Department of Nephrology, Research Institute for Medical Innovations, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands.
Department of Medical Biosciences, Research Institute for Medical Innovations, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands.
Biosensors (Basel). 2023 Mar 3;13(3):339. doi: 10.3390/bios13030339.
Crosstalk between glomerular endothelial cells and glomerular epithelial cells (podocytes) is increasingly becoming apparent as a crucial mechanism to maintain the integrity of the glomerular filtration barrier. However, studies directly investigating the effect of this crosstalk on the glomerular filtration barrier are scarce because of the lack of suitable experimental models. Therefore, we developed a custom-made glomerulus-on-a-chip model recapitulating the glomerular filtration barrier, in which we investigated the effects of co-culture of glomerular endothelial cells and podocytes on filtration barrier function and the phenotype of these respective cell types. The custom-made glomerulus-on-a-chip model was designed using soft lithography. The chip consisted of two parallel microfluidic channels separated by a semi-permeable polycarbonate membrane. The glycocalyx was visualized by wheat germ agglutinin staining and the barrier integrity of the glomerulus-on-a-chip model was determined by measuring the transport rate of fluorescently labelled dextran from the top to the bottom channel. The effect of crosstalk on the transcriptome of glomerular endothelial cells and podocytes was investigated via RNA-sequencing. Glomerular endothelial cells and podocytes were successfully cultured on opposite sides of the membrane in our glomerulus-on-a-chip model using a polydopamine and collagen A double coating. Barrier integrity of the chip model was significantly improved when glomerular endothelial cells were co-cultured with podocytes compared to monocultures of either glomerular endothelial cells or podocytes. Co-culture enlarged the surface area of podocyte foot processes and increased the thickness of the glycocalyx. RNA-sequencing analysis revealed the regulation of cellular pathways involved in cellular differentiation and cellular adhesion as a result of the interaction between glomerular endothelial cells and podocytes. We present a novel custom-made glomerulus-on-a-chip co-culture model and demonstrated for the first time using a glomerulus-on-a-chip model that co-culture affects the morphology and transcriptional phenotype of glomerular endothelial cells and podocytes. Moreover, we showed that co-culture improves barrier function as a relevant functional readout for clinical translation. This model can be used in future studies to investigate specific glomerular paracrine pathways and unravel the role of glomerular crosstalk in glomerular (patho) physiology.
肾小球内皮细胞和肾小球上皮细胞（足细胞）之间的串扰作为维持肾小球滤过屏障完整性的关键机制日益明显。然而，由于缺乏合适的实验模型，直接研究这种串扰对肾小球滤过屏障的影响的研究很少。因此，我们开发了一种定制的肾小球芯片模型，该模型再现了肾小球滤过屏障，我们在该模型中研究了肾小球内皮细胞和足细胞共培养对滤过屏障功能和这些细胞类型表型的影响。定制的肾小球芯片模型是使用软光刻技术设计的。该芯片由两个平行的微流道组成，由半透性聚碳酸酯膜隔开。通过麦胚凝集素染色可视化糖萼，通过测量荧光标记的葡聚糖从顶部通道到底部通道的转运率来确定肾小球芯片模型的屏障完整性。通过 RNA 测序研究串扰对肾小球内皮细胞和足细胞转录组的影响。我们使用聚多巴胺和胶原 A 双重涂层成功地在芯片的膜的两侧培养肾小球内皮细胞和足细胞。与肾小球内皮细胞或足细胞的单核培养相比，当肾小球内皮细胞与足细胞共培养时，芯片模型的屏障完整性显著提高。共培养使足细胞足突的表面积增大，并增加了糖萼的厚度。RNA 测序分析显示，由于肾小球内皮细胞和足细胞之间的相互作用，参与细胞分化和细胞黏附的细胞途径被调节。我们提出了一种新颖的定制肾小球芯片共培养模型，并首次使用肾小球芯片模型证明共培养影响肾小球内皮细胞和足细胞的形态和转录表型。此外，我们表明共培养改善了屏障功能，这是一个与临床转化相关的功能读出。该模型可用于未来的研究，以研究特定的肾小球旁分泌途径，并揭示肾小球串扰在肾小球（病理）生理学中的作用。
