Caco-2 Cell Line

The human epithelial cell line Caco-2 has been widely used as a model of the intestinal epithelial barrier. The Caco-2 cell line is originally derived from a colon carcinoma. However, one of its most advantageous properties is its ability to spontaneously differentiate into a monolayer of cells with many properties typical of absorptive enterocytes with brush border layer as found in the small intestine. The Caco-2 cell line is heterogeneous and contains cells with slightly different properties. Thus, cultivation conditions can be expected to select for the growth of subpopulations of cells resulting in a cellular model system with properties that may differ from the original cell line. Accordingly, results obtained under similar experimental conditions in different laboratories may not be directly comparable. Due to this, a variety of cloned Caco-2 cell lines has been established, and described in the literature. This chapter will however, focus on describing how to handle and cultivate the original Caco-2 cell line as obtained from cell culture collections like American Type Culture Collection and the European Collection of Cell Cultures. Detailed protocols for handling the Caco-2 cells in the laboratory are provided. Furthermore, in Chap. 9 general protocols for measuring barrier function by transepithelial resistance (TEER), and monolayer integrity by Lucifer Yellow flux are described. Proper testing of the cell monolayer is absolutely critical in exploiting Caco-2 cells to measure interaction, uptake and cellular transport of drugs and food components.