Human Monoclonal Antibodies that Bind Botulinum Toxins

描述（由申请人提供）：肉毒杆菌神经毒素（BoNT）是已知最有效的生物毒素，是麻痹性疾病、肉毒中毒的原因，也是潜在的生物恐怖主义武器。被动免疫与抗体疗法被认为是BoNT暴露的理想对策，其中最安全的是由人单克隆抗体组成。产生有效的BoNT抗体治疗策略的一个重要障碍是BoNT存在于至少7种血清型中，并且迄今为止克隆的大多数抗体不能结合多种血清型。此外，有效的中和需要使用三联体抗体组合，因此3种毒素血清型的中和至少需要9种不同的抗体。该项目通过探索能够结合和中和三种不同血清型BoNT （a、B和e）的人类单克隆抗体疗法的创建平台来解决这一问题。该计划的基础是人类抗体克隆的杂杂瘤方法，该方法已经产生了许多交叉反应性抗体。这与一种新的方法相结合，使用融合肽来增加BoNT抗体的体内效力，这可能会增加BoNT从血液中的清除率。该研究的一个重要方面是使用人单克隆抗体开发的超高灵敏度ELISA，这将允许在真实的体内暴露情况下进行低剂量BoNT与抗体融合肽复合物结合的药代动力学研究。

DESCRIPTION (provided by applicant): Botulinum neurotoxin (BoNT) is the most potent biological toxin known, the cause of the paralytic disease, botulism, and a potential bioterrorist weapon. Passive immunization with antibody therapeutics is considered to be the ideal countermeasure for a BoNT exposure, and the safest of these would be composed of human monoclonal antibodies. An important obstacle to the production of an effective antibody therapeutic strategy for BoNT is that BoNT exists in at least 7 serotypes, and most of the antibodies cloned thus far are not able to bind more than one serotype. In addition, effective neutralization requires that triplet combinations of antibodies be employed, so that neutralization of 3 toxin serotypes would require at least 9 distinct antibodies. This project addresses this problem by exploring a platform for the creation of human monoclonal antibody therapeutics capable of binding and neutralizing three distinct serotypes of BoNT, A, B, and E. The foundation of the plan is a hybridoma method of human antibody cloning that has generated a number of cross-reactive antibodies. This is combined with a novel means of increasing the in vivo potency of BoNT antibodies using a fusion peptide that may increase the rate of clearance of BoNT from the bloodstream. An important aspect of the study is an ultra-high sensitivity ELISA, developed using human monoclonal antibodies, which will allow pharmacokinetic study of low doses of BoNT bound to antibody:fusion peptide complexes in real-world in vivo exposure scenarios. PUBLIC HEALTH RELEVANCE: Botulinum neurotoxin (BoNT) has been listed as a Category A Select Bioterror agent by the Centers for Disease Control. Generation and study of multi-serotype-specific human antibodies, in combination with a novel technology for increasing BoNT clearance from the bloodstream, will help in the creation of a comprehensive therapeutic strategy for botulism or a BoNT bioterror attack. It will also provide a broad understanding of how similar approaches could be used to treat a variety of infectious diseases and toxin exposures.