Enhancement of Renal Epithelial Cell Functions through Microfluidic-Based Coculture with Adipose-Derived Stem Cells

Abstract

Current hemodialysis has functional limitations and is insufficient for renal transplantation. The bioartificial tubule device has been developed to contribute to metabolic functions by implanting renal epithelial cells into hollow tubes and showed a higher survival rate in acute kidney injury patients. In healthy kidney, epithelial cells are surrounded by various types of cells that interact with extracellular matrices, which are primarily composed of laminin and collagen. The current study developed a microfluidic coculture platform to enhance epithelial cell function in bioartificial microenvironments with multiple microfluidic channels that are microfabricated by polydimethylsiloxane. Collagen gel (CG) encapsulated with adipose-derived stem cells (CG-ASC) was injected into a central microfluidic channel for three-dimensional (3D) culture. The resuspended Madin-Darby canine kidney (MDCK) cells were injected into nascent channels and formed an epithelial monolayer. In comparison to coculture different cells using the commercial transwell system, the current coculture device allowed living cell monitoring of both the MDCK epithelial monolayer and CG-ASC in a 3D microenvironment. By coculture with CG-ASC, the cell height was increased with columnar shapes in MDCK. Promotion of cilia formation and functional expression of the ion transport protein in MDCK were also observed in the cocultured microfluidic device. When applying fluid flow, the intracellular protein dynamics can be monitored in the current platform by using the time-lapse confocal microscopy and transfection of GFP-tubulin plasmid in MDCK. Thus, this microfluidic coculture device provides the renal epithelial cells with both morphological and functional improvements that may avail to develop bioartificial renal chips.

Microfluidic 3D cell culture: from tools to tissue models

“…A collagen microfluidic structure was used to pattern a tube of Madin-Darby canine kidney (MDCK) cells, next to a tube of human umbilical vein endothelial cells (HUVEC) [45]. Huang et al also show a perfusable, stratified MDCK co-culture with adipose derived stem cells [46], which enhanced cilia formation and increased expression of ion transporters of the MDCK cells.…”

Biology-inspired microphysiological system approaches to solve the prediction dilemma of substance testing

“…Other organs models in single-organ MPS include the small artery (Günter et al, 2010), the nervous system (Booth and Kim, 2012; Brown et al, 2014; Kermanet al, 2015; Nery et al, 2015; Park et al, 2009; Robertson et al, 2014; Taylor et al, 2005), the pancreas (Silva et al, 2013; Jun et al, 2013; Lee et al, 2012), the kidney (Snouber et al, 2012; Snouber et al, 2011; Jang et al, 2013; Ferrell et al, 2012; Kim and Takayama, 2015; Huang et al, 2013; Mu et al, 2013), the bone-marrow (Cui et al, 2007), the skin and hair (Atac et al, 2013) and the intestine (Esch et al, 2012 ; Kim and Ingber, 2013; Kim et al, 2012; Kim et al, 2013; Kimura et al, 2008; Lahar et al, 2011; Mahler et al, 2009; McAuliffe et al, 2008; Ootani et al, 2010; Sato et al, 2009; Sung et al, 2011; Yu et al, 2012) at different levels of biological complexity. Gao and colleagues (2013) designed an integrated microfluidic device directly coupled to a mass spectrometer, for instance, to characterize drug permeability of the intestinal barrier in a real-time manner.…”

A Role for 3D Printing in Kidney-on-a-Chip Platforms

“…To model kidney epithelial cells, Huang and Wu et al . created a single-layer microfluidic system for co-culturing Madin-Darby canine kidney (MDCK) epithelial cells with collagen gel-embedded adipose stem cells (ASCs) [56]. There was a 35% increase in cellular height (with columnar shape), promotion of cilia formation, and increased Na/K ATPase expression [56].…”

“…created a single-layer microfluidic system for co-culturing Madin-Darby canine kidney (MDCK) epithelial cells with collagen gel-embedded adipose stem cells (ASCs) [56]. There was a 35% increase in cellular height (with columnar shape), promotion of cilia formation, and increased Na/K ATPase expression [56]. It should be recognized, however, that MDCK cells have characteristics of the distal nephron, which make up a much smaller part of the tubule than does the proximal tubule (which comprises approximately 90% of the mass of the kidney cortex).…”

“…The combination of surface topography and fluidic shear stress not only promoted cell alignment in the direction of the groove lines and flow, but also enhanced tight junction formation for seeded HK-2 cells [58]. In general improved physiologic behavior of kidney cells in response to applied fluidic shear stress were consistently found by multiple groups in many experiments [56–58]. …”