Promotion of research on in vitro immunotoxicology.

ECVAM was established to play a leading role at the European level in the independent evaluation of the reliability and relevance of test methods and testing strategies for specific purposes through research on advanced methods and new test development and validation, so that chemicals and products of various kinds, including medicines, vaccines, medical devices, cosmetics, household products and agricultural products, can be manufactured, transported and used more economically and more safely, whilst the current relevance on animal test procedures is progressively reduced. Nowhere is this activity more necessary than in the field of immunotoxicology, where we know that chemicals and products of many kinds have the potential to stimulate, modulate or suppress the induction or expression of various types of immune responses. The problem is to effectively evaluate the potency of these effectors, and, since the available information is currently based on rather qualitative animal tests, to evaluate the true relevance of this knowledge and apply it intelligently in risk assessment processes which will protect human beings without unnecessarily limiting the development and use of materials which otherwise have economic, health and social benefits. The way forward must depend on the following: (a) a better understanding of immunotoxicological processes, based on a sounder understanding of the immune system itself (and of its network of control systems and interrelationships with other body systems); (b) The use of in vitro (not in vivo) systems based on human (not animal) cells and tissues; (c) integrated and tiered testing strategies, incorporating QSAR, as well as in vitro approaches; (d) taking advantage of the use of cells or factors from humans who have been exposed to potential immunotoxins, be this voluntarily, occupationally, environmentally or by accident; and (e) the recognition that virtually everything will effect one or more aspects of the immune system at some dose level and, in some circumstances, deciding when such effects are relevant, is the key to immunotoxicity testing. Some current ECVAM-sponsored work and activities at ECVAM are described.