Multivalent Conjugates for Enhanced Bioactivity of Growth Factor Based Therapies

用于增强生长因子疗法的生物活性的多价缀合物

基本信息

批准号：
8544176
负责人：
KEVIN Edward HEALY
金额：
$ 16.66万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-15 至 2015-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8544176
关键词：
American Amputation Angiogenic Factor Animal Model Area Back Beds Biological Biopolymers Blood Vessels Cellular Infiltration Chemistry Chronic Clinical Complications of Diabetes Mellitus Control Groups Coronary Dental Dermal Diabetes Mellitus Diabetic Angiopathies Diabetic ulcer Diabetic wound Diagnosis Digestion Disease Drug Formulations Drug or chemical Tissue Distribution Endothelial Cells Environment Erinaceidae Etiology Exhibits Fibroblasts Gene Expression Genes Goals Growth Factor Harvest Healed Health Care Costs Hyaluronic Acid Immunohistochemistry Impaired wound healing In Vitro Infection Infiltration Injury Insulin-Like Growth Factor I Investigation Ischemia Leg Ulcer Limb structure Lower Extremity Measures Metabolic Clearance Rate Modeling Molecular Muscle Natural regeneration Necrosis Orthopedics Pathway interactions Peptide Hydrolases Platelet-Derived Growth Factor Polymers Proteins Recombinant Growth Factor Saline Signal Transduction Site Sonic Hedgehog Pathway Technology Testing Therapeutic Thick Time Tissues Transcription Coactivator Translations Vascular blood supply Vascularization Vertebral column Wound Healing angiogenesis base db/db mouse design diabetic diabetic wound healing disease phenotype healing immune function improved in vivo macromolecule neovascularization novel therapeutic intervention prevent smoothened signaling pathway tissue regeneration treatment strategy wound wound vascularization

项目摘要

DESCRIPTION (provided by applicant): In 2010, more than 875,000 Americans with diabetes were diagnosed with a lower extremity ulcer. Failed closure of these wounds results in more than 73,500 lower extremity amputations annually. One common feature to these wounds is inadequate vascularization of the wound bed, leading to ischemia, infection, and necrosis. In addition to diabetic ulcers, limited vascularization during regeneration of coronary, orthopaedic, dental and muscle tissues are frequent diabetic complications. Several growth factors, including Sonic hedgehog (Shh), can enhance wound healing by promoting neovascularization in the wound, but they are rapidly cleared from the wound environment and subject to proteolytic digestion. Thus, the translation of growth factors as clinical therapies has been limited by their short duration of site-specific bioactivity in vivo. We have developed multivalent growth factor conjugates that are designed to enhance the bioactivity and tissue-level stability of growth factors to facilitate their clinical translation as biological therapeutics. Using this approach, w have conjugated Shh to linear chains of hyaluronic acid (HyA), and by varying the ratio of Shh:HyA, we can modulate its ability to activate the Shh pathway. Conjugating Shh to a large macromolecule may also prevent its deactivation by proteolytic enzymes and enhance its molecular stability in the target tissues. Our overall hypothesis is that multivalent conjugates of Shh (mvShh) will enhance and sustain Shh-induced gene expression that promotes neovascularization during diabetic wound healing. In Specific Aim 1, we will identify the mvShh formulations that yield maximal pathway activation in vitro using dermal fibroblasts harvested from db/db mice, a diabetic model animal that exhibits impaired wound healing and diminished angiogenic gene expression. In Specific Aim 2 we will correlate the bioactivity of mvShh conjugates to their ability to accelerate healing of full-thickness excisional wounds in db/db mice. Finally, in Specific Aim 3 we will use the same db/db wound healing model to investigate how multivalent presentation of Shh can enhance Shh-induced expression of angiogenic genes and blood vessel formation in vivo. By testing our hypothesis, we will evaluate mvShh conjugates as a treatment for diabetic ulcers. The general mechanism of multivalent conjugation of Shh in angiogenic signaling may also be extended to a variety of other microvascular disorders. Likewise, this study will build a rationale for multivalent conjugation as an enabling strategy for protein-based therapies that require local delivery and sustained bioactivity.

描述（由申请人提供）：2010年，有87.5万名糖尿病的美国人被诊断出患有下肢溃疡。这些伤口的闭合失败导致每年有73,500多个下肢截肢。这些伤口的一个共同特征是伤口床的血管化不足，导致缺血，感染和坏死。除糖尿病性溃疡外，冠状动脉，骨科，牙科和肌肉组织再生期间的血管化有限是常见的糖尿病并发症。包括声音刺猬（SHH）在内的几种生长因素可以通过促进伤口的新血管形成来增强伤口愈合，但它们可以从伤口环境中迅速清除并受到蛋白水解消化。因此，作为临床疗法的生长因子的翻译受到体内部位特异性生物活性持续时间的限制。我们已经开发了多价生长因子共轭物，旨在增强生长因子的生物活性和组织水平的稳定性，以促进其作为生物疗法的临床翻译。使用这种方法，W具有共轭SHH与透明质酸（HYA）的线性链，并通过改变SHH：HYA的比率，我们可以调节其激活SHH途径的能力。将SHH与大分子分子共轭也可以防止其通过蛋白水解酶失活并增强其在靶组织中的分子稳定性。我们的总体假设是 SHH（MVSHH）将增强和维持SHH诱导的基因表达，从而在糖尿病伤口愈合过程中促进新血管形成。在特定的目标1中，我们将使用从DB/DB小鼠中收获的真皮成纤维细胞在体外产生最大途径的MVSHH制剂，DB/DB小鼠是一种糖尿病模型动物，该模型表现出受损伤口愈合并减少血管生成基因的表达。在特定目标2中，我们将将MVSHH偶联物的生物活性与它们加速DB/DB小鼠的全厚度省区伤口的愈合能力相关联。最后，在特定目标3中，我们将使用相同的DB/DB伤口愈合模型来研究SHH的多价表示如何增强体内血管生成基因和血管形成的SHH诱导的表达。通过检验我们的假设，我们将评估MVSHH结合物作为糖尿病性溃疡的治疗方法。 SHH在血管生成信号传导中的多价结合的一般机制也可以扩展到各种其他微血管疾病。同样，这项研究将建立一个基于多价共轭的基本原理，作为基于蛋白质的疗法的促进策略，需要局部递送和持续的生物活性。