.S.); Characteristics; Chronic Hepatitis C; Clinical; Collaborations; Complex; Cooperative Research and Development Agreement; Dengue; Dengue Hemorrhagic Fever; Dengue Shock Syndrome; Dengue Virus; Disease; Ebola virus; Epitopes; Frankfurt-Marburg Syndrome Virus; Genotype; Globulins; Glycoproteins; Goals; HCV Vaccine; Hepatitis; Hepatitis A; Hepatitis B Virus; Hepatitis C; Hepatitis C virus; Hepatitis Viruses; Human; Human poliovirus; Immune response; Immunization; Immunoglobulins; Immunotherapeutic agent; Immunotherapy; Infection prevention; Interferons; Lassa fever virus; Lead; Libraries; Measures; Mediating; Monoclonal Antibodies; Pan Genus; Patients; Polioviruses; Population; Preparation; Prevention; Prevention therapy; Production; Prophylactic treatment; Public Health; Rabies virus; Recombinants; Retroviridae; Serotyping; Serum; Smallpox; Smallpox Viruses; Testing; Tick-Borne Encephalitis Virus; Tick-Borne Encephalitis Viruses; Time; Vaccinated; Vaccination; Vaccines; Vaccinia; Vaccinia virus; Vesicular stomatitis Indiana virus; Viral; Virulent; Virus; Virus Diseases; West Nile virus; anthrax protective factor; anthrax toxin; base; biodefense; capsule; combinatorial; human monoclonal antibodies; immunoprophylaxis; in vitro Assay; in vivo; interest; neutralizing antibody; neutralizing monoclonal antibodies; novel strategies; passive immunoprophylaxis; pathogen; programs; response; scale up; tool; vaccine candidate; virus envelope

Antibodies. Passive immunoprophylaxis has been an important public health tool. For example, normal immunoglobulin has been important in the prevention of hepatitis A. However, monoclonal preparations could be more potent, tailored to specific neutralization epitopes and highly consistent in potency. We have prepared combinatorial libraries from the bone marrow of chimpanzees that had been experimentally infected in sequence with each of the five human hepatitis viruses. Chimpanzee globulins are virtually identical to human immunoglobulins, making them attractive choices for immunoprophylactic and immunotherapeutic agents. To date, we have isolated monoclonal immunoglobulins that react with HAV, HBV, HDV and HEV. In other studies, we have recovered human monoclonal antibodies that react with HCV. Many of the monoclonal antibodies described above are neutralizing and their production is being scaled up for tests of passive immunoprophylaxis in a variety of animals and, eventually, in humans. These and the following studies have been extended through 2009. Construction of combinatorial libraries from bone marrow has also been carried out for chimpanzees that have been experimentally infected with dengue viruses 1 through 4: these have yielded important neutralizing monoclonal antibodies to dengue virus types 1, 2 and 4. More importantly, we have reestablished an animal model for antibody-mediated enhancement of dengue virus infections, which can lead to the more severe forms of dengue virus infection: dengue hemorrhagic fever and dengue shock syndrome. Furthermore, we have identified a deletion in the antibody molecule that abrogates enhancement, possibly making antibody therapy practical for the first time. We have extended our antibody studies to other viruses and bacteria of interest that can be experimentally administered to chimpanzees. For example, in response to new concerns about bioterrorism, we have prepared neutralizing monoclonal antibodies to vaccinia virus for use as