BIOLOGY, IMMUNOLOGY & THERAPY OF ACANTHAMOEBA KERATITIS

生物学、免疫学

• 批准号: 6938504
• 负责人: Hassan Alizadeh
• 金额: $ 31.2万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6938504
• 关键词: Acanthamoeba; biological products; biotechnology; chronic disease /disorder; collagen; connective tissue cells; drug discovery /isolation; extracellular matrix; hamsters; intermolecular interaction; keratitis; metalloendopeptidases; molecular pathology; mucosal immunity; nonhuman therapy evaluation; oral administration; parasite infection mechanism; parasitic eye infections; plasminogen activator; plasminogen activator inhibitors; protein structure function; protozoal antigen; protozoal vaccine; vaccine development; vaccine evaluation

DESCRIPTION (provided by applicant): Acanthamoeba keratitis is a sight-threatening corneal disease caused by pathogenic free-living amoebae. The pathogenic cascade of Acanthamoeba keratitis involves a series of processes that include: (1) binding of the trophozoites to the corneal epithelial cells via lectin-glycoprotein interactions, (2) generation of cytopathic factors that destroy the corneal epithelium and stromal cells, (3) production of proteolytic enzymes that facilitate the invasion and penetration of trophozoites through the basement membrane and stroma, (4) elaboration of collagenolytic enzymes that degrade types I and IV collagens, which constitute the corneal matrix, (5) activation of corneal membrane metalloproteinases and, (6) induction of perineuritis. Stromal dissolution is a major blinding complication of Acanthamoeba keratitis. It will be important to determine what factors are involved in pathogenesis of stromal disease. In the present application, we are using different strategies to attack crucial steps in the pathogenic cascade in an effort to mitigate ongoing keratitis and preserve corneal tissues. Accordingly, therapeutic modalities are designed to inhibit invasion and destruction of corneal tissues after the organisms have invaded corneal matrix. The specific aims for this project are: 1) determine the role of Acanthamoeba plasminogen activator (aPA) in the pathogenesis of Acanthamoeba keratitis, 2) analyze the collagenolytic activity of the mannose-induced Acanthamoeba protein (133 -kDa), 3 ) determine if the mannose-induced Acanthamoeba protein (133-kDa) activate matrix metalloproteinases 4) determine feasibility of using the mannose-induced protein (133-kDa) and Acanthamoeba plasminogen activator (aPA) as immunogens for inducing immunity and mitigating the pathogenesis of Acanthamoeba infections. 5) Clone the 133-kDa protein and analyze the fragment that might be suitable for use as a subunit vaccine to induce better protection against Acanthamoeba infections. These studies utilize the Chinese hamster model of Acanthamoeba keratitis, that is similar to the human counterpart. Continued presence of Acanthamoeba keratitis and emergence of the drug resistant strains is underscoring the significance of this endeavor. The long-range goal of this project is to develop an anti-disease vaccine as a therapeutic adjunct for the management of Acanthamoeba keratitis.

描述（由申请人提供）：棘阿米巴角膜炎是一种由致病性自由生活阿米巴引起的威胁视力的角膜疾病。棘阿米巴角膜炎的致病级联涉及一系列过程，包括：（1）滋养体通过凝集素-糖蛋白相互作用与角膜上皮细胞结合，（2）产生破坏角膜上皮和基质细胞的细胞病变因子，（3） ）产生蛋白水解酶，促进滋养体通过基底膜和基质的侵袭和渗透，（4）详细阐述胶原蛋白分解酶降解构成角膜基质的 I 型和 IV 型胶原蛋白，(5) 激活角膜膜金属蛋白酶，(6) 诱导神经周围炎。基质溶解是棘阿米巴角膜炎的主要致盲并发症。确定哪些因素参与基质病的发病机制非常重要。在本申请中，我们使用不同的策略来攻击致病级联中的关键步骤，以减轻持续的角膜炎并保护角膜组织。因此，治疗方式被设计为在生物体侵入角膜基质后抑制角膜组织的侵入和破坏。该项目的具体目标是：1) 确定棘阿米巴纤溶酶原激活剂 (aPA) 在棘阿米巴角膜炎发病机制中的作用，2) 分析甘露糖诱导的棘阿米巴蛋白 (133 -kDa) 的胶原溶解活性，3) 确定是否甘露糖诱导的棘阿米巴蛋白 (133-kDa) 激活基质金属蛋白酶 4) 确定可行性使用甘露糖诱导蛋白（133-kDa）和棘阿米巴纤溶酶原激活剂（aPA）作为免疫原来诱导免疫并减轻棘阿米巴感染的发病机制。 5) 克隆 133-kDa 蛋白并分析可能适合用作亚单位疫苗的片段，以诱导更好的针对棘阿米巴感染的保护。这些研究利用了棘阿米巴角膜炎的中国仓鼠模型，该模型与人类类似。棘阿米巴角膜炎的持续存在和耐药菌株的出现凸显了这一努力的重要性。该项目的长期目标是开发一种抗病疫苗作为治疗棘阿米巴角膜炎的辅助治疗方法。