title: A modified fast (4 day) 96-well plate Caco-2 permeability assay.
abstract: BACKGROUND
  The Caco-2 permeability assay is widely used for lead optimization in drug discovery. A 3 to 5-day system using a 24-well plate and a 10 to 21-day system using a 96-well plate have been established. Here, we modified the assay system to provide a ready-to-use Caco-2 cell monolayer using a 96-well plate in just 4 days.
  
  
  RESULTS
  In our system, collagen-coated inserts and the prolongation of the culture period after seeding leads to greater Caco-2 cell proliferation and sufficient contact-inhibition. The differentiation of Caco-2 cells was enhanced, when the contact-inhibited Caco-2 cells were exposed to the differentiation-inducing agent butyric acid. The permeability to nine well-known compounds showed a statistical correlation between our 4-day system using a 96-well plate and the conventional 21-day system using a 24-well plate.
  
  
  CONCLUSIONS
  We conclude that our system is more useful for evaluating many compounds for lead optimization in drug discovery.
authors.affiliation: Toxicology and Pharmacokinetics Laboratories, Pharmaceutical Research Laboratories, Toray Industries, Inc, Kamakura, Kanagawa, Japan. Masashi_Uchida@nts.toray.co.jp
authors.forename: Masashi
authors.initials: M
authors.lastname: Uchida
authors.forename: Tominaga
authors.initials: T
authors.lastname: Fukazawa
authors.forename: Yuri
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hashimoto
authors.forename: Yohei
authors.initials: Y
authors.lastname: Miyamoto
mesh_terms: D020148:Butyric Acid / Q000494:pharmacology; D018938:Caco-2 Cells; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D002986:Clinical Trials as Topic; D020099:Coated Materials, Biocompatible; D055808:Drug Discovery / Q000379:methods*; D006801:Humans; D004364:Pharmaceutical Preparations / Q000737:chemistry / Q000145:classification / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D013997:Time Factors; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D020099:Coated Materials, Biocompatible; D004364:Pharmaceutical Preparations; D020148:Butyric Acid; D014747:Vinblastine; D011433:Propranolol