title: The role of in vitro methods as alternatives to animals in toxicity testing.
abstract: BACKGROUND
  It is accepted that animal testing should be reduced, refined or replaced as far as it is practicably possible. There are also a wide variety of in vitro models, which are used as screening studies and mechanistic investigations. The ability of an in vitro assay to be reliable, biomedically, is essential in pharmaceutical development. Furthermore, it is necessary that cells used in in vitro testing mimic the phenotype of cells within the human target tissue.
  
  
  METHODS
  The focus of this review article is to identify the key points of in vitro assays. In doing so, the authors take into account the chemical agents that are assessed and the integrated in vitro testing strategies.
  
  
  CONCLUSIONS
  There is a transfer of toxicological data from primary in vivo animal studies to in vitro assays. The key element for designing an integrated in vitro testing strategy is summarized as follows: exposure modeling of chemical agents for in vitro testing; data gathering, sharing and read-across for testing a class of chemical; a battery of tests to assemble a broad spectrum of data on different mechanisms of action to predict toxic effects; and applicability of the test and the integrated in vitro testing strategies and flexibility to adjust the integrated in vitro testing strategies to test substance. While these methods will be invaluable if effective, more studies must be done to ensure reliability and suitability of these tests for humans.
authors.affiliation: Universidad Complutense de Madrid, Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine , 28040-Madrid , Spain +34 91 394 38 34 ; +34 91 394 38 40 ; anadon@vet.ucm.es.
authors.forename: Arturo
authors.initials: A
authors.lastname: Anadón
authors.forename: María Aranzazu
authors.initials: MA
authors.lastname: Martínez
authors.forename: Victor
authors.initials: V
authors.lastname: Castellano
authors.forename: María Rosa
authors.initials: MR
authors.lastname: Martínez-Larrañaga
mesh_terms: D000826:Animal Testing Alternatives / Q000379:methods*; D000818:Animals; D002460:Cell Line; D006801:Humans; D015203:Reproducibility of Results; D018570:Risk Assessment; D018675:Toxicity Tests / Q000379:methods*