Human Monoclonal Antibodies that Bind Botulinum Toxins

描述(申请人提供)：肉毒杆菌神经毒素(BONT)是已知的最有效的生物毒素，是麻痹疾病、肉毒杆菌中毒的原因，也是潜在的生物恐怖武器。抗体疗法的被动免疫被认为是治疗BONT的理想对策，其中最安全的是由人类单抗组成的。生产有效的抗体治疗策略的一个重要障碍是BONT至少存在于7个血清型中，而且到目前为止克隆的大多数抗体都不能结合一个以上的血清型。此外，有效的中和需要使用抗体的三重组合，因此中和3种毒素血清型需要至少9种不同的抗体。该项目通过探索一个能够结合和中和三种不同血清型的BoNT、A、B和E的人类单抗疗法的平台来解决这个问题。该计划的基础是一种人类抗体克隆的杂交瘤方法，该杂交瘤方法已经产生了许多交叉反应抗体。这与一种新的方法相结合，该方法使用融合肽来增加体内BONT抗体的效力，这种融合肽可能会增加BONT从血液中的清除率。这项研究的一个重要方面是使用人类单抗开发的超高灵敏度ELISA法，它将允许对与抗体结合的低剂量BONT进行药代动力学研究：在真实世界活体暴露情况下的融合肽复合体。 公共卫生相关性：肉毒杆菌神经毒素(BONT)已被疾病控制中心列为A类精选生物恐怖因子。多血清型特异性人类抗体的产生和研究，与增加血液中BONT清除的新技术相结合，将有助于创建针对肉毒杆菌中毒或BONT生物恐怖攻击的综合治疗策略。它还将提供对如何使用类似方法来治疗各种传染病和毒素暴露的广泛理解。

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.