Macrophages and Treatment-Resistant NVAMD

 应聘者描述(由申请者提供)：应聘者是一名视网膜临床科学家，其主要职业目标是通过(1)阐明疾病机制，特别是巨噬细胞；以及(2)确定新的疾病生物标记物和治疗目标，促进对老年性黄斑变性(AMD)患者的护理。除了临床培训，他还完成了临床研究奖学金，并在科室K12职业发展计划中度过了两年。在第一年，他在不同的实验室轮换，第二年，他进行了一个新的项目，调查激活的巨噬细胞在新生血管重塑(NVR)中的作用，新生毛细血管转变为具有血管周围纤维化的分支小动脉，以及治疗难治性新生AMD(NVAMD)的主要原因。在目前的提案中，他的直接职业发展目标是通过鉴定产生促进NVR的巨噬细胞的特定血液单核细胞亚群(S)，以及通过表征在NVR环境中调节巨噬细胞效应功能的机制，进一步了解NVR的病理生物学。候选人计划在第三年早些时候提交一份R01报告，这是一个创新的翻译项目，旨在描述实验性CNV和NVAMD中巨噬细胞介导的NVR的生物学特征，将单核细胞亚群频率和激活状态与CNV形态和耐药NVAMD相关联。在获奖期间，还将获得免疫学、分子生物学、显微镜、系级研究研讨会和先进的负责任的研究行为方面的额外教学培训，候选人将在全国会议上展示他的发现，并提交他的作品供出版。环境：咨询委员会的指导和专业知识，杜克大学眼科和药理学/癌症生物学系的广泛资源，以及重要的机构承诺，将为这位候选人完成拟议的研究项目并成功过渡到独立的研究生涯提供所需的支持。研究：尽管玻璃体内抗血管内皮生长因子治疗改善了视力结果，但40-50%的患者表现出治疗耐药的NVAMD/PDA。在CNV形态反映NVR的患者中，PDA更常见。这位候选人和他的主要导师已经建立了巨噬细胞作为NVR的驱动细胞，初步数据表明，在激光诱导的CNV小鼠模型中，低级别全身暴露于三种不同的病原体相关分子模式(PAMPs)会促进NVR。尽管每个PAMP都有一个不同的激活受体，但所有三个PAMP激活的信号级联都能动员钙并激活钙结合蛋白钙调蛋白。因此，初步数据表明，钙/钙调蛋白依赖的蛋白激酶2(CAMKK2)的小鼠表现出NVR降低。CAMKK2是一种已知的放大巨噬细胞中PAMP激活的效应通路的中间激酶。中心假说是PAMP刺激通过激活CAMKK2介导的巨噬细胞效应功能来调节NVR。具体来说，低级别的PAMP刺激被假设为(1)增加血液中循环的非经典Ly6Clo单核细胞的频率；(2)促进Ly6Clo单核细胞来源的巨噬细胞的激活，增加纤维化生长因子的表达，(3)通过激活CAMKK2信号(图2)。纤维化因子招募和激活血管平滑肌细胞和肌成纤维细胞，导致NVR的发展。目的1提出PAMP在实验性新生血管中刺激NVR是由非经典的Ly6Clo单核细胞产生的活化巨噬细胞介导的假说。目的2将阐述CAMKK2调节巨噬细胞介导的NVR的假说。

 DESCRIPTION (provided by applicant): The candidate is a retina clinician-scientist whose primary career goal is to advance the care of patients with age-related macular degeneration (AMD) by (1) elucidating disease mechanisms, with a specific focus on macrophages; and (2) identifying novel disease biomarkers and targets for therapy. In addition to clinical training, he has completed a clinical research fellowship and has spent two years in a Departmental K12 Career Development Program. In the first year, he rotated through various laboratories and in the second year, he has pursued a novel project investigating the role of activated macrophages in neovascular remodeling (NVR), the transformation of nascent capillaries into branching arterioles with perivascular fibrosis, and a major cause of treatment-resistant neovascular AMD (NVAMD). His immediate career development goals in the current proposal are to further understanding of NVR pathobiology by identifying the specific blood monocyte subset(s) that give rise to NVR-promoting macrophages and by characterizing mechanisms that regulate macrophage effector function in the setting of NVR. The candidate plans an R01 submission in early year three on an innovative translational project to characterize the biology of macrophage-mediated NVR in experimental CNV and NVAMD, correlating monocyte subset frequencies and activation states with CNV morphology and treatment-resistant NVAMD. Additional didactic training in immunology, molecular biology, microscopy, departmental research seminars, and advanced responsible conduct of research will be obtained during the award period, and the candidate will present his findings at national meetings and submit his work for publication. Environment: The mentorship and expertise of the advisory committee, the extensive resources of the Duke Departments of Ophthalmology and Pharmacology / Cancer Biology, and the significant institutional commitment will provide the support needed for this candidate to complete the proposed research project and transition successfully to an independent research career. Research: Although intravitreal anti-VEGF therapies have improved vision outcomes, 40-50% of patients exhibit treatment-resistant NVAMD / PDA. PDA occurs more frequently in patients with CNV morphology that reflects NVR. The candidate and his primary mentor have established macrophages as a driver of NVR, and preliminary data suggests that low-grade systemic exposure to three different pathogen-associated molecular patterns (PAMPs) promotes NVR in a murine model of laser-induced CNV. In spite of each PAMP having a distinct activating receptor, all three PAMP-activated signaling cascades are known to mobilize calcium and activate the calcium-binding protein, calmodulin. Accordingly, preliminary data suggests that mice null for calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), an intermediate kinase known to amplify PAMP-activated effector pathways in macrophages, demonstrate reduced NVR. The central hypothesis is that PAMP-stimulation regulates NVR through activation of CaMKK2-mediated macrophage effector function. Specifically, low-grade PAMP stimulation is hypothesized to (1) increase the frequency of circulating nonclassical Ly6Clo monocytes in blood; and (2) promotes activation of Ly6Clo monocyte-derived macrophages, increasing expression of fibrogenic growth factors, (3) via activation of CaMKK2 signaling (Fig. 2). Fibrogenic factors recruit and activate vascular smooth muscle cells and myofibroblasts, leading to development of NVR. Aim 1 will address the hypothesis that PAMP-stimulated NVR in experimental neovascularization is mediated by activated macrophages arising from nonclassical Ly6Clo blood monocytes. Aim 2 will address the hypothesis that CaMKK2 regulates macrophage-mediated NVR.