Human Monoclonal Antibodies that Bind Botulinum Toxins

描述（由申请人提供）：肉毒杆菌神经毒素（BoNT）是一种非常有效的神经肌肉阻滞剂，已被美国政府指定为a类生物恐怖制剂，因为它具有极高的致命性和可从环境来源获得。目前针对BoNT暴露的对策是不足的，迫切需要能够抵消BoNT暴露影响的治疗性抗体。我们的工作假设是，结合BoNT的人类抗体组合将有效地保护个体免受BoNT暴露的并发症。我们最近开发了一种用于克隆人类抗体的新型杂交瘤方案，并使用它克隆了结合BoNT血清型a和b的抗体。其中血清型a抗体在体内中和。我们计划用我们的方法克隆结合和中和A和b型肉毒杆菌毒素的天然人抗体。为此，我们将从接种肉毒杆菌类毒素疫苗的个体中获得外周血淋巴细胞。我们将在体外和体内评估克隆抗体的中和活性，单独和联合。我们将描述抗体的结合和初级序列，以确定与中和毒素能力相关的特征，并在毒素中和中协同合作。这些实验的主要结果将是创造出能够有效抵抗BoNT/A和BoNT/B暴露的克隆人类抗体组合。

DESCRIPTION (provided by applicant): Botulinum neurotoxin (BoNT) is an extremely potent neuromuscular blocker that has been designated a category A select bioterror agent by the United States Government because of its extreme lethality and its availability from environmental sources. Current countermeasures for BoNT exposure are insufficient, and there is an urgent need for therapeutic antibodies able to counteract the effects of BoNT exposure. Our working hypothesis is that a combination of human antibodies that bind BoNT will potently protect individuals from the complications of BoNT exposure. We have recently developed a novel hybridoma protocol for the cloning of human antibodies and have used it to clone antibodies that bind BoNT serotypes A and B. One of the serotype A antibodies is neutralizing in vivo. We plan to use our method to clone native human antibodies that bind and neutralize botulinum toxin serotypes A and B. For this purpose we will obtain peripheral blood lymphocytes from individuals vaccinated with the botulinum toxoid vaccine. We will assess in vitro and in vivo neutralizing activities of the cloned antibodies, singly and in combination. We will characterize the binding and primary sequences of the antibodies to determine the features that correlate with the ability to neutralize toxin and to cooperate synergistically in toxin neutralization. The primary result of these experiments will be the creation of combinations of cloned human antibodies that can effectively counteract BoNT/A and BoNT/B exposure.