Targeting Pathogens at the Site of Cellular Entry

这项研究的长期目标是开发一种新的治疗方法，通过提供抗病毒药物、抗生素和疫苗的替代疗法，彻底改变治疗传染病的方式。布鲁氏菌病和结核病是野生和家养物种的主要传染病，目前尚无治愈或治疗方法。此外，动物是其他动物和人类传染病的主要来源。布鲁氏菌病是一种通过动物与人直接接触传播的人畜共患病。其他人畜共患病包括多诺瓦氏雷氏热、H5N1禽流感病毒和艾滋病毒。由于跨物种传播和抗生素耐药性，就医源性增强而言，跨物种病毒和细菌感染一直是一个值得关注的问题。众所周知，大多数病原体通过内吞作用侵入细胞，通过附着于现有的细胞表面受体。在细胞内，病原体欺骗核内体和溶酶体，并优先在它们内部分裂。在真核细胞中，新合成的蛋白质传递到核内体和溶酶体依赖于高尔基体，即分类和靶向蛋白质到这些目的地的细胞器。传递到核内体和溶酶体的蛋白质包括酶和激活蛋白。它们通过特殊的分选受体被引导到那里。最近，我们在溶酶体蛋白prosaposin中发现了一个区域，该区域包含一个基序，该基序与排序受体sortilin结合，并因此运输到核内体和溶酶体。在本研究中，我们将验证这样一个假设，即与该基序相关的融合蛋白可以通过sortilin转运到酶内/溶酶体腔室，并且该序列可能对靶向抗致病蛋白有用。我们的研究将允许建立一个新的策略的概念证明抗菌蛋白靶向内切酶/溶酶体室。我们的研究结果将与野生、濒危、家养动物以及人类传染病的治疗相关，并将开辟无数的途径来研究抗致病性肽在病毒、细菌和原虫感染中的传递和作用。

The long term objective of this research is to develop a novel therapeutic approach that will revolutionize the way transmissible diseases are treated, by offering an alternative therapy to antiviral drugs, antibiotics and vaccines. Brucellosis and tuberculosis, for which there are no cures or treatments, are major infectious agents in wild and domestic species. Furthermore, animals are major sources of infectious diseases to other animals and humans. Brucellosis is a zoonosis transmitted by direct animal-to-human contact. Other zoonoses include Leihsmania donovani, H5N1 avian influenza virus and HIV virus. Cross-species viral and bacterial infections are a constant preoccupation with respect to iatrogenic enhancement due to cross-species transmission and antibiotic resistance. It is well known that the majority of pathogens invade the cell via endocytosis, by attaching to existing cell surface receptors. Inside the cell, the pathogens trick the endosomes and lysosomes and preferentially divide within them. In eukaryotic cells the delivery of newly synthesized proteins to endosomes and lysosomes is dependent on the Golgi apparatus, i.e. the organelle that sorts and targets proteins to these destinations. Proteins delivered to endosomes and lysosomes include enzymes and activator proteins. They are directed therein via special sorting receptors. Recently, we identified a region in the lysosomal protein prosaposin that contains a motif required for its binding to the sorting receptors sortilin and consequently for its transport to endosomes and lysosomes. In this proposal we will test the hypothesis that fusion proteins linked to this motiff can be transported to the endo/lysosomal compartment via sortilin, and that this sequence may be useful for the targeting of anti-pathogenic proteins. Our study will permit to establish a proof of concept of a new strategy for the targeting of antimicrobial proteins to the endo/lysosomal compartment. The outcome of our research will be relevant for the treatment of infectious diseases in wild, endangered, and domestic animal species, as well as in humans, and will open innumerable avenues to examine the delivery and effects of antipathogenic peptides in viral, bacterial and protozoal infections.