a photograh of a brown mouse

Photograph by George Shuklin

Normally when we do posts on scientific studies concerning celiac disease and gluten intolerance, we have to put in a lot of “maybe”s and “could”s and “however”s into the post. But a new study, published in the latest edition of the journal Nature, can be approached with a little less caution. I would even argue that it’s one of the most promising studies we’ve seen in a long time. Plus, the study was done with a control group of mice, which meant I got to spend half an hour looking at adorable pictures of mice on the internet, so that was a bonus.

Since I’d hate to leave you in suspense, I’m going to jump ahead to the implications of the study before going into all the polysyllabic details: a huge step has been made toward developing a treatment that could not only manage symptoms of severe celiac disease, but could potentially prevent the development of the disease in high-risk individuals.

Excited yet?

Now let’s start from the beginning.

So, humans have an inflammatory protein called interleukin-15, or IL-15 for short. IL-15’s job is largely to regulate T-cells, and has been shown to increase the anti-tumor immunity of some specific kinds of T-cells, which is good. What’s not so good is that an excess of IL-15 has already been implicated in multiple inflammatory diseases such as rheumatoid arthritis. We’ve known about IL-15’s dark side for awhile now, and medications that block IL-15 are currently being developed to treat conditions like RA.

You can probably see where this is heading. Since celiac disease is an inflammatory disease as well, a team set out to see if blocking IL-15 could be effective in treating celiac disease (click the link for Web MD’s write-up of the study). They first genetically altered a group of mice to give them celiac disease (anyone up for an animal rights debate?), and then treated the mice by blocking their IL-15. The results? The disease’s symptoms were reversed, and the mice were once again able to eat gluten with no detrimental side effects (“That’s great and all, but I prefer cheese anyway.” -The mice).

Gerald Mullin, MD, an associate professor of medicine at Johns Hopkins, says the study holds promise. “IL-15 may be a major player in driving the inflammatory response in celiac disease, and if we block it, you can tolerate gluten,” says Mullin. “A drug that blocks IL-15 may be most beneficial in people with really aggressive disease that doesn’t respond to conventional dietary measures,” he adds.

Most beneficial to people suffering the most? I’m sold. But hold your applause for a second while we hear the requisite “However….”

This one comes courtesy of Richard Desi, MD, a gastroenterologist at the Melissa L. Posner Institute for Digestive Health and Liver Disease at Mercy Medical Center in Baltimore. “This may not be it for everybody,” he says, “but maybe it can help some people. We are starting to understand celiac disease a lot more and diagnose it a lot more. The hope is that we will be able to come up with a treatment that doesn’t just involve a gluten-free diet.”

As “however”s go, that one is pretty optimistic. One of the most interesting implications of the study is that a treatment that blocks IL-15 could not only be effective in treating celiac disease, but in preventing it in high-risk folks as well (people with family histories of celiac, for example). The article didn’t mention if there were any potentially negative effects of blocking IL-15, which I’m taking to mean that the risks aren’t high enough to mention (feel free to burst my bubble, though). While blocking IL-15 might not do much for someone with a gluten allergy or a gluten intolerance, the potential here is astounding.

An interesting side-note: the study also found that retinoic acid, a vitamin-A derivative found in acne treatments such as Retin-A and Accutane, may be another culprit in celiac disease. That’s because retinoic acid acts as IL-15’s little sidekick, fueling the production of the protein and further exacerbating celiac symptoms. One scientist actually says that vitamin A may not be a great idea for celiac patients, and that even topical ointments containing retinoic acid can potentially enter the bloodstream and cause problems. Any celiacs who use such products may want to bring this issue with up with an understanding physician, gastro, or holistic doctor if you’re concerned.

So what do we think? Excited? Super excited? Annoyed that IL-15 blocking won’t treat your gluten intolerance? Have a 10-page treatise on rights for laboratory animals? Have at it in the comments!

Edit:A couple of very helpful commenters pointed out that there was a preceding study, published in the Proceedings of the National Academy of Science, that found that blocking IL-15 led to a reversal of intestinal damage in mice. The study was conducted at the Tokoyo Metropolitan Instititue of Medical Science by a Yokoyama S, Watanabe N, Sato N, Perera PY, Filkoski L, Tanaka T, Miyasaka M, Waldmann TA, Hiroi T, Perera LP. The full study is available here. The study in Nature was about the role of Vitamin A in the function of IL-15. Sorry for any confusion!

Someone else also commented that I neglected to credit the research team for the Nature study. That one took place at the University of Chicago, and the team was led by Dr. Bana Jahbri. Again, I’m sorry for not giving you guys the full picture, and thanks to all the readers who helped me out!