Isolation of Peptide Radioprotectors

描述（由申请人提供）：全身暴露于电离辐射（IR）会导致辐射敏感组织的细胞损伤。因此，迫切需要开发用于癌症放射治疗和生物防御的高效放射防护剂。我们从细菌多肽中发现了一类新的辐射防护化合物，它们可以作为toll样受体（TLRs）的激动剂。我们的先导化合物CBLB502与TLR5结合并激活NF-kB促生存通路，从而保护IR损伤。该研究的第一阶段旨在通过筛选生物活性分泌蛋白（BASP）文库来改进CBLB502，并从诱导NF-kB通路的肽中鉴定新的辐射防护化合物。我们还将通过诱变获得高亲和力的CBLB502 BASP变体。不通过NF-kB起作用的潜在辐射防护肽将通过直接功能选择分离用于辐射防护。此外，拟议研究的I期完成将导致一种新的BASP筛选技术的开发和商业化，该技术基于完全控制氨基酸残基的短肽BASP文库的硅设计和构建，可兼容疾病相关细胞模型的功能筛选。这种方法是由于最近高通量（HT）芯片寡核苷酸合成和HT测序技术的创新而成为可能的。这种简单且成本效益高的方法代表了对当前药物发现策略的改进，并将加速新型肽疗法的发展。在第一阶段的资助下，我们建议在体外和体内开发和验证这种新资源。鉴于我们与罗斯威尔公园癌症中心基于细胞的药物筛选设施的独特接口，我们希望开发一个潜在的药物肽模拟管道，将知识快速转化为有效的药物鉴定策略。本研究的第二阶段提出了对分离肽作为潜在药物的深入表征。在完成拟议的研究后，我们预计将产生一类新的辐射防护药物。我们相信BASP筛选平台的开发将为新的生物相关肽药物的鉴定和验证提供一个有价值的工具集。这将有助于确定治疗干预的新靶点，并建立药物发现的范例。最重要的是，该项目将加快从实验室到临床的过渡，并为学术和工业研究人员提供一个强大的，具有成本效益的替代当前肽筛选策略。

DESCRIPTION (provided by applicant): Systemic exposure to ionizing radiation (IR) results in cell damage in radiosensitive tissues. It is therefore highly desirable to develop efficient radioprotective agents for use in cancer radiotherapy, and biodefense. We have discovered a new class of radioprotective compounds derived from bacterial polypeptides that act as agonists of Toll-like receptors (TLRs). Our lead compound, CBLB502, binds to TLR5 and activates the NF-kB pro-survival pathway, which protects from IR damage. Phase I of this proposed research aims to improve CBLB502 and to identify novel radioprotective compounds from peptides that induce the NF-kB pathway by screening the libraries of BioActive Secreted Proteins (BASP). We will also derive high affinity CBLB502 BASP variants by mutagenesis. Potential radioprotective peptides that do not act through NF-kB will be isolated by direct functional selection for radiation protection. In addition, completion of Phase I of the proposed research will result in the development and commercialization of a new BASP screening technology, based on the in silico design and construction of short peptide BASP libraries with full control of amino acid residues, which is compatible with functional screening in disease-relevant cell models. This method was made possible by recent innovations in high-throughput (HT) chip-based oligonucleotide synthesis and HT sequencing technology. This simple and cost-effective approach represents an improvement on current drug discovery strategies and will accelerate the development of novel peptide therapeutics. Under Phase I funding, we propose to develop and validate this novel resource in vitro and in vivo. Given our unique interface with the cell-based drug screening facilities at the Roswell Park Cancer Center, we expect to develop a pipeline of potential drug peptide mimics with fast conversion of knowledge into efficient strategies of drug identification. Phase II of this research proposes an in-depth characterization of the isolated peptides as potential drugs. At the completion of the proposed studies, we anticipate to generate a novel class of radioprotective drugs. We believe the development of BASP screening platform will provide a valuable tool set for the identification and validation of novel biologically relevant peptide drugs. It will help to identify novel targets for therapeutic intervention and establish paradigms for drug discovery. Most importantly, this project will expedite the transition from bench to clinic and provide both academic and industrial researchers with a robust, cost-effective alternative to current peptide screening strategies. PUBLIC HEALTH RELEVANCE: The goal of this project is to identify novel radioprotective agents for biodefense and cancer treatment by peptide screening. The libraries of bioactive secreted peptides will be functionally screened for suppression of radiation-induced cell death and validated in vivo.