Comparison of Conventional Methods with the Dynamic Impedance-Based Method for Monitoring Ethanol-Induced Epithelial Barrier Dysfunction
(A) The reversible barrier dysfunction induced by 7.5% ethanol was assessed by measuring phenol red permeability (control: untreated Caco-2 cell monolayer; EtOH: Caco-2 exposed in ethanol for 3 h; EtOH removal: Caco-2 exposed in ethanol for 3 h followed by replacing ethanol with fresh medium for another 3 h) and (B) TEER assay. (C) Dynamic impedance-based monitoring of ethanol (7.5%) induced epithelial barrier dysfunction, which was reversed after ethanol was removed. Black arrow: ethanol was added; gray arrow: ethanol was removed. (Data and figures adapted from Sun M, et. al., 2012).
Co-Culture of Astrocytes Enhanced the Barrier Function of Brain Microvascular Endothelial Cells (BMEC)
(A) Schematic of assembly of the inverted blood brain barrier model. Astrocytes and BMEC were grown on the transwell membrane in the upper chambers and on the gold electrode in lower chambers the CIM device, respectively. (B) Astrocytes (seeding densities were 0, 1000, 4000 and 8000/well) increased the CI of BMEC in a dose-dependent manner. (Data and figures adapted from Sansing HA, et. al., 2012).
Key Benefits of Using xCELLigence for Studying Cell Barrier Function:
- A label-free alternative to solute permeability and transendothelial electrical resistance (TEER) assays.
- Direct, sensitive, and quantitative.
- Real-time assay is conducted under normal tissue culture conditions, allowing for monitoring of barrier function disruption as well as recovery.
- Noninvasive nature of the readout allows for orthogonal assays conducted on the same device, including visual monitoring of cell density by microscopy.