Abstract
The murine local lymph node assay (LLNA) is a widely accepted alternative test to assess the skin sensitizing potential of chemical substances. The original LLNA was designed to quantify lymph cell proliferation in the draining auricular lymph nodes by incorporation of radiolabeled thymidine analogues. To avoid use of the radioisotope in the tests, some modified LLNA protocols were developed. One of the modified methods utilizes the nucleus (uridine) analogue of 5-Bromo-2'-deoxiuridine (BrdU). In this method, the incorporated BrdU is measured by ELISA, using anti BrdU antibody. This modified LLNA:BrdU-ELISA has been validated and adopted as OECD test guideline 442B. In this guideline, the CBA/J or CBA JN strains are recommended, since researchers had used these strains during the validation. Previously, we noted differences in response in the LLNA with different strains of mouse. . In this study, we used mice of several CBA strains to compare the reactivity against several skin sensitizers and a non sensitizer. It is confirmed that the mouse strains, CBA/CaOlaHsd and CBA/NSlc showed similar but not equal response to CBA/JNCrlj, the preferred strain in the LLNA:BrdU-ELISA.
