Role(s) of VEGF in Resolution of Inflammation

项目摘要 炎症是正常伤口修复的关键过程。一旦受伤，细胞因子被激活， 并将包括巨噬细胞在内的白细胞化学吸引到伤口部位。宏观经济是关键 用于肉芽组织的正确形成，因为它们可以清理伤口中的死细胞 并产生过多的细胞因子，启动愈合组织的形成。虽然许多 参与炎症早期的详细机制是已知的，那些参与炎症消退的机制是已知的。 对炎症知之甚少。了解炎症是如何结束的， 理解它的开始，因为炎症的延长导致愈合受损， 慢性炎症VEGF是伤口愈合的关键因素， 在血管生成中的作用。然而，最近VEGF作为免疫调节剂出现， 和炎症。我们已经发现VEGF有助于巨噬细胞的分解- 在伤口愈合过程中诱导炎症，并刺激巨噬细胞凋亡， 文化我们还发现，VEGF刺激TNFSF 14/LIGHT的表达。 人类巨噬细胞。LIGHT是已知的细胞因子TNF超家族的成员， 调节T细胞的共刺激以及粘膜肿瘤中的细胞凋亡。我们的发现表明 一种新的参与炎症反应消退的精氨酸调节途径。在 在这里提出的工作，我们解决这些新发现的功能的后果， VEGF在伤口愈合过程中炎症消退中的作用。我们假设一部小说 VEGF在愈合过程中的功能是调节受损组织中巨噬细胞的存活。 组织和光是这个过程的关键调解人。具体而言，我们将：（1）确定 VEGF是否在体内诱导巨噬细胞凋亡并刺激LIGHT表达 （2）确定VEGF诱导的巨噬细胞 细胞死亡与光我们将使用培养的人类巨噬细胞，正常和 基因修饰的小鼠，与VEGF和LIGHT依赖性的激动剂/拮抗剂偶联 途径。组织化学和免疫学技术、ELISA、多重RT-PCR和siRNA 技术将被使用。这项工作是新颖的，因为它揭示了以前未知的 VEGF的功能，它是重要的，因为它可以促进新疗法的发展 用于愈合不良的伤口以及以过度炎症为特征的其他病症 以及VEGF上调的肿瘤。因为炎症的消退很差， 或根本没有在大多数不正常的愈合情况下，这条线的调查是重要的健康 因为它确定了一种改善受损愈合的新策略，这是一个关键的医学领域。

PROJECT SUMMARY Inflammation is a key process in normal wound repair. Upon wounding, cytokines are activated and chemoattract leukocytes, including macrophages, to the wound site. Macrophages are key for the proper formation of granulation tissue because they clean up dead cells in the wound and produce a plethora of cytokines that initiate formation of the healing tissue. While many detailed mechanisms involved early in inflammation are known, those involved in resolution of inflammation are poorly understood. Understanding how inflammation ends is as important as understanding its beginning because prolongation of inflammation leads to impaired healing and chronic inflammatory conditions. VEGF is a key factor in wound healing and is primarily known for its role in angiogenesis. However, recently VEGF is emerging as a regulator of immunity and inflammation. We have discovered that VEGF contributes to resolution of macrophage- induced inflammation during wound healing and that it stimulates macrophage apoptosis in culture. We have also shown that VEGF stimulates the expression of TNFSF14/LIGHT in human macrophages. LIGHT is a member of the TNF superfamily of cytokines known to regulate co-stimulation of T cells as well as apoptosis in mucosal tumors. Our findings point to a novel cytokine-modulated pathway involved in resolution of the inflammatory response. In the work proposed here we address the consequences of these newly discovered functions of VEGF in resolution of inflammation during wound healing. We hypothesize that a novel function of VEGF in the healing process is modulation of macrophage survival in the damaged tissue and that LIGHT is a critical mediator of this process. Specifically, we will: (1) Determine whether VEGF induces macrophage apoptosis in vivo and stimulates LIGHT expression during healing and (2) Determine the relationship between VEGF-induced macrophage cell death and LIGHT. We will use a combination of cultured human macrophages, normal and genetically-modified mice, coupled with agonists/antagonists of VEGF- and LIGHT-dependant pathways. Histochemical and immunological techniques, ELISA, multiplex RT-PCR and siRNA technology will be used. The work proposed is novel because it reveals previously unknown functions of VEGF and it is important because it may facilitate the development of new therapies for poorly-healing wounds as well as other conditions characterized by excessive inflammation and for tumors in which VEGF is upregulated. Because resolution of inflammation occurs poorly or not at all in most abnormal healing situations, this line of investigation is significant for health because it identifies a novel strategy for improving impaired healing, a critical medical area.