Formulation and Encapsulation of Enzymic Countermeasures Against Organophosphorus

项目负责人/主要研究者（最后，第一，中间）：MAGLIERY，托马斯J。 项目总结/摘要 有机磷（OP）神经毒剂（例如，VX和沙林）和杀虫剂（例如，毒死蜱/Dursban）是 是已知毒性最强的化合物之一由于这些杀虫剂在世界各地的持续使用， 由于许多国家都有神经毒剂的库存，OP毒剂代表了一个重要的 恐怖袭击和工业事故造成的大规模伤亡威胁。OP的治疗方案 中毒会导致失能，不能治疗低剂量暴露的后遗症或影响; 在大规模伤亡的情况下很困难。解决这一问题的一个办法是开发一种酶对策 可以在OP剂发挥其全部作用之前快速降解OP剂。最近取得了一些进展 在催化生物清除剂的开发中，例如对氧化酶-1（PON 1）的工程突变体， 尤其是对付G特工通过美国陆军之间的合作， 化学防御医学研究所（USAMRICD）、俄亥俄州州立大学（OSU）和魏茨曼 研究所，PON 1的几种高活性变体已经在几内亚进行了工程设计，表征和测试 猪的初步药代动力学和保护效力。具有针对环沙林和环己基沙林的活性的变体 已经描述了针对G代理的频谱，最近的工作已经确定了几个预期的变体 对几种OP杀虫剂有效。我们建议在这里初步表征配方 这将直接导致在大规模伤亡情况下最有用的可注射酶。 该提案的总体目标是开发一种稳健的、封装的PON 1变体， 与肌内给药相容，以便在大规模伤亡情况下发挥最大效用。Cmax降低， 增加的T1/2和增强的贮存稳定性都预期是由本发明的纳米颗粒制剂引起的。 酵素来自俄勒冈州立大学的蛋白质生物化学家和来自 西南研究所（SwRI）已经合作实现这一目标。该提案将决定 在酶活性方面用于包封几种PON 1变体的最佳方法和聚合物， 稳定然后，纳米颗粒的溶解度和降解将通过用以下物质衍生化来调节： 不同尺寸的聚乙二醇（PEG）。最后，最好的衍生化，封装的变体将是 配制用于IM施用并在体外测试。USAMRICD的CounterACT U 54测试核心将是 用于确定最佳IM的药代动力学、保护功效和暴露后功效 公式化。这些实验将为U 54中心的更新项目提供基础， 格兰特，或一个独立的U 01直接在选定的PON 1变异体的最终制剂。 PHS 398/2590（Rev.06/09）

Program Director/Principal Investigator (Last, First, Middle): MAGLIERY, Thomas J. PROJECT SUMMARY/ABSTRACT Organophosphorus (OP) nerve agents (e.g., VX and sarin) and pesticides (e.g., chlorpyrifos/Dursban) are among the most toxic compounds known. Because of the continued use of these pesticides around the world, and because many nations are known to have stockpiles of nerve agents, OP agents represent a significant mass casualty threat from both terrorist attacks and industrial accidents. The treatment regimen for OP poisoning results in incapacitation and does not treat sequelae or effects of lower-dose exposures; it is also difficult in mass casualty scenarios. A solution to this problem is development of an enzymic countermeasure that can rapidly degrade the OP agents before they can exert their full effect. There has been recent progress in the development of catalytic bioscavengers, such as engineered mutants of paraoxoase-1 (PON1), particularly against G-agents. Through a CounterACT U54 grant that is a collaboration among the U.S. Army Medical Institute of Chemical Defense (USAMRICD), The Ohio State University (OSU), and The Weizmann Institute, several highly-active variants of PON1 have been engineered, characterized and tested in guinea pigs for preliminary pharmacokinetics and protective efficacy. Variants with activity against cyclosarin and against a spectrum of G agents have been described, and recent work has identified several variants expected to be effective against several OP pesticides. We propose here preliminary characterization of formulations that would directly lead to injectable enzymes most useful in mass casualty situations. The overall goal of this proposal is to develop a robust, encapsulated PON1 variant formulated to be compatible with intramuscular administration for maximum utility in mass casualty situations. Decreased Cmax, increased t1/2, and enhanced shelf stability are all anticipated to result from nanoparticle formulation of the enzyme. A team of protein biochemists from OSU and encapsulation and nanomaterials experts from Southwest Research Institute (SwRI) have partnered to achieve this goal. This proposal will determine the optimum methods and polymers for encapsulation of several PON1 variants in terms of enzyme activity and stability. The solubility and degradation of the nanoparticles will then be tuned by derivatization with polyethyleneglycols (PEGs) of different sizes. Finally, the best derivatized, encapsulated variants will be formulated for IM administration and tested in vitro. The CounterACT U54 Testing Core at USAMRICD will be used to determine pharmacokinetics, protective efficacy, and post-exposure efficacy for the best IM formulation. These experiments will provide the basis for either a project in the renewal of the U54 Center grant, or an independent U01 directed at final formulation of selected PON1 variants. PHS 398/2590 (Rev. 06/09) Page Continuation Format Page