immunoprophylactic/ immunotherapeutic agents in those who require immunization with vaccinia but who are susceptible to the side-effects of such immunization. More importantly, in collaboration with the CDC, we have demonstrated that monoclonal antibodies that neutralize vaccinia can also neutralize variola (the smallpox virus). Thus, these neutralizing monoclonal antibodies should be useful not only for prophylaxis and therapy of the side effects of vaccination but also for the prevention and therapy of smallpox, should it ever be released into populations. Similarly, we have immunized chimpanzees with anthrax toxin in an attempt to make monoclonal antibodies that could immediately neutralize anthrax in vivo and have isolated highly potent monoclonal antibodies that can neutralize all three anthrax toxins (PA, LF and EF), as well as bind to the capsule of B.anthracis and opsonize the bacterium. These and monoclonal antibodies that neutralize vaccinia and smallpox are the subjects of a CRADA with MacroGenics. We are also preparing chimpanzee monoclonal antibodies to the three serotypes of poliovirus, to rabies virus, to West Nile virus and to the tick-borne encephalitis virus complex. We have also added the seven toxins of Clostridium botulinum. Some of these will have potential utility in efforts to counteract bioterrorism and all will have immunoprophylactic and immunotherapeutic potential in the battle against emerging and re-emerging pathogens. An impediment to understanding the immune response to hepatitis C virus (HCV) has been the inability to measure neutralizing antibodies because most HCV strains do not replicate in cell culture. We previously demonstrated neutralizing antibodies in an in vivo neutralization assay utilizing chimpanzees. This has been the only accepted neutralization assay until recently, when an in vitro assay based on the neutralization of recombinant retroviruses bearing the envelope glycoproteins of HCV was developed. We demonstrated that this assay generally correlated with the in vivo assay and that the neutralizing antibodies were more broadly reactive than previously thought. We have applied the pseudo-typed virus neutralization assay to sera from chimpanzees experimentally vaccinated with two candidate antibody-based HCV vaccines and have shown that one vaccine, which was effective in preventing infection, hepatitis and chronicity in most animals following challenge with virulent HCV stimulated high levels of broadly neutralizing antibody, whereas the other vaccine, which was completely ineffective in preventing infection, hepatitis or chronicity, completely failed to stimulate neutralizing antibodies as measured by the pseudo-typed virus assay. Broadly neutralizing monoclonal antibodies have been identified for HCV through a CRADA with Innogenetics, Ghent, Belgium. These monoclonal antibodies, directed against the E1 envelope glycoprotein of HCV, were recovered from a patient who had been successfully treated for chronic hepatitis C with interferon. The monoclonal antibodies were highly neutralizing and broadly reactive in the pseudo-typed virus assay. The results obtained with them (and with other polyclonal sera) suggest that hepatitis C viruses, which consist of six genotypes, may comprise two or three serotypes. It is hoped that these monoclonal neutralizing antibodies will find clinical utility in the prevention and therapy of HCV infections. Also in FY 2009, we have