Fresh insight on Crohn’s disease


Scientists are still looking for the cause of Crohn’s disease, but it looks like they are getting closer. As of now, it is believed that Crohn’s stems from the combination of certain genes along with an immune reaction, but there was not much more detail on either the genes or the reason for the abnormal immune reaction.

Until now.

Catherine Leimkuhler Grimes, assistant professor of chemistry and biochemistry at the University of Delaware, and Vishnu Mohanan, doctoral student in biological sciences from the same university, recently published a paper in the Journal of Biological Chemistry about some new discoveries that may change the way Crohn’s is treated. They have found that one of the genetic factors involved is related to a “bodyguard protein”, which in turn strengthens another protein known to be related to Crohn’s disease.


What’s a bodyguard protein? Let’s start at the gut: we need help from millions of good bacteria to break down our food into nutrients that can seep into the blood flow. On the other hand, our immune system has to be on the lookout for harmful microbes in order to defend us from them. So what does the body do? It deploys a host of specialized proteins that identify and “mark” bacteria so the body knows whether it should be eliminated or hosted. If all goes well, you have a healthy gut – but bacteria often malfunction or mutate, which might lead to pathogens flourishing, or healthy and necessary bacteria being attacked. Scientists suspect that inflammatory diseases of the gut (such as Crohn’s) stem from such immunological failures.

Now for the breakthrough: Professor Grimes and Mr. Mohanan were investigating a protein called NOD2, which frequently mutates and has been often linked to Crohn’s disease, and they discovered another protein, called HSP70, short for Heat Shock Protein 70. HSP70 is a chaperone or bodyguard protein, and the big discovery was that if there is HSP70 then the faulty versions of NOD2 start working correctly. Professor Grimes explained: "Basically, HSP70 keeps the protein around - it kind of watches over and protects NOD2, and keeps it from going in the cellular trash can."

The studies have only been carried out in human cell lines so far, but the researchers are now trying to gain access to human tissue (in collaboration with Nemours/A.I. duPont Hospital for Children) to find out how increasing HSP70 affects the levels of NOD2, and hopefully start laying the groundwork of a treatment or cure.

According to the Crohn's and Colitis Foundation of America there are around 700,000 people with Crohn’s in the USA alone.