VIP and Disease Resolution of Bacterial-Induced Ocular Infection

简介(申请人提供)：背景。铜绿假单胞菌(PA)引起的角膜炎是最常见和最具破坏性的细菌性疾病之一，最终导致失明。这种机会主义的革兰氏阴性细菌最为人所知的是在戴隐形眼镜的人中引起细菌性角膜炎。仅在美国，每年微生物角膜炎的发病率就有25,000-30,000例，治疗费用估计为1,500-3,000万美元。目标/假设。这种威胁视力的疾病在很大程度上是宿主引发的炎症反应的结果，这取决于免疫细胞的调节，这些细胞和微环境释放的促炎和抗炎因子之间的平衡，以及组织内稳态的有效恢复。在这方面，鉴于抗生素耐药性的增加，血管活性肠肽(VIP)，一种28个氨基酸 神经肽被认为是一种有效的内源性免疫调节剂，以抗炎的方式影响免疫反应。我们的目标是利用角膜感染性疾病的小鼠模型来描述VIP诱导的炎症和先天免疫的前化解机制。此外，启动VIP作为治疗角膜感染性疾病的临床前研究。明确的目标。这项建议的目的是：1)确定血管活性肠肽对炎症的特殊前分解介质(SPM)的表达/激活的影响；2)研究血管活性肠肽如何影响γδT细胞和IL-17的产生，以推动炎症的溶解；3)确立血管活性肠肽治疗细菌性角膜炎的疗效，以对抗多种PA菌株。研究设计。眼部感染会 诱导方法如下：每只动物的右眼被切开，并将含有1x106CFU PA的5mL等量局部涂抹在受伤的角膜表面。实验动物(VIP处理的B6小鼠)和对照组(PBS处理的B6小鼠和PBS处理的BALB/c小鼠)之间的疾病反应和解决机制将使用一些成熟的技术进行比较，以评估免疫细胞的激活状态、脂类介体(脂氧素、溶血素、保护素)的表达和激活以及其他炎症参数。此外，将进行研究，以建立VIP的临床前相关治疗模式(例如，药物输送模式、感染后开始治疗、对抗细胞毒性和侵袭性PA菌株的疗效)。冲击力。该项目从治疗角度研究免疫和神经内分泌系统之间的相互作用如何在解决眼部感染以及随后保护视觉神经系统和视力方面发挥重要作用。特别是，拟议的研究将为细菌性角膜炎的人类治疗奠定坚实的临床前相关性基础。

DESCRIPTION (provided by applicant): Background. Pseudomonas aeruginosa (PA)-induced keratitis is one of the most common and destructive of bacterial diseases, ultimately culminating in blindness. This opportunistic, Gram-negative organism is best known to cause bacterial keratitis in extended contact lens wearers. In the United States alone the incidence of microbial keratitis is 25,000-30,000 cases annually with cost of treatment estimated at $15-30 million. Objective/Hypothesis. This sight-threatening disease is in large part a consequence of the inflammatory response invoked by the host, which depends on the regulation of immune cells, balance between pro- and anti-inflammatory factors released by these cells and the microenvironment, and effective restoration of tissue homeostasis. In this regard and in light of increasing incidence of antibiotic resistance, vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide, has been implicated as a potent endogenous immunomodulator that affects the immune response in an anti-inflammatory manner. The goal is to delineate the VIP-induced pro-resolving mechanisms of inflammation and innate immunity using a murine model of corneal infectious disease. Furthermore, initiate pre-clinical studies for VIP as a therapeutic treatment for corneal infectious disease. Specific Aims. This proposal intends to: 1) ascertain the effects of VIP regarding expression/activation of specialized pro-resolving mediators (SPMs) of inflammation; 2) examine how VIP influences γδ T cells and the production of IL-17 in driving inflammatory resolution; and 3) establish the efficacy of VIP treatment as a clinically relevant therapy for bacterial keratitis against multiple strains of PA. Study Design. Ocular infection will be induced as follows: the right eye of each animal will be scarified, and a 5 mL aliquot containing 1 x 106 CFU PA will be topically applied to the wounded corneal surface. Disease response and mechanisms of resolution will be compared between experimental (VIP-treated B6 mice) and control (PBS-treated B6 mice and PBS-treated BALB/c mice) animals using a number of well-established techniques to assess the activation state of immune cells, expression and activation of lipid mediators (lipoxins, resolvins, protectins), and other parameters of inflammation. In addition, studies will be carried out to establish pre-clinically relevant treatment modalities for VIP (e.g., modes of drug delivery, initiation of treatment post-infection, efficacy against cytotoxic and invasive strains of PA). Impact. The project examines therapeutically how interactions between the immune and neuroendocrine systems play an essential role in the resolution of ocular infection and subsequent preservation of the visual nervous system and visual acuity. In particular, the proposed studies will establish a solid basis of pre-clinical relevance to human treatment of bacterial keratitis.