Click Chemistry for Immobilized Bone Morphogenetic Protein

描述（申请人提供）：生长因子是一种有效的信号分子，启动细胞分化、增殖和生存的基本程序。直到最近，像生长因子这样的大分子才被用于提高医疗植入治疗的疗效和特异性。特别是，需要原生组织与植入材料相互作用的手术将受益于生长因子的加入。技术与生物学之间的成功结合通常预示着随后的治疗结果。affinenergy公司开发了双功能肽连接物，称为界面生物材料（IFBMs），有助于促进合成和生物之间的关键界面的生物学。将一种设计用于结合生长因子的肽连接到另一种设计用于结合医疗设备的肽上，提供了一种简单且针对特定目标的治疗策略。此外，我们的模块化方法允许肽半段的互换性，以产生潜在双功能ifbm的组合阵列。目前，我们用化学方法将肽合成为一个连续的序列。这种方法面临着巨大的挑战，因为当链长接近30个残基时，固相肽合成的偶联效率会急剧下降。我们提出了一项I期研究，探索使用[3 + 2]环加成或点击化学制备ifbm。该方法利用了我们的模块化方法，通过短肽（<25米）的偶联可以获得更高的总产率。此外，在未受保护的氨基酸侧链存在下的选择性偶联使完成的IFBM文库具有高通量筛选能力。我们已经生成了两种IFBMs，它们结合可吸收胶原海绵和骨形态发生蛋白（BMP）；一个使用点击化学，一个使用传统的固相合成。在我们的I期研究中，我们发现两种合成技术制备的ifbm具有几乎相同的生物稳定性和体外活性。这些目标的成功完成鼓励我们将IFBM技术扩展到其他生长因子和骨移植材料。我们在第二阶段的目标是优化IFBM制造的点击化学，检查原型IFBM的生物相容性，储存和灭菌，并测试它们在体内的功效。affinenergy的IFBM技术旨在通过三种潜在的方式改善生长因子治疗：1)促进BMP从现有载体的持续释放；2)减少提供所需治疗效果所需的重组生长因子的超生理量；2)从细胞外环境中捕获和浓缩内源性分子，有可能减少或消除对重组蛋白的需求。项目的叙述

DESCRIPTION (provided by applicant): Growth factors are potent signaling molecules, initiating essential cellular programs for differentiation, proliferation and survival. Only recently have large molecules like growth factors, been employed to enhance the efficacy and specificity of medical implant therapies. In particular, procedures that require native tissues to interact with an implanted material stand to benefit from inclusion of growth factors. A successful merger at the interface between technology and biology is generally predictive of subsequent therapeutic outcome. Affinergy Inc., has developed bifunctional peptide linkers, called interfacial biomaterials (IFBMs) that help promote biology at the critical interface between a synthetic and a biologic. Attaching one peptide designed to bind a growth factor, to another peptide designed to bind a medical device, offers a simple and target-specific therapeutic strategy. In addition, our modular approach allows interchangeability of peptide halves , to produce a combinatorial array of potential bifunctional IFBMs. Currently we chemically synthesize our peptides as one continuous sequence. This approach presents significant challenges, as coupling efficiency of solid-phase peptide synthesis decreases dramatically as chain length approaches 30 residues. We proposed a Phase I study, exploring the use of [3 + 2] cycloaddition or click chemistry to prepare IFBMs. This method takes advantage of our modular approach and allows for higher total yields through the coupling of shorter peptides (<25 mers). Additionally, selective coupling in the presence of unprotected amino acid side chains enables high-throughput screening capabilities of completed IFBM libraries. We have generated two IFBMs which bind a resorbable collagen sponge and a bone morphogenetic protein (BMP); one using click chemistry and one using traditional solid-phase synthesis. In our Phase I studies, we found nearly identical biostability and in vitro activity of IFBMs made with both synthesis techniques. Successful completion of these aims has encouraged us to expand our IFBM technology to other growth factors and bone graft materials. Our goal in Phase II is to optimize click chemistry for IFBM manufacturing, examine the biocompatibility, storage, and sterilization of prototype IFBMs, and test their efficacy in vivo. Affinergy's IFBM technology is designed to improve growth factor therapy in three potential ways: 1) promoting the sustained release of BMP from existing carriers; 2) reducing the supraphysiological amounts of recombinant growth factor required to provide the desired therapeutic effect and 2) capturing and concentrating endogenous molecules from the extracellular milieu, potential decreasing or eliminating the requirement for recombinant protein.Project Narrative Bone grafts currently take one of three forms, which include autograft (typically harvested from the patient's iliac crest) allograft (cadaveric bone) and synthetics (helistat sponge, hydroxyapatite or tricalcium phosphate). Autografts harbor all the endogenous biological capacity for bone regeneration, but represent a painful additional surgical step. Allograft and synthetics require no such secondary procedure, but have limited or no osteoinductive capabilities. Our goal is to therefore merge the benefits of both grafts, by adding a growth factor binding peptide coating to collagen-based bone grafts. We envision this technology as a means of reducing the dosage of expensive growth factors, while removing the pain and potential complications associated with bone harvesting. This technology is likely most applicable to intervertebral and posterior lateral spinal fusion, procedures growing in frequency and known to benefit from osteoinductive growth factors. With over 45,000 spinal fusion surgeries performed each year, the demand for improved technique, care and cost is unlikely to be soon assuaged.