VEGFR Signaling Controls Lymphatic Junctions

VEGFR 信号传导控制淋巴连接

基本信息

批准号：
10642854
负责人：
Joshua Paul SCALLAN
金额：
$ 66.31万
依托单位：
UNIVERSITY OF SOUTH FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-01 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10642854
关键词：
Address Adherens Junction Affect Beds Binding Biological Process Birth Blood Vessels Breast Cancer Patient Cell Culture Techniques Cells Cellulitis Data Development Disease Ear Embryo Excision FLT4 gene Fibrosis Functional disorder Gene Mutation Genes Hereditary lymphedema Heterozygote Hindlimb Image Impairment Infectious Skin Diseases Inherited Intercellular Fluid Intercellular Junctions KDR gene Knock-out Knockout Mice Knowledge Laboratories Leg Life Ligands Limb structure Link Liquid substance Lymph Lymphangiogenesis Lymphatic Lymphatic Capillaries Lymphatic function Lymphedema Maintenance Malignant Neoplasms Messenger RNA Missense Mutation Modeling Molecular Mus Mutation Near-infrared optical imaging Outcome Pathogenesis Patients Persons Pharmacological Treatment Pharmacotherapy Physiological Predisposition Protein Isoforms Proteins Receptor Protein-Tyrosine Kinases Respiratory Diaphragm Role Sepsis Signal Pathway Signal Transduction Skin Swelling Syndrome Tail Testing Tissues Tracer VEGFC gene Vascular Endothelial Growth Factor C Vascular Endothelial Growth Factor Receptor-1 Vascular Endothelial Growth Factor Receptor-3 Vascular Endothelium Work absorption cadherin 5 clinically relevant comorbidity drug development effective therapy in vitro Model in vivo insight knock-down lymph flow lymph nodes lymphatic dysfunction lymphatic malformations lymphatic vasculature lymphatic vessel lymphoscintigraphy methicillin resistant Staphylococcus aureus mouse model negative affect new growth notch protein novel overexpression pharmacologic postnatal receptor shear stress virtual

项目摘要

Congenital lymphedema is caused by inherited gene mutations that impair the functioning of the lymphatic vasculature and lead to swelling of the limbs, disfigurement, cellulitis, and increased susceptibility to MRSA infections of the skin and sepsis. Congenital lymphedema is also a comorbidity of lymphatic malformations and other common syndromes (e.g. Noonan). The most common gene mutation that causes congenital lymphedema is a heterozygous inactivating mutation in the VEGFR3 gene that causes Milroy’s disease. While VEGFR3 has been widely studied as the main receptor that induces lymphangiogenesis, virtually nothing is known about how VEGFR3 regulates physiological functions of the lymphatic vasculature. Thus, the pathogenesis of Milroy’s disease remains unknown, prohibiting the development of drug therapies. Patients with congenital mutations in VEGFR3 have lower leg lymphedema and upon lymphoscintigraphy imaging it is revealed that their lymphatic vessels are unable to absorb any tracer from the interstitium. Here, we have developed a mouse model in which the VEGFR3 gene can be deleted specifically from the lymphatic vasculature to understand its physiological functions. Our preliminary data show that loss of VEGFR3 negatively affects the ability of lymphatic capillaries to remodel their continuous cell-cell junctions, reminiscent of zippers, into discontinuous wide-open junctions called buttons. Junctional remodeling in the lymphatic capillaries is a relatively new biological process that is poorly understood but relies on the adherens junction protein, VE-cadherin, in which our laboratory has expertise. Importantly, the button junctions are thought to enable fluid absorption from the interstitium. Our preliminary data identify VEGFR3 as a novel regulator of lymphatic capillary junction remodeling to form button junctions. We will combine this mouse model with cell culture and physiological approaches to investigate the role of VEGFR3 in the lymphatic vasculature in the following specific aims. In Aim 1, we will assess the ability of lymphatic capillaries to remodel their junctions in the absence of VEGFR3 at various timepoints after birth. We will also investigate whether VEGFR3 is required not only for button junction formation, but also for the lifelong maintenance of these special junctions. Lymph flow will be assessed in vivo to determine how the loss of button junctions affects physiological interstitial fluid absorption. In Aim 2, we will investigate the downstream cell signals that regulate button junction formation and identify the signaling pathways involved using a variety of approaches. The completion of these aims will identify a new signaling pathway by which VEGFR3 controls lymphatic junction remodeling to enable interstitial fluid absorption by the lymphatic capillaries. This work will significantly impact patients with congenital lymphedema by providing mechanistic insight into the pathogenesis of the disease, opening the door to developing pharmacological treatments.

先天性淋巴水肿是由遗传性基因突变损害淋巴管功能引起的血管系统并导致四肢肿胀、毁容、蜂窝织炎以及增加对 MRSA 的易感性皮肤感染和败血症也是淋巴管畸形和脓毒症的合并症。其他常见综合征（例如 Noonan）导致先天性遗传病的最常见基因突变。淋巴水肿是导致 Milroy 病的 VEGFR3 基因杂合失活突变。 VEGFR3 作为诱导淋巴管生成的主要受体已被广泛研究，但实际上没有什么是已知 VEGFR3 如何调节淋巴管系统的生理功能。 Milroy 病的发病机制仍不清楚，阻碍了患者药物治疗的开发。具有 VEGFR3 先天性突变的患者有小腿淋巴水肿，经淋巴闪烁扫描成像发现研究表明，它们的淋巴管无法吸收间质中的任何示踪剂。开发了一种小鼠模型，其中 VEGFR3 基因可以从淋巴管中特异性删除我们的初步数据显示 VEGFR3 的丢失。对毛细淋巴管重塑其连续细胞-细胞连接的能力产生负面影响，让人想起拉链，进入称为纽扣的不连续的开放连接处。毛细血管是一种相对较新的生物过程，人们对其了解甚少，但依赖于粘附连接蛋白质，VE-钙粘蛋白，我们的实验室在这方面拥有专业知识，重要的是，按钮连接被认为是。我们的初步数据表明 VEGFR3 是一种新型的调节剂。我们将把这个小鼠模型与细胞结合起来。培养和生理学方法研究 VEGFR3 在淋巴管系统中的作用在目标 1 中，我们将评估毛细淋巴管重塑其连接处的能力。出生后各个时间点 VEGFR3 的缺失我们还将调查是否需要 VEGFR3。不仅用于纽扣连接的形成，还用于这些特殊连接的终生维护。将在体内评估流量以确定按钮连接的丢失如何影响生理间质液在目标 2 中，我们将研究调节纽扣连接形成和吸收的下游细胞信号。使用各种方法确定所涉及的信号通路将完成这些目标。确定 VEGFR3 控制淋巴管重塑以实现间质性的新信号通路这项工作将对先天性患者产生重大影响。通过提供对疾病发病机制的机制洞察，打开了治疗淋巴水肿的大门开发药物治疗。