{"title":"APP-CD74 轴介导内皮细胞与巨噬细胞的交流,促进肾损伤和肾纤维化。","authors":"Bin Liu, Faping Li, Yuxiong Wang, Xin Gao, Yunkuo Li, Yishu Wang, Honglan Zhou","doi":"10.3389/fphar.2024.1437113","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Kidney injuries often carry a grim prognosis, marked by fibrosis development, renal function loss, and macrophage involvement. Despite extensive research on macrophage polarization and its effects on other cells, like fibroblasts, limited attention has been paid to the influence of non-immune cells on macrophages. This study aims to address this gap by shedding light on the intricate dynamics and diversity of macrophages during renal injury and repair.</p><p><strong>Methods: </strong>During the initial research phase, the complexity of intercellular communication in the context of kidney injury was revealed using a publicly available single-cell RNA sequencing library of the unilateral ureteral obstruction (UUO) model. Subsequently, we confirmed our findings using an independent dataset from a renal ischemia-reperfusion injury (IRI) model. We treated two different types of endothelial cells with TGF-β and co-cultured their supernatants with macrophages, establishing an endothelial cell and macrophage co-culture system. We also established a UUO and an IRI mouse model. Western blot analysis, flow cytometry, immunohistochemistry and immunofluorescence staining were used to validate our results at multiple levels.</p><p><strong>Results: </strong>Our analysis revealed significant changes in the heterogeneity of macrophage subsets during both injury processes. Amyloid β precursor protein (APP)-CD74 axis mediated endothelial-macrophage intercellular communication plays a dominant role. In the <i>in vitro</i> co-culture system, TGF-β triggers endothelial APP expression, which subsequently enhances CD74 expression in macrophages. Flow cytometry corroborated these findings. Additionally, APP and CD74 expression were significantly increased in the UUO and IRI mouse models. Immunofluorescence techniques demonstrated the co-localization of F4/80 and CD74 <i>in vivo</i>.</p><p><strong>Conclusion: </strong>Our study unravels a compelling molecular mechanism, elucidating how endothelium-mediated regulation shapes macrophage function during renal repair. The identified APP-CD74 signaling axis emerges as a promising target for optimizing renal recovery post-injury and preventing the progression of chronic kidney disease.</p>","PeriodicalId":12491,"journal":{"name":"Frontiers in Pharmacology","volume":null,"pages":null},"PeriodicalIF":4.4000,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11439715/pdf/","citationCount":"0","resultStr":"{\"title\":\"APP-CD74 axis mediates endothelial cell-macrophage communication to promote kidney injury and fibrosis.\",\"authors\":\"Bin Liu, Faping Li, Yuxiong Wang, Xin Gao, Yunkuo Li, Yishu Wang, Honglan Zhou\",\"doi\":\"10.3389/fphar.2024.1437113\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Background: </strong>Kidney injuries often carry a grim prognosis, marked by fibrosis development, renal function loss, and macrophage involvement. Despite extensive research on macrophage polarization and its effects on other cells, like fibroblasts, limited attention has been paid to the influence of non-immune cells on macrophages. This study aims to address this gap by shedding light on the intricate dynamics and diversity of macrophages during renal injury and repair.</p><p><strong>Methods: </strong>During the initial research phase, the complexity of intercellular communication in the context of kidney injury was revealed using a publicly available single-cell RNA sequencing library of the unilateral ureteral obstruction (UUO) model. Subsequently, we confirmed our findings using an independent dataset from a renal ischemia-reperfusion injury (IRI) model. We treated two different types of endothelial cells with TGF-β and co-cultured their supernatants with macrophages, establishing an endothelial cell and macrophage co-culture system. We also established a UUO and an IRI mouse model. Western blot analysis, flow cytometry, immunohistochemistry and immunofluorescence staining were used to validate our results at multiple levels.</p><p><strong>Results: </strong>Our analysis revealed significant changes in the heterogeneity of macrophage subsets during both injury processes. Amyloid β precursor protein (APP)-CD74 axis mediated endothelial-macrophage intercellular communication plays a dominant role. In the <i>in vitro</i> co-culture system, TGF-β triggers endothelial APP expression, which subsequently enhances CD74 expression in macrophages. Flow cytometry corroborated these findings. Additionally, APP and CD74 expression were significantly increased in the UUO and IRI mouse models. Immunofluorescence techniques demonstrated the co-localization of F4/80 and CD74 <i>in vivo</i>.