Painting mice

Why are we recording a video of my colleague Rita Santos painting the back of a white IKEA mouse with a black marker pen?

The background story is that nearly 50 years ago, in 1974, a US researcher painted real laboratory mice as part of what has become a well known story of scientific misconduct in biomedical research. The story isn’t as well-known among biologists and animal scientists as it is among immunologists (or at least so I assume, based on anecdotal evidence = whom among my contacts and colleagues who were or were not aware of it when I asked), despite being both striking and somewhat sad.

Striking, because once you’ve heard the story, you are likely to remember it. Dr William T Summerlin was doing research into transplantation immunology. He believed that by keeping the tissue in laboratory culture for some time before transplanting it into the recipient animal, it could be transplanted without rejection. His proof-of-concept experiment was to graft skin from black mice to (genetically unrelated) white mice. Did he actually ever transplant skin? I don’t know – this amount of detail is not given in the easily accessible internet sources. But what is very clear is that his demonstration of success was a fraud. An attentive technician discovered that the black patch on the back of the white mouse could be rubbed off with ethanol. As reported in this NY Times account of the case, published only a month later, Summerlin admitted to having painted the mice.

Sad, for a number of reasons, going beyond the actual misconduct itself, which is of course in itself highly lamentable. The painted mice seems not to be a one-off event – when Summerlin was investigated the committee also discovered a seemingly very dubious case of cornea transplant experiments in rabbits. Whereas having their backs painted would hardly have harmed the mice, the failed cornea transplants must have caused the rabbits pain. And none of this was justified. Scientific experimentation is not about simply trying something to see if it works: there has to be a reasonably developed idea of what mechanisms are involved. I don’t find any reference to a theory about mechanisms involved in the purported transformation of a xenograft (from a genetically different individual) into tissue that is not recognised as foreign when transplanted into a recipient. All that is to be found is that Summerlin had claimed for some years that he had a method for laboratory culture of tissues that removed the problem with transplant rejection, and that other researchers were unable to make the procedure work when they tried to repeat it in their own labs (a classic way through which fraudulent or poorly conducted research is discovered). The requirement that an experiment is based on a reasonably developed theoretical framework and previous, related studies is even stronger when the health and well-being of living beings are involved.

Why, then, are we painting mice? As part of the INTEGRITY project, we are developing teaching material into ethics and research integrity issues in animal experimentation, for high school students, ready for road testing in about a month. And please note, we’re not painting mice, we’re painting toy mice. The first R, Replacement, of the 3Rs principle of course. Knowing what mice are like, I actually believe that using real mice for this purpose would not only have been stressful for them but a pain for us!