title: A microfluidic bioreactor with integrated transepithelial electrical resistance (TEER) measurement electrodes for evaluation of renal epithelial cells.
abstract: We have developed a bilayer microfluidic system with integrated transepithelial electrical resistance (TEER) measurement electrodes to evaluate kidney epithelial cells under physiologically relevant fluid flow conditions. The bioreactor consists of apical and basolateral fluidic chambers connected via a transparent microporous membrane. The top chamber contains microfluidic channels to perfuse the apical surface of the cells. The bottom chamber acts as a reservoir for transport across the cell layer and provides support for the membrane. TEER electrodes were integrated into the device to monitor cell growth and evaluate cell-cell tight junction integrity. Immunofluorescence staining was performed within the microchannels for ZO-1 tight junction protein and acetylated α-tubulin (primary cilia) using human renal epithelial cells (HREC) and MDCK cells. HREC were stained for cytoskeletal F-actin and exhibited disassembly of cytosolic F-actin stress fibers when exposed to shear stress. TEER was monitored over time under normal culture conditions and after disruption of the tight junctions using low Ca(2+) medium. The transport rate of a fluorescently labeled tracer molecule (FITC-inulin) was measured before and after Ca(2+) switch and a decrease in TEER corresponded with a large increase in paracellular inulin transport. This bioreactor design provides an instrumented platform with physiologically meaningful flow conditions to study various epithelial cell transport processes.
authors.affiliation: Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Ferrell
authors.forename: Ravi R
authors.initials: RR
authors.lastname: Desai
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Fleischman
authors.forename: Shuvo
authors.initials: S
authors.lastname: Roy
authors.forename: H David
authors.initials: HD
authors.lastname: Humes
authors.forename: William H
authors.initials: WH
authors.lastname: Fissell
mesh_terms: D000818:Animals; D019149:Bioreactors; D049109:Cell Proliferation; D004285:Dogs; D017097:Electric Impedance; D004566:Electrodes; D004847:Epithelial Cells / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D008565:Membrane Proteins / Q000032:analysis; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D010750:Phosphoproteins / Q000032:analysis; D013194:Staining and Labeling; D019108:Tight Junctions / Q000502:physiology; D014404:Tubulin / Q000032:analysis; D062826:Zonula Occludens-1 Protein
chemical_list: D008565:Membrane Proteins; D010750:Phosphoproteins; C569042:TJP1 protein, human; D014404:Tubulin; D062826:Zonula Occludens-1 Protein