Improving Protein Delivery and Circulation via FcRn Ligands

描述（由申请人提供）：许多挑战阻碍了蛋白质作为药物的更广泛使用，包括：它们从循环中快速消除以及需要通过注射给药蛋白质。克服这些限制的策略可以降低给药频率，提高患者的便利性和依从性。工程化蛋白质与MHC I类新生儿Fc受体（FcRn）相互作用代表了一种有前途的策略，以改善循环时间，并使蛋白质给药的替代途径。FcRn在多个器官和组织中表达，在保护IgG方面发挥独特作用 从catalysts和/或运输IgG穿过上皮屏障。以中等亲和力结合FcRn的肽序列已经通过噬菌体展示鉴定，并且可以适合于掺入蛋白质中以改善其药代动力学性质并使肺蛋白质递送成为可能。我们将研究影响FcRn结合肽修饰蛋白的循环时间和上皮转胞吞作用的因素，作为改善蛋白循环和实现肺部蛋白递送的一般策略。将积极追求三个具体目标。目标1. (A)合成FcRn的肽配体并确认它们结合并被FcRn转运;（B）在E.大肠杆菌中鉴定的序列，并表征其与FcRn的相互作用。目标2.在人FcRn转基因小鼠模型中确定FcRn结合、体内循环时间、肺吸收和肺滞留之间的关系。目标3。评价FcRn结合肽修饰的人生长激素（hGH）在生长激素缺乏症小鼠模型中的治疗潜力。我们的研究将产生一个更好的理解的因素，控制内化和转胞吞的货物连接到一个FcRn配体。这项研究的成功可以开发出具有方便给药途径的新的基于蛋白质的疗法，从而大大改善儿童和老年人等有问题患者群体的治疗。 公共卫生相关性：我们的目标是设计蛋白质与FcRn相互作用，并利用它们来确定影响FcRn介导的蛋白质循环和肺部吸收的因素。该计划的成功完成将导致一种新的方法来改善蛋白质递送和药代动力学，这可以转化为用于治疗人类疾病的改进的蛋白质疗法。

DESCRIPTION (provided by applicant): A number of challenges impede the more widespread use of proteins as drugs including: their rapid elimination from circulation and the need to dose proteins via injection. Strategies that overcome these limitations could decrease dosing frequency and improve patient convenience and compliance. Engineering proteins to interact with the MHC Class I-like neonatal Fc receptor (FcRn) represents a promising strategy to improve circulation time and enable alternative routes of protein administration. FcRn is expressed in several organs and tissues in which it serves a distinct role in the protection of IgG from catabolism and/or transport of IgG across epithelial barriers. Peptide sequences that bind to FcRn with moderate affinity have been identified by phage display and may be amenable for incorporation into proteins in order to improve their pharmacokinetic properties and enable pulmonary protein delivery. We will investigate factors that affect the circulation time and epithelial transcytosis of FcRn binding peptide-modified proteins as a general strategy to improve protein circulation and enable pulmonary protein delivery. Three specific aims will be aggressively pursued. Aim 1. (A) Synthesize peptides ligands for FcRn and confirm they bind and are transported by FcRn; (B) Generate recombinant FcRn binding fusion proteins in E. coli based upon sequences identified in Aim 1A and characterize their interaction with FcRn. Aim 2. Determine the relationship between FcRn binding, in vivo circulation time, pulmonary absorption, and pulmonary retention in a human FcRn transgenic mouse model. Aim 3. Evaluate the therapeutic potential of FcRn binding peptide-modified human growth hormone (hGH) in a murine model of growth hormone deficiency. Our studies will generate a better understanding of the factors that control internalization and transcytosis of cargos attached to an FcRn ligand. Success in this research could enable the development of new protein-based therapies with convenient routes of administration that could greatly improve treatment in problematic patient populations such as children and the elderly. PUBLIC HEALTH RELEVANCE: Improved PK and Delivery of Protein Modified with FcRn Binding Ligands Project Relevance Our goal is to engineer proteins to interact with FcRn and use them to define factors that affect FcRn mediated protein circulation and pulmonary absorption. Successful completion of the plan would result in a novel method to improve protein delivery and pharmacokinetics that could be translated into improved protein therapeutics for treating human disease.