As I discussed in a previous post, the call for a reliance on sound evidence in veterinary medicine resonates less strongly that we might hope because of the paucity of such evidence. Financial resources are the main limiting factor in obtaining good-quality basic and clinical research evidence, but apparently the attitude or culture of the profession may be a factor as well. According to a recent news story from the Veterinary Information Network (VIN), a widely used information and social resource for veterinarians, Dr. Richard Vulliet, a researcher and professor at the UC Davise School of Veterinary medicine has accepted a $100,000 grant from the AKC to study the use of bone marrow stem cells in degenerative myelopathy, a mysterious and all too common disease in which older dogs gradually lose the function in their hind legs.
Dr. Vulliet is clearly a trained, experienced researcher who should understand the importance of properly designed and conducted trials. Unfortunately, if the comments and attitude attributed to him in this article are correct, his frustration with the pace and limitations of proper research have led him to use the resources he has to “try out” some ideas without the structure or controls that make the results meaningful or useful to the rest of the profession.
According to the article, “Vulliet has treated four dogs with degenerative myelopathy with their own stem cells…Vulliet derives the mesenchymal stromal cells from bone marrow. He injects the cells systemically into the circulation because it appears that they home to an area of injury.”
The idea for the project apparently came from some laboratory rat research. “Vulliet says he got interested in treating these conditions because he was working with mesenchymal stem cells and their interaction with connective tissue, and it was boring. Then he came across two papers. In one of the papers, Japanese researchers described treating induced cardiomyopathy in experimental rats (Circulation 2005;112:1128-35)…Vulliet has not treated any dogs with dilated cardiomyopathy. But he has been in contact with Doberman groups to recruit possible subjects…In the other paper, researchers at Tulane University in New Orleans induced spine injuries in experimental rats and treated them with mesenchymal stem cells.”
Clearly, Dr. Vuillet recognizes some of the limitations of a research project based on limited information about plausibility and mechanism, “When I talk to possible clients, I generally get the impression they think I know what I am doing. But no, this is research.” Unfortunately, the limitations don’t seem to bother him as much as those of properly conducted scientific research, which he has chosen not to pursue because “the protocols he would be forced to adhere to at the university, working with pet dogs, would be too cumbersome.”
The article goes on to describe the haphazard followup of subjects, including one dog whose owner, apparently a neighbor of Dr. Vuillet, almost forgot to mention that she believed the dog had improved after treatment. The issue of potential hazards also arises, when the article mentions that 1 of the 4 dogs treated so far eventually developed a “malignant tumor on its spleen.” Clearly, splenic tumors are quite common in elderly dogs of the breeds Dr. Vuillet is studying, but any association, causal or chance, between the treatment and such disease is unlikely to be detected by casual, unsystematic followup.
What Dr. Vuillet seems to be doing is selecting a few owner with dogs who appear to have degenerative myelopathy (though how that is confirmed is unclear from the article) and who appear to have sufficiently low expectations for benefit from the procedure, and then giving them some stems cells and asking the owner someday how things are going. The value of data collected this way is so low that it is hard to justify spending $100,000 of the scarce funds available for veterinary research on it. Even more disturbing, from someone who clearly ought to know better, are statements suggesting this independant, idiosyncratic, approach to research is somehow superior to proper clinical studies; “ I think we will learn more from these dogs than from the thousands of Ph.D.s who are experimenting in the labs.”
If this is the attitude towards science that professors at our veterinary schools are teaching to their students, I fear that better studies and better data will not be more available in the future. And while I am only speculating, I will be very interested to see if Dr. Vuillet eventually introduces some version of stem cell therapy to the veterinary market as an entrepreneurial inventor in the coming years. Such a therapy would be more than welcome, and I would be eager to provide it to my clients, if the proper evidence for its safety and efficacy were available. I am doubtful, however, that such evidence will come from projects such as this one.