initiated a program whereby chimpanzees are being immunized with candidate vaccines against Ebola virus, Marburg virus and Lassa fever virus. Briefly, we are utilizing vesicular stomatitis virus (VSV) that has been modified by replacing the VSV envelope with glycoproteins of the BSL4 viruses. These chimeric viruses, developed by Heinz Feldmann, have been shown to be highly protective as vaccines in animal studies. Our goal is to recover potent neutralizing monoclonal antibodies that can be tested for immunoprophylaxis and immunotherapy. Previous attempts to generate such antibodies have yielded mixed results for reasons that are not completely clear but may be related to enhancing activity of certain antibodies. We plan to evaluate both the neutralizing and the enhancing activity of recovered antibodies and, if necessary, modify their FC portions to abolish enhancement but not neutralization, similar to what we have done with anti-dengue monoclonal antibodies.

抗体。被动免疫预防一直是重要的公共卫生工具。例如，正常的免疫球蛋白在预防肝炎A中很重要。但是，单克隆制剂可能更有效，针对特定的中和表位量身定制，并且在效力方面高度一致。我们已经从黑猩猩的骨髓中制备了组合文库，这些库是通过实验性地感染的五种人类肝炎病毒。黑猩猩球蛋白实际上与人类免疫球蛋白相同，使其成为免疫预防和免疫治疗剂的有吸引力的选择。迄今为止，我们已经与HAV，HBV，HDV和HEV有孤立的单克隆免疫球蛋白。在其他研究中，我们恢复了与HCV反应的人类单克隆抗体。上面描述的许多单克隆抗体都处于中和，并且它们的产生正在缩放，以测试各种动物，最终在人类中的被动免疫预防测试。这些研究和以下研究已经扩展到2009年。还针对已经在实验上感染了登革热病毒1到4的黑猩猩进行了骨髓组合文库的构建：这些型：这些抗体型1、2和4。替代了dytim dimand dymand dimand dytim dimand dytim dimand dytim dimand dytim dimple dime and dimem dimand dytim dimples dytim dimand dytim dimple dimand dytim dimand dimand dyter n dimem dimand dyter dy'感染，可能导致更严重的登革热病毒感染：登革热大量热和登革热综合征。此外，我们已经确定了抗体分子中的缺失，该抗体分子消除了增强，可能是第一次使抗体疗法实用。我们已经将我们的抗体研究扩展到了其他可以实验给黑猩猩的病毒和感兴趣的细菌。例如，为了回应对生物恐怖的新关注，我们已经准备了对疫苗病毒的单克隆抗体中和，以用作对疫苗但需要免疫免疫但对这种免疫效果敏感的人进行免疫接种的人的免疫预防/免疫治疗剂。更重要的是，与CDC合作，我们证明了中和离子疫苗的单克隆抗体也可以中和Variola（天花病毒）。因此，这些中和的单克隆抗体不仅适用于预防和治疗疫苗接种的副作用，而且对于预防和治疗天花的副作用也应释放到人群中。同样，我们使用炭疽毒素进行了免疫黑猩猩的免疫，试图制造单克隆抗体，可以立即中和体内炭疽病，并具有孤立的高效单克隆抗体，可以中和，以中和所有三种炭疽毒素（PA，LF和EF）（PA，LF和EF）（PA，LF和EF），并与Capsule and b.anthracis and b.anthracs and capsuil and capsuil and capsuil and of Capsul and of Capsul and of Capsul and of Capsul and of B.Sonson和exo of of b.son and of Capsul and of B.Son。这些中和疫苗和天花的单克隆抗体是具有宏观植物的Crada的受试者。我们还为脊髓灰质炎病毒的三种血清型，狂犬病病毒，西尼罗河病毒和tick传播脑炎病毒复合物准备了黑猩猩的单克隆抗体。我们还添加了肉毒梭菌的七种毒素。其中一些将在抵消生物恐怖主义方面具有潜在的效用，并且在反对新兴和重新出现病原体的战斗中，所有这些都将具有免疫性和免疫治疗潜力。 理解对丙型肝炎病毒（HCV）的免疫反应的障碍是无法测量中和抗体的障碍，因为大多数HCV菌株在细胞培养中不会复制。我们以前在使用黑猩猩的体内中和测定中证明了中和抗体。直到最近，这是唯一接受的中和分析，当时开发了基于携带HCV包膜糖蛋白的重组逆转录病毒的中和化学测定。我们证明了该测定法通常与体内测定法相关，并且中和抗体的反应性比以前认为的更广泛。 We have applied the pseudo-typed virus neutralization assay to sera from chimpanzees experimentally vaccinated with two candidate antibody-based HCV vaccines and have shown that one vaccine, which was effective in preventing infection, hepatitis and chronicity in most animals following challenge with virulent HCV stimulated high levels of broadly neutralizing antibody, whereas the other vaccine, which was completely ineffective in preventing通过伪型病毒测定法测量的感染，肝炎或慢性病完全未能刺激中和抗体。通过具有Innogentics，Ghent，Belgium的Crada确定了HCV的广泛中和单克隆抗体。这些针对HCV的E1包膜糖蛋白的单克隆抗体是从已成功治疗与干扰素慢性乙型肝炎治疗的患者中回收的。单克隆抗体在伪型病毒测定中高度中和，并具有广泛的反应性。 用它们获得的结果（以及其他多克隆血清）表明，甲型肝炎病毒由六种基因型组成，可能包括两种或三种血清型。希望这些单克隆中和抗体能够在预防和治疗HCV感染方面找到临床实用性。 同样在2009财年，我们启动了一项计划，该计划通过针对埃博拉病毒，马堡病毒和Lassa发烧病毒对候选疫苗进行免疫接种。 简而言之，我们正在利用囊泡口腔炎病毒（VSV），通过用BSL4病毒的糖蛋白代替VSV包膜来改变。 这些由亨氏·费尔德曼（Heinz Feldmann）开发的嵌合病毒已被证明是动物研究中的疫苗高度保护性。 我们的目标是恢复可用于免疫预防和免疫疗法的有效中和单克隆抗体。 以前的生成此类抗体的尝试已经产生了混合的结果，原因不完全清楚，但可能与增强某些抗体的活性有关。 我们计划评估回收抗体的中和和增强活性，并在必要时修改其FC部分以废除增强，而不是中和，类似于我们对抗爆炸单核抗体所做的类似。