Blood-brain barrier in vitro models and their application in toxicology. The report and recommendations of ECVAM Workshop 49.

This is the report of the forty-ninth of a series of workshops organised by the European Centre for the Validation of Alternative Methods (ECVAM). ECVAM’s main goal, as defined in 1993 by its Scientific Advisory Committee, is to promote the scientific and regulatory acceptance of alternative methods which are of importance to the biosciences and which reduce, refine or replace the use of laboratory animals. One of the first priorities set by ECVAM was the implementation of procedures which would enable it to become well-informed about the state-of-the-art of non-animal test development and validation, and the potential for the possible incorporation of alternative tests into regulatory procedures. It was decided that this would be best achieved by the organisation of ECVAM workshops on specific topics, at which small groups of invited experts would review the current status of in vitro tests and their potential uses, and make recommendations about the best ways forward (1). This ECVAM workshop on in vitro models for studying the blood–brain barrier (BBB) and their application in toxicology was held at ECVAM on 19–21 May 2003. The workshop was chaired by Bas Blaauboer and was attended by pharmacologists and toxicologists from academia and industry, including experts on the BBB and in neurotoxicology. The current status of in vitro models of the BBB was discussed, focusing on their application in toxicology in general and, in particular, in regulatory toxicology in the context of the European Union (EU) chemicals policy (2) and the Seventh Amendment to the Cosmetics Directive (3). An important aspect of the workshop was consideration of the inclusion of biokinetic modelling, the BBB and target organ toxicity in integrated testing strategies.