Transport Properties Are Not Altered across Caco-2 Cells with Heightened TEER Despite Underlying Physiological and Ultrastructural Changes

Abstract

Selected properties of Caco-2 cells were examined after disparate transepithelial electrical resistance (TEER) measurements were observed in two populations of Caco-2 cells. Comparisons were made between the early passages of Caco-2 cells (Caco-2E, passages 35-47) and the later passages of cells (Caco-2L, passages 87-112). Transmission electron microscopy revealed that regions of Caco-2L cells were composed of multiple cell layers rather than the monolayers observed in Caco-2E cells. Epithelial cell height (or barrier thickness) was not significantly different between the two cell populations. Intercellular and intracellular lumina were observed in the Caco-2L cells, but not in the Caco-2E cells. Results of [3H]thymidine incorporation assays showed significantly higher cell proliferation rates in Caco-2L cells relative to Caco-2E cells. Despite morphological and physiological changes, there were no significant differences in the apparent permeabilities for D-mannitol (paracellular diffusion marker), hydrocortisone (transcellular diffusion marker), or dipeptide, Gly-Sar (carrier-mediated transcellular transport marker) between the two populations of cells. The higher TEER values in Caco-2L cells may be the results of a slight perturbation of tight junctions associated with both the multiple cell layers and the presence of intercellular lumina.

Pathogenesis of Human Enterovirulent Bacteria: Lessons from Cultured, Fully Differentiated Human Colon Cancer Cell Lines

“…The culture medium used also influences the growth and the functional differentiation of the cells. Indeed, some human colon cancer cells lines, subpopulation, and clones can form multilayers in culture in which only the top layer of cells are fully differentiated (243,247,248). This phenomenon has been observed particularly for parental Caco-2 cells when the fetal bovine serum used contains high levels of cyclic AMP (cAMP), and the result is that cell proliferation seems to be preponderant relative to cell differentiation (A. L. Servin, unpublished data).…”

“…It is therefore important to carry out regular checks of the polarized organization of the cells by indirect immunofluorescence labeling of SI coupled with a confocal laser scanning microscopy examination and determination of the activity of brush border-associated hydrolases (243,246). The passage number also influences the morphological and functional differentiation of the cells (243,(247)(248)(249). The culture medium used also influences the growth and the functional differentiation of the cells.…”

Methylated Flavonoids Have Greatly Improved Intestinal Absorption and Metabolic Stability

“…Apparent permeability coefficients (P app ) were calculated using the following equation (Artursson and Magnusson, 1990;Lu et al, 1996): P app ϭ (V/AC 0 ) ⅐ (dC/dt), where V is the volume of the solution in the basolateral chamber (1.8 ml), A is the membrane surface (1 cm 2 ), C 0 is the initial concentration in the apical chamber (5 or 10 M), and dC/dt is the change in flavone concentration in the basolateral solution over time.…”

Decay-Accelerating Factor Binding Determines the Entry Route of Echovirus 11 in Polarized Epithelial Cells

“…Results are expressed as apparent permeability coefficients (10,32,34,48) and displayed in Fig. 8B, and they show evidence of increases of diffusion of 1.5-and 3.0-fold for dextran (10 kDa) and mannitol, respectively, after infection with EV11-207, suggesting that the tight junctions became more permeable to these compounds.…”

“…Flux of [ ]dextran (5 Ci) were added to the apical compartment (t ϭ 0), and samples (medium; 10 l) were removed from the basolateral compartment after 1 h at 37°C. Radioactivity in each sample was counted, and the apparent permeability coefficient was calculated (10,32,48).…”