In Vitro Permeability Assays

Caco-2 cells have been extensively used over the last thirty years to study drug absorption across the human intestinal mucosa. The cells are seeded at a very specific cell number and differentiated for 21-days on transwell plates containing a permeable membrane support which results in apical and basal compartments, which artificially simulate the intestinal absorption into the bloodstream.

Caco-2 cells are considered an in vitro gold standard  for assessing oral drug absorption. This model provides reliable predictive permeability data either by passive diffusion and/or active transport for hydrophilic to moderately lipophilic compounds and can easily be adapted for high-throughput screening purposes.

The Caco-2 model is also useful to assay active transport of drugs in the central nervous system (CNS) since it expresses two efflux transporters that play a relevant role in the permeation of compounds across the blood brain barrier (BBB).

As a result of the combination of cells with an absorptive and mucus-secreting phenotype, this model possesses a mucus that differentiates it from the Caco-2 cell model. The cell barrier of this co-culture, moreover, is not as tight as that formed by Caco-2 alone and has TEER values more similar to those of the human small intestine. The tight junctions of Caco-2 cells, in contrast, more closely resemble the electrical resistance of the colon.

CacoGoblet is also considered a relevant cellular model for studies of drug absorption across the gastrointestinal barrier, either by passive diffusion and/or by active transport. The model can be easily adapted for high-throughput screening purposes. In addition to drug permeability testing CacoGoblet respond well to inflammatory mediators, providing valuable information on the efficacy of anti-inflammatory drugs.