</p><p><strong>Conclusion: </strong>Our study unravels a compelling molecular mechanism, elucidating how endothelium-mediated regulation shapes macrophage function during renal repair. The identified APP-CD74 signaling axis emerges as a promising target for optimizing renal recovery post-injury and preventing the progression of chronic kidney disease.</p>\",\"PeriodicalId\":12491,\"journal\":{\"name\":\"Frontiers in Pharmacology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.4000,\"publicationDate\":\"2024-09-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11439715/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Frontiers in Pharmacology\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.3389/fphar.2024.1437113\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2024/1/1 0:00:00\",\"PubModel\":\"eCollection\",\"JCR\":\"Q1\",\"JCRName\":\"PHARMACOLOGY & PHARMACY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers in Pharmacology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.3389/fphar.2024.1437113","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/1/1 0:00:00","PubModel":"eCollection","JCR":"Q1","JCRName":"PHARMACOLOGY & PHARMACY","Score":null,"Total":0}
引用次数: 0
摘要
背景:肾脏损伤的预后往往很糟糕,其特点是纤维化发展、肾功能丧失和巨噬细胞参与。尽管对巨噬细胞极化及其对成纤维细胞等其他细胞的影响进行了广泛的研究,但人们对非免疫细胞对巨噬细胞的影响关注有限。本研究旨在通过揭示肾损伤和修复过程中巨噬细胞的复杂动态和多样性来弥补这一空白:在最初的研究阶段,我们利用公开的单侧输尿管梗阻(UUO)模型单细胞 RNA 测序文库揭示了肾损伤过程中细胞间通讯的复杂性。随后,我们利用来自肾缺血再灌注损伤(IRI)模型的独立数据集证实了我们的发现。我们用 TGF-β 处理了两种不同类型的内皮细胞,并将其上清液与巨噬细胞共培养,建立了内皮细胞与巨噬细胞共培养系统。我们还建立了 UUO 和 IRI 小鼠模型。我们采用了 Western 印迹分析、流式细胞术、免疫组织化学和免疫荧光染色等方法,从多个层面验证了我们的研究结果:结果:我们的分析表明,在两种损伤过程中,巨噬细胞亚群的异质性都发生了显著变化。淀粉样β前体蛋白(APP)-CD74轴介导的内皮-巨噬细胞细胞间通讯起着主导作用。在体外共培养系统中,TGF-β会触发内皮细胞APP的表达,进而增强巨噬细胞中CD74的表达。流式细胞仪证实了这些发现。此外,在 UUO 和 IRI 小鼠模型中,APP 和 CD74 的表达明显增加。免疫荧光技术证明了F4/80和CD74在体内的共定位:我们的研究揭示了一种令人信服的分子机制,阐明了肾脏修复过程中内皮介导的调节如何影响巨噬细胞的功能。已确定的 APP-CD74 信号轴是优化损伤后肾脏恢复和预防慢性肾脏疾病进展的一个有前景的靶点。
APP-CD74 axis mediates endothelial cell-macrophage communication to promote kidney injury and fibrosis.
Background: Kidney injuries often carry a grim prognosis, marked by fibrosis development, renal function loss, and macrophage involvement. Despite extensive research on macrophage polarization and its effects on other cells, like fibroblasts, limited attention has been paid to the influence of non-immune cells on macrophages. This study aims to address this gap by shedding light on the intricate dynamics and diversity of macrophages during renal injury and repair.
Methods: During the initial research phase, the complexity of intercellular communication in the context of kidney injury was revealed using a publicly available single-cell RNA sequencing library of the unilateral ureteral obstruction (UUO) model. Subsequently, we confirmed our findings using an independent dataset from a renal ischemia-reperfusion injury (IRI) model. We treated two different types of endothelial cells with TGF-β and co-cultured their supernatants with macrophages, establishing an endothelial cell and macrophage co-culture system. We also established a UUO and an IRI mouse model. Western blot analysis, flow cytometry, immunohistochemistry and immunofluorescence staining were used to validate our results at multiple levels.
Results: Our analysis revealed significant changes in the heterogeneity of macrophage subsets during both injury processes. Amyloid β precursor protein (APP)-CD74 axis mediated endothelial-macrophage intercellular communication plays a dominant role. In the in vitro co-culture system, TGF-β triggers endothelial APP expression, which subsequently enhances CD74 expression in macrophages. Flow cytometry corroborated these findings. Additionally, APP and CD74 expression were significantly increased in the UUO and IRI mouse models. Immunofluorescence techniques demonstrated the co-localization of F4/80 and CD74 in vivo.
Conclusion: Our study unravels a compelling molecular mechanism, elucidating how endothelium-mediated regulation shapes macrophage function during renal repair. The identified APP-CD74 signaling axis emerges as a promising target for optimizing renal recovery post-injury and preventing the progression of chronic kidney disease.
期刊介绍:
Frontiers in Pharmacology is a leading journal in its field, publishing rigorously peer-reviewed research across disciplines, including basic and clinical pharmacology, medicinal chemistry, pharmacy and toxicology. Field Chief Editor Heike Wulff at UC Davis is supported by an outstanding Editorial Board of international researchers. This multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, clinicians and the public worldwide.