Diverse mix of Human MoAbs to treat Anthrax exposure

描述(由申请人提供)：这项建议的长期目标(第一阶段和第二阶段)是开发一种基于人类单抗的制剂，用于治疗炭疽杆菌(炭疽)暴露或用于预防使用。这种制剂很可能由多个不同的单抗组成。这种制剂将填补可用于治疗这一生物武器威胁的试剂库中的一个重大空白。 第一阶段的具体目标是： 1)评价AVA疫苗免疫供者外周血白细胞在人淋巴细胞移植SCID小鼠(HU-PBL-SCID系统)中的人源抗体反应。免疫原包括a)重组保护性抗原(PA)，b)PA的活性片段，c)致死因子(LF)，以及(可选)d)由PA+LF形成的致死毒素。抗原特异性的人类血清抗体将通过‘ELISA检测，中和抗体水平将使用小鼠巨噬细胞系RAW进行测量。 2)评价致死毒素处理作为体内筛选产生中和抗体的小鼠的方法。 3)从选定的动物中产生一系列针对PA和可能针对LF的人类单抗。这些将被表征为中和活性，并使用Biacore，亲和力和表位分组。 第二阶段提案的主要目标将是配置至少一种人类单克隆体组合，可在体内评估其保护和/或拯救炭疽杆菌挑战的能力。第二阶段SBIR计划可能需要在第一阶段成功的基础上产生一组更大的抗体。

DESCRIPTION (provided by the applicant): The long-term goal of this proposal (phase I and II) is the development of a human monoclonal antibody-based preparation for use in treating B. anthracis (anthrax) exposure or for use prophylactically. This preparation would most likely be composed of multiple, different monoclonal antibodies. Such a preparation would fill a significant void in the arsenal of reagents available to treat this biowarfare threat. Phase I specific aims are: 1) Evaluate the human antibody response of peripheral blood leukocytes from AVA vaccinated donors in the human lymphocyte engrafted SCID mouse (hu-PBL-SCID system). Immunogens will include a) recombinant Protective Antigen (PA), b) the active fragment of PA, c) Lethal Factor (LF), and (optionally) d) the Lethal Toxin formed from PA+LF. Antigen specific serum human antibodies will be detected by 'ELISA, and neutralizing antibody levels will be measured using the murine macrophage cell line RAW. 2) Evaluate Lethal Toxin treatment as an in vivo approach to select mice making neutralizing antibodies. 3) Generate, from selected animals, an initial series of human monoclonal antibodies specific for PA, and possibly LF. These will be characterized for neutralizing activity, and using BIACORE, affinity and epitope grouping. The main goal of the phase II proposal will be the configuration of at least one combination of human monoclonals which could be evaluated in vivo for the ability to protect and/or rescue from B. anthracis challenge. The phase II SBIR program may require the generation of a larger panel of antibodies, based on the success of phase I.