Design and Implementation of a Simple In Vitro Microfluidic Platform for Culturing Kidney Tubular Cells in the Presence of Flow.

Fluid shear stress plays a vital role in regulating renal epithelial cell behavior in vivo . However, conventional static culture systems fail to recapitulate these mechanical cues. To address this limitation, we developed a simple two-dimensional (2D) microfluidic device to investigate the effects of shear stress on human proximal tubular cells (hPTCs). We have called this the NephroFlux Device . It was designed using AutoCAD and fabricated with polydimethylsiloxane (PDMS) via soft lithography, then bonded to glass coverslips using oxygen plasma treatment. Scanning electron microscopy (SEM) was used to observe morphological changes in apical structures such as microvilli and primary cilia within the device. Flow exposure within the NephroFlux device significantly improved cell proliferation and surface coverage compared with static conditions. In addition to increased density, cells exposed to flow were characterized by an increased microvillus density and elongated primary cilia. Collectively, these results establish NephroFlux as a practical tool for the application of flow, facilitating investigation of renal mechanobiology and providing a foundation for future applications in disease modeling, nephrotoxicity testing, and artificial organ development.