The 2010 laboratory animal use statistics for Great Britain revealed that just over 3.7 million scientific procedures using animals were commenced, representing an increase of 3% (105,000) over the previous year. Laboratory animal numbers have steadily risen across the preceding decade, largely due to increasing use of genetically altered animals. However, their use has disturbing implications for animal welfare. Similar concerns are raised by increasing use of non-human primates, and of procedures conducted without any form of anaesthesia.
Approximately 4,000 – 5,000 scientific procedures using non-human primates (NHPs) are commenced annually in Great Britain. The 2011 review by Bateson and colleagues was the first major systematic assessment of the ethics of this research. It concluded that 91% of 67 NHP studies conducted from 1997 – 2006 were ethically justifiable. However, the review systematically underestimated the costs to the NHPs. Additionally, it concluded that the medical impacts of a significant proportion of studies was low, and was sometimes exaggerated. Accordingly, the majority of these studies were incorrectly assessed as ethically justified. Many of the responses of the funding organisations to the review's recommendations were positive. Deeply concerning, however, was their failure to adequately acknowledge or respond to repeated criticisms concerning unsubstantiated claims and exaggerations of the medical value of NHP research. Clearly, poorly-substantiated claims about the medical utility of NHP studies by researchers or their funding organisations must be met with considerable caution.
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.