Ryan, C., F. Gerberick, L. Cruse, D. Basketter, L, Lea, L. Blaikie, R. Dearman, V. Warbrick, and I. Kimber. Activity of Human Contact Allergens in the Murine Local Lymph Node Assay. ATLA 1999. 27: 115.

The murine local lymph node assay (LLNA) is a predictive test method for identification of chemicals that have the potential to cause skin sensitisation. Since its original development, the assay has been the subject of national and international evaluation studies and extensive comparisons with guinea-pig tests and human data. On the basis of these investigations, the LLNA has recently been endorsed by the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) as a stand-alone method for skin sensitisation testing. At the same time ICCVAM confirmed that, although the LLNA is not an in vitro method, it does permit a reduction in, and a refinement of, the use of animals in sensitisation hazard assessment. The investigations described here were designed to further explore the ability of the LLNA to accurately identify those chemicals that cause allergic contact dermatitis in humans. To that end, we have measured, in three laboratories, LLNA responses induced by 18 test chemicals, 12 of which are known to cause skin sensitisation and 6 of which are believed not to be associated with allergic contact dermatitis. The results of these investigations provide additional evidence that the LLNA is able to discriminate between skin sensitisers and non-sensitisers, and provides a method for hazard identification that offers important animal welfare benefits.