Cultured epithelial cells, transcellular

Transcellular Transport of Protein—Polymer Conjugates in Cultured Epithelial Cells... 

Current technologies provide for availability of cell culture models from a selection of the significant tissue barriers as either primary cell culture systems or continuous cell line cultures. A number of endothelial and epithelial cell systems can now be grown onto permeable supports as monolayer systems to facilitate transcellular transport. These cell culture models provide powerful tools for the pharmaceutical chemist to characterize fundamental cellular transport mechanisms at the biochemical and molecular levels and effective screening systems to facilitate appropriate drug design and development. Moreover, they all have applications in... 

For the evaluation of a possible relationship between the molecular structure of a potential candidate and its transport abilities to cross the epithelial membrane of the gut, the mechanism or route of transport must be known [1,4]. This is due to the structural requirements for the transcellular route being different from the paracellular route. During the lead optimization phase - when many mechanistically based studies are performed - the cell culture-based models can also be used with great confidence. 

The paracellular route is probably less significant in the transport of nanospheres as compared to the transcellular route Tlie tight junctions in between the cells may not allow nanospheres to cross the intestinal epithelial barrier via paracellular route. The transcellular route could allow a restricted passage of the nanospheres across the intestinal mucosal layer because of their moderate size range. In a tissue culture model using Caco-2 (enterocytes) cell monolayers, we have demonstrated transport of PLGA nanospheres across the cells. 

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