Prediction of intestinal drug absorption and drug-induced intestinal toxicity is critical for the development of orally-administered drugs. However, it is difficult to accurately predict these events because of large species differences and a lack of appropriate in vitro assay. Then, we proposed the use of human crypt-derived intestinal cells for the prediction of intestinal absorption and the risk of intestinal toxicity. 3D human intestinal spheroids were established from fresh surgical specimens of proximal jejunum and terminal ileum using the conditioned media containing Wnt3a, R-spondin 3, and noggin. To generate 2D monolayer, spheroids were enzymatically dissociated into single cells and plated onto Matrigel-precoated culture plates/inserts. We have confirmed the activities of typical drug-metabolizing enzymes and uptake/efflux transporters in human jejunal spheroid-derived differentiated cells. Intestinal availability (Fg) estimated from the apical-to-basal permeation clearance across the jejunal monolayer showed a good correlation with in vivo human Fg values for five CYP3A substrate drugs. As for the prediction of intestinal toxicity, we found that the degree of ATP decreases in intestinal spheroids incubated with different EGFR-TKIs varied greatly depending on the drugs and the rank order of the extent of ATP decrease corresponded with that of frequency of clinically-observed diarrhea. We also constructed enterochromaffin (EC) cell-rich spheroids and quantified serotonin release from EC cells upon exposure to drugs for the prediction of drug-induced nausea and vomiting. As a result, we found that the serotonin release was related to the high/low risk of nausea and vomiting of each ALK/ROS1 kinase inhibitors.
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