IRF6 in the Inflammatory Phase of Cutaneous Wound Healing

描述(由申请人提供)：先天免疫系统在炎症的启动和适当的伤口愈合中至关重要。在调节免疫反应的分子中，有干扰素调节因子(IRF)家族的转录因子。尤其令人感兴趣的是IRF6，它是这个家族中的一个独特成员，也是伤口愈合的转录调节因子。事实上，范德伍德综合征(VWS)是一种由IRF6单倍体功能不全引起的常染色体显性遗传性口面部裂综合征，其患者在矫正手术后比非综合征形式的口面部裂患者更有可能出现伤口并发症。IRF6的缺失会导致小鼠的头面部、四肢和表皮异常，导致新生儿死亡。我们最近在肉芽组织中发现了强烈的irf6信号。 切除创面的组织，尤其是巨噬细胞和中性粒细胞。初步数据显示，与对照组相比，VWS患者的中性粒细胞体外趋化能力受损。此外，在一种独特的小鼠模型中，有条件地去除中性粒细胞和巨噬细胞中的IRF6，在一个简单的炎症模型中，细胞内流减少了三倍。最后，皮肤创面愈合在伤后7天严重受损。尽管IRF家族其他成员在先天免疫中的作用已经被很好地描述，但关于IRF6在先天免疫细胞中的功能以及它如何影响皮肤伤口愈合的炎症阶段，人们还不清楚。这一建议的中心假设是，在创伤愈合的背景下，IRF6是巨噬细胞和中性粒细胞在体外和体内正常发挥功能所必需的。在特定的目标#1中，我们将使用Luminex试验和迁移试验的实时成像来检验IRF6调节巨噬细胞和中性粒细胞的分泌和迁移的假设。在特定的目标#2中，我们将使用我们的IRF6条件基因敲除小鼠与溶酶酶驱动的Cre重组酶小鼠模型杂交，直接测试先天免疫细胞中Irf6的表达对于伤口愈合的适当炎症阶段是必需的这一假设。这项建议的创新之处在于，它将最近发现的IRF6在表皮形态发生和生物学中的作用扩展到天然免疫和皮肤伤口愈合--这一过程从临床角度来看非常重要，也是与健康相关的成本上升的主要原因。A随着这些研究的完成，我们将更好地了解IRF6对 皮肤伤口愈合过程中的炎症过程。由于持续性炎症是一种导致慢性伤口、慢性阻塞性肺疾病的现象，也与癌症有关，因此将获得关于这些常见健康问题的潜在病理生理机制的新信息。 公共卫生相关性：与公共健康的相关性这项提案将评估干扰素调节因子6在皮肤伤口愈合的炎症中的作用，皮肤伤口愈合是与健康相关的成本上升的主要原因。我们希望更好地了解身体在受伤后如何闭合洞口和形成接缝。这项工作可能适用于任何炎症性疾病，包括糖尿病、自身免疫性疾病、慢性伤口和癌症。

DESCRIPTION (provided by applicant): The innate immune system is of critical importance in the initiation of the inflammation and proper wound healing. Amongst molecules modulating the immune response are the transcription factors of the interferon regulatory factor (IRF) family. Of particular interest is IRF6, a unique member of this family and a transcriptional regulator of wound healing. Indeed, patients with Van der Woude syndrome (VWS), an autosomal dominant orofacial clefting syndrome caused by IRF6 haploinsufficiency, are more likely to have wound complications following corrective surgery than patients with a non-syndromic form of orofacial clefting. Loss of Irf6 results in craniofacial, limb and epidermal anomalies in the mouse, leading to neonatal mortality. We recently identified the presence of strong Irf6 signal in the granulation tissue of excisional wounds, particularly in macrophages and neutrophils. Preliminary data show that neutrophils from patients with VWS have impaired chemotaxis in vitro compared to controls. Furthermore, conditional removal of Irf6 in neutrophils and macrophages in a unique murine model results in a three fold reduction of cellular influx in a simple model of inflammation. Finally, cutaneous wound healing was severely impaired seven days post-wounding. Although the function of other IRF family members in innate immunity is well described, nothing is known about the function of IRF6 in innate immune cells and how it affects the inflammatory phase of cutaneous wound healing. The central hypothesis of this proposal is that Irf6 is required for proper macrophages and neutrophils function in vitro and in vivo in the context of wound healing. In specific aim #1, we will test the hypothesis that Irf6 regulates the secretion and migration of macrophages and neutrophils using luminex assay and live imaging of migration assays. In specific aim #2, we will directly test the hypothesis that expression of Irf6 in innate immune cells is necessary for the proper inflammatory phase of wound healing using our Irf6-conditional knockout mouse crossed with a lysosyme-driven Cre-recombinase mouse model. This proposal is innovative in that it extends the recently discovered role of Irf6 in epidermal morphogenesis and biology to innate immunity and cutaneous wound healing-a process that is highly significant from a clinical perspective, and a major cause of rising health-related costs. A the completion of these studies, we will have a better understanding of the contribution of Irf6 to the inflammatory process during cutaneous wound healing. Because continuous inflammation is a phenomenon leading to chronic wounds, chronic obstructive pulmonary disease, and is also implicated in cancer, new information will be obtained about a potential pathophysiological mechanism for these other common health concerns. PUBLIC HEALTH RELEVANCE: Relevance to Public Health This proposal will evaluate the role of Interferon Regulatory Factor 6 in inflammation in the context of cutaneous wound healing, a major cause of rising health-related costs. We expect to better understand how body closes holes and forms seams following injury. This work could have application to any inflammatory disease, including diabetes, autoimmune disorders, chronic wounds and cancer.