Kim-1 regulation of autophagy and MHC presentation in kidney injury

描述（由申请人提供）：拟议工作的总体目标是更好地了解Kim-1介导的吞噬作用在肾损伤中的作用。长期目标是确定Kim-1介导的潜在调节机制，其可用作改善肾损伤的靶点。具体来说，我们将使用在体外和体内技术来描绘的机制，金-1调节自噬和金-1介导的自噬对MHC II类呈递的影响。在我们的第一个具体目标中，目标是确定Kim-1上调自噬并将吞噬物质靶向自噬体的机制。利用化学和遗传学方法，我们将研究运输金-1阳性吞噬体的自噬体。我们还将确定Kim-1的胞质尾是否将吞噬碎片靶向自噬体。最后，我们将检查Kim-1胞质尾是否将吞噬体靶向自噬体。在第二个具体的目标，我们将检查是否金-1诱导的自噬导致MHC II类呈递的肽从吞噬碎片。我们将使用不表达Kim-1、表达Kim-1或表达吞噬作用无效突变体的两种模型细胞和野生型小鼠或表达吞噬作用无效Kim- 1的小鼠来解决这一问题。首先，我们将Kim-1与细胞培养物和受损肾脏中的自噬体和MHC抗原加工区室共定位。然后，我们将比较暴露于吞噬目标后，肽对MHC II类的呈递。最后，我们将研究自噬是否是表达Kim-1的小管细胞在吞噬作用后激活T细胞所必需的。相关性：急性肾损伤仍然是一种与高发病率和死亡率相关的主要肾脏疾病。在过去十年中，阿基的发病率一直在稳步增加，预计还会进一步增加。肾衰竭患者的死亡率通常为30- 50%。虽然研究已经导致了许多治疗方案和提高生存率，但需要更多的研究来找到解决这个问题的方法。我们的研究旨在更好地了解一种蛋白质（Kim-1）的功能，这种蛋白质与大多数形式的肾衰竭有关。我们将确定Kim-1是否有助于在肾损伤中观察到的自噬和MHC呈递，并确定治疗干预的潜在靶点。 公共卫生相关性：急性肾损伤仍然是一种与高发病率和死亡率相关的主要肾脏疾病。在过去十年中，阿基的发病率一直在稳步增加，预计还会进一步增加。肾衰竭患者的死亡率通常为30- 50%。虽然研究已经导致了许多治疗方案和提高生存率，但需要更多的研究来找到解决这个问题的方法。我们的研究旨在更好地了解一种蛋白质（Kim-1）的功能，这种蛋白质与大多数形式的肾衰竭有关。我们将确定Kim-1如何调节自噬，以及这种自噬是否有助于肾损伤中观察到的炎症，并确定治疗干预的潜在靶点。

DESCRIPTION (provided by applicant): The overarching goal of the proposed work is to better understand the role of Kim-1 mediated phagocytosis in kidney injury. The long term goal is to identify potential regulatory mechanisms mediated by Kim-1 which could be used as targets to ameliorate kidney injury. Specifically, we will use in vitro and in vivo techniques to delineate the mechanism by which Kim-1 regulates autophagy and the effect Kim-1 mediated autophagy has on MHC class II presentation. In our first specific aim, the goal is to identify the mechanism by which Kim-1 upregulates autophagy and targets phagocytosed material to the autophagosome. Using chemical and genetic methods we will examine the trafficking of Kim-1 positive phagosomes to the autophagosome. We will also determine whether the cytoplasmic tail of Kim-1 targets phagocytosed debris to the autophagosome. Finally, we will examine whether Kim-1 cytoplasmic tail targets the phagosome to the autophagosome. In the second specific aim, we will examine whether Kim-1 induced autophagy leads to MHC class II presentation of peptides from the phagocytosed debris. We will approach this using two models cells not expressing Kim-1, expressing Kim-1 or expressing a phagocytosis null mutant and wt mice or mice expressing a phagocytosis null Kim- 1. First, we will co-localize Kim-1 with the autophagosome and MHC antigen processing compartment in cell culture and injured kidneys. We will then compare the presentation of peptides on MHC class II, following exposure to phagocytic targets. Finally, we will examine whether autophagy is necessary for Kim-1 expressing tubule cells to activate T-cells following phagocytosis. Relevance: Acute kidney injury remains a major kidney disease associated with high morbidity and mortality. The incidence of AKI has been steadily increasing over the past decade and is expected to increase further. The mortality rate of patients diagnosed with kidney failure is often 30-50%. Although research has lead to many treatment options and increased survivability, more research is needed to find a solution to this problem. Our study is aimed at better understanding the function of a protein (Kim-1) which is found associated with most forms of kidney failure. We will determine whether Kim-1 contributes to the autophagy and MHC presentation observed in kidney injury as well as identify potential targets for therapeutic intervention. PUBLIC HEALTH RELEVANCE: Acute kidney injury remains a major kidney disease associated with high morbidity and mortality. The incidence of AKI has been steadily increasing over the past decade and is expected to increase further. The mortality rate of patients diagnosed with kidney failure is often 30-50%. Although research has lead to many treatment options and increased survivability, more research is needed to find a solution to this problem. Our study is aimed at better understanding the function of a protein (Kim-1) which is found associated with most forms of kidney failure. We will determine how Kim-1 regulates autophagy and whether this autophagy contributes to the inflammation observed in kidney injury as well as identifies potential targets for therapeutic intervention.