Isolation of Peptide Radioprotectors

描述(由申请人提供)：全身暴露在电离辐射(IR)中会导致辐射敏感组织的细胞损伤。因此，开发用于癌症放射治疗和生物防御的高效辐射防护剂是非常可取的。我们发现了一类新的辐射防护化合物，这些化合物来自于作为Toll样受体(TLRs)激动剂的细菌多肽。我们的先导化合物CBLB502与TLR5结合，并激活核因子-kB亲生存途径，从而保护免受IR损伤。这项拟议研究的第一阶段旨在改进CBLB502，并通过筛选生物活性分泌蛋白(BASP)文库，从诱导核因子-kB途径的多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突变体。不通过核因子-kB作用的潜在辐射防御肽将通过直接功能选择来分离用于辐射防护。此外，拟议研究的第一阶段的完成将导致一种新的BASP筛选技术的开发和商业化，该技术基于电子设计和构建完全控制氨基酸残基的短肽BASP文库，该文库与疾病相关细胞模型中的功能筛选相兼容。高通量芯片寡核苷酸合成和高通量测序技术的最新创新使这种方法成为可能。这种简单且经济有效的方法代表着对现有药物发现策略的改进，并将加速新肽疗法的发展。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一新资源。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，我们希望开发一条潜在药物多肽模拟的管道，将知识快速转化为有效的药物识别策略。这项研究的第二阶段提出了对分离的多肽作为潜在药物的深入表征。在拟议的研究完成后，我们预计将生产一类新型的辐射防护药物。我们相信，BASP筛选平台的开发将为新的生物相关多肽药物的鉴定和验证提供有价值的工具集。它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BASE到临床的过渡，并为学术和工业研究人员提供一种强大的、成本效益高的替代当前肽筛选策略的方法。 公共卫生相关性：该项目的目标是通过多肽筛选来确定用于生物防御和癌症治疗的新型辐射防护剂。生物活性分泌肽的文库将从功能上筛选，以抑制辐射诱导的细胞死亡，并在体内进行验证。

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.