Transport properties are not altered across Caco-2 cells with heightened TEER despite underlying physiological and ultrastructural changes.
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.
Lu
S
S
Department of Pharmacokinetics/Drug Metabolism, Parke-Davis Research Division, Warner-Lambert Company, Ann Arbor, MI 48105, USA.
Gough
A W
AW
Bobrowski
W F
WF
Stewart
B H
BH
D018938:Caco-2 Cells / Q000502:physiology* / Q000648:ultrastructure*; D002478:Cells, Cultured; D017097:Electric Impedance; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D008854:Microscopy, Electron; D013936:Thymidine / Q000494:pharmacology; D013997:Time Factors
D013936:Thymidine; D006854:Hydrocortisone