Enrichment of ATP Binding Proteins Unveils Proteomic Alterations in Human Macrophage Cell Death, Inflammatory Response, and Protein Synthesis after Interaction with <i>Candida albicans</i>

Macrophages are involved in the primary human response to Candida albicans. After pathogen recognition, signaling pathways are activated, leading to the production of cytokines, chemokines, and antimicrobial peptides. ATP binding proteins are crucial for this regulation. Here, a quantitative proteomic and phosphoproteomic approach was carried out for the study of human macrophage ATP-binding proteins after interaction with C. albicans. From a total of 547 nonredundant quantified proteins, 137 were ATP binding proteins and 59 were detected as differentially abundant. From the differentially abundant ATP-binding proteins, 6 were kinases (MAP2K2, SYK, STK3, MAP3K2, NDKA, and SRPK1), most of them involved in signaling pathways. Furthermore, 85 phosphopeptides were quantified. Macrophage proteomic alterations including an increase of protein synthesis with a consistent decrease in proteolysis were observed. Besides, macrophages showed changes in proteins of endosomal trafficking together with mitochondrial proteins, including some involved in the response to oxidative stress. Regarding cell death mechanisms, an increase of antiapoptotic over pro-apoptotic signals is suggested. Furthermore, a high pro-inflammatory response was detected, together with no upregulation of key mi-RNAs involved in the negative feedback of this response. These findings illustrate a strategy to deepen the knowledge of the complex interactions between the host and the clinically important pathogen C. albicans.巨噬细胞（Macrophages）参与人体对白色念珠菌（Candida albicans）的初次免疫应答。病原体被识别后，相关信号通路被激活，进而介导细胞因子、趋化因子及抗菌肽的产生。ATP结合蛋白（ATP binding proteins）在这一调控过程中发挥关键作用。本研究采用定量蛋白质组学与磷酸化蛋白质组学联合分析策略，探究了人类巨噬细胞与白色念珠菌（C. albicans）相互作用后其ATP结合蛋白的表达变化情况。本次分析共鉴定到547个非冗余定量蛋白质，其中137个为ATP结合蛋白，另有59个呈现丰度差异显著的变化。在丰度差异显著的ATP结合蛋白中，包含6种激酶（MAP2K2、SYK、STK3、MAP3K2、NDKA及SRPK1），其中多数参与信号通路的调控。此外，本研究共定量到85个磷酸肽。研究观察到巨噬细胞的蛋白质组发生显著改变：蛋白质合成水平上升，而蛋白水解过程持续减弱。同时，巨噬细胞的内体转运相关蛋白及线粒体蛋白均出现表达变化，其中部分蛋白参与氧化应激应答。就细胞死亡机制而言，研究提示抗凋亡信号相较于促凋亡信号显著增强。此外，本研究检测到强烈的促炎应答，且未观察到参与该应答负反馈调控的关键微小RNA（miRNA）的表达上调。上述研究结果为深化宿主与临床重要病原体白色念珠菌间复杂相互作用的认知提供了可行策略。