Targeting Entry Pathways in Leishmaniasis

描述（由申请人提供）：候选人/培训：我的目标是这个职业奖是获得必要的培训，成为一个独立的研究人员在利什曼原虫感染的分子发病机制。我是一名儿科传染病研究员，在微生物学上研究寄生虫弓形虫在我的研究期间，我开始研究调节巨噬细胞摄取利什曼原虫的机制。我的博士在我的奖学金培训期间，我积累了关于发病机制的小鼠模型的经验。我现在计划在生物化学和药理学方面发展更多的专业知识和指导研究经验，并将其与利什曼病的发病机制和治疗联系起来。我的导师是一位生物化学家，研究调节肌动蛋白聚合的机制。我还将由一位在利什曼原虫感染及其通过小鼠免疫系统调节方面具有丰富经验的寄生虫学家，一位致力于整合素激活机制的细胞生物学家和一位药理学家指导。我以前的研究背景，我的临床培训，我的研究在我的奖学金，我的指导研究和课程的K 08奖期间相结合，将提高我的知识的科学广度，并独特地使我能够为分子寄生虫学领域作出贡献。 项目：利什曼原虫是一种寄生虫，导致皮肤或内脏疾病。目前的疗法有显著的副作用，寄生虫正在对它们产生抗药性，因此需要新的疗法。利什曼原虫必须生活在吞噬细胞内才能生存。两个生命周期阶段，前鞭毛体和无鞭毛体，感染巨噬细胞。研究利什曼原虫如何被巨噬细胞吞噬将有助于我们了解其发病机制，并可以确定新的抗寄生虫靶点。我的工作表明，Abl家族激酶允许巨噬细胞摄取利什曼原虫，抑制这些激酶可改善小鼠的利什曼病。该项目进一步定义了利什曼原虫被巨噬细胞吞噬并导致疾病的机制，最终目标是抑制摄取的药物将提供新的治疗策略。我假设1）2整合素和Abl之间的相互作用允许巨噬细胞摄取前鞭毛体，2）FcR，Src家族激酶和Arg之间的相互作用允许巨噬细胞摄取无鞭毛体，3）可以抑制这些信号蛋白的药物将减少小鼠皮肤利什曼病的表现。在具体目标1中，我将描述<$2整合素：Abl相互作用及其在巨噬细胞摄取前鞭毛体过程中的作用。在具体目标2中，我将确定Src家族激酶如何影响巨噬细胞对无鞭毛体的摄取以及小鼠皮肤利什曼病的严重程度。在具体目标3中，我将评估 巨噬细胞单独或与米替福新组合的寄生虫摄取降低了小鼠皮肤利什曼病的严重性。我的研究将阐明寄生虫摄取的最初步骤，提高我们对利什曼病发病机制的理解，并提供治疗这种毁灭性感染的新方法。

DESCRIPTION (provided by applicant): CANDIDATE/TRAINING: My goal for this career award is to obtain the necessary training to become an independent investigator in the molecular pathogenesis of Leishmania infection. I am a pediatric infectious diseases fellow who earned a Ph.D. in microbiology studying the parasite Toxoplasma gondii. During my fellowship, I began to study the mechanisms that regulate the uptake of Leishmania by macrophages. My Ph.D. provided me with experience in microbiology and cell biology, and I developed experience with mouse models of pathogenesis during my fellowship training. I now plan to develop additional expertise and mentored research experience in biochemistry and pharmacology, and relate it to the pathogenesis and treatment of leishmaniasis. My mentor is a biochemist who studies the mechanisms that regulate actin polymerization. I will also be mentored by a parasitologist with extensive experience in Leishmania infection and its regulation by the mouse immune system, a cell biologist who works on the mechanisms of integrin activation, and a pharmacologist. The combination of my previous research background, my clinical training, my research during my fellowship, and my mentored research and coursework during the K08 award period will enhance my scientific breadth of knowledge, and uniquely enable me to contribute to the field of molecular parasitology. PROJECT: Leishmania is a parasite that causes cutaneous or visceral disease. Current therapies have significant side effects, and parasites are developing resistance to them, so new therapies are needed. Leishmania must live inside phagocytes to survive. Both life cycle stages, promastigotes and amastigotes, infect macrophages. Studying how Leishmania is engulfed by macrophages will help us understand its pathogenesis and could define new antiparasitic targets. My work shows that Abl family kinases permit uptake of Leishmania by macrophages, and that inhibiting these kinases ameliorates leishmaniasis in mice. This project further defines the mechanism by which Leishmania is engulfed by macrophages and causes disease, with the eventual goal that drugs that inhibit uptake will provide novel therapeutic strategies. I hypothesize 1) interactions between ¿2 integrin and Abl allow promastigote uptake by macrophages, 2) interactions among FcR, Src family kinases, and Arg allow amastigote uptake by macrophages, and 3) drugs that can inhibit these signaling proteins will decrease the manifestations of cutaneous leishmaniasis in mice. In Specific Aim 1, I will characterize the ¿2 integrin:Abl interaction and its role during promastigote uptake by macrophages. In Specific Aim 2, I will determine how Src family kinases affect amastigote uptake by macrophages and the severity of cutaneous leishmaniasis in mice. In Specific Aim 3, I will assess whether inhibitors of parasite uptake by macrophages, alone or in combination with miltefosine, decrease the severity of cutaneous leishmaniasis in mice. My studies will elucidate the initial steps of parasit uptake, improve our understanding of the pathogenesis of leishmaniasis, and provide novel approaches to treat this devastating infection.