ATLA::Alternatives to Laboratory Animals

Volume 30, Number 1

Follow-up to the ECVAM prevalidation study on in vitro tests for acute skin irritation

ValÉRie Zuang,¹ Michael Balls,¹ Philip A. Botham,² Alain Coquette,³ Emanuela Corsini,⁴ Rodger D. Curren,⁵ Graham R. Elliott,⁶ Julia H. Fentem,⁷ Jon R. Heylings,² Manfred Liebsch,⁸ JesÚS Medina,⁹ Roland Roguet,¹⁰ Johannes J.M. Van De Sandt,¹¹ Christianne Wiemann¹² And Andrew P. Worth¹

¹ECVAM, Institute for Health & Consumer Protection, European Commission Joint Research Centre, 21020 Ispra (VA), Italy; ²Syngenta, Central Toxicology Laboratory, Alderley Park, Macclesfield, Cheshire SKIO 4TJ, UK; ³SGS BioPharma, Department of Biology, 10 Vieux Chemin du Poéte, 1301 Wavre, Belgium; ⁴Laboratory of Toxicology, Department of Pharmacological Sciences, Via Balzaretti 9, 20133 Milan, Italy; ⁵1nstitute for In Vitro Sciences, Inc., Suite 220, 21 Firstfield Road, Gaithersburg, MD 20878, USA; ⁶Department of Pharmacology, TNO-PML, 2280 AA Rijswijk, The Netherlands; ⁷SEAC Toxicology Unit, Unilever Research, Colworth House, Sharnbrook, Bedfordshire MK44 1LQ UK; ⁸ZEBET, BgVV, Diedersdorfer Weg 1, 12277 Berlin, Germany; ⁹1nstituto de Salud Carlos III, Escuela Nacional de Medicina del Trabajo, Pabillon 8, Ciudad Universitaria, 28040 Madrid, Spain; ^1OL'Oréal Life Sciences Research, Centre C. Zviak, 90 rue du Général Roguet, 92583 Clichy Cedex, France; ¹¹TNO Nutrition & Food Research, Department of Explanatory Toxicology, Utrechtseweg 48, 3700 AJ Zeist, The Netherlands; ¹²BASF AG, 67056 Ludwigshafen, Germany

SUMMARY

The European Centre for the Validation of Alternative Methods (ECVAM) Skin Irritation Task Force was established in 1996, to review the status of the development and validation of alternative tests for skin irritation and corrosion, and to identify appropriate non-animal tests for predicting human skin irritation that were sufficiently well-developed to be prevalidated and validated by ECVAM. The EpiDerm™ method, based on a reconstituted human skin model, was proposed as being sufficiently well advanced to enter a prevalidation (PV) study. Based on a review of test protocols, prediction models (PMs), and data submitted by test developers on ten specified chemicals, with 20% sodium lauryl sulphate as a reference standard, the task force recommended the inclusion of four other tests: EPISKIN™ and PREDISKIN™, based on reconstituted human epidermis or on human skin; the nonperfused pig-ear test, based on pig skin; and the skin integrity function test (SIFT), with ex vivo mouse skin. The prevalidation study on these methods was funded by ECVAM, and took place during 1999-2000. The outcome of the PV study was that none of the methods was ready to enter a formal validation study, and that the protocols and PMs of the methods had to be improved in order to increase their predictive abilities. Improved protocols and PMs for the EpiDerm and EPISKIN methods, the pig ear test, and the SIFT were presented at an extended Task Force meeting held in May 2001. It was agreed that, in the short term, the performance of the revised and harmonised EpiDerm and EPISKIN methods, as well as the modified SIFT, should be evaluated in a further study with a new set of 20 test chemicals. In addition, it was decided that the SIFT and the pig-ear test would be compared to see if common endpoints (transepidermal water loss, methyl green-pyronine stain) could be identified.

Keywords: skin irritation, prevalidation, validation, EpiDerm, EPISKIN, pig-ear test, skin integrity function test, in vitro, alternative methods