Nature first revealed that T cells signal to the immune system to stop attacking cells in the intestinal mucosa

A new study may have solved a mystery

Past studies have found that there is some sort of genetic change (mutation) in most patients with the disease, from which a clue emerges

The new study, conducted in mice and human tissues, published online on Oct.

The study, led by researchers at New York University's Grossman School of Medicine, supports the theory that API5 protects most people with mutations from disease until a second trigger, such as norovirus infection, pushes some people past the disease threshold

In experiments centered on transgenic mice with mutations associated with human Crohn's disease, mice injected with API5 survived, while half of the mice that were not injected died

"Our findings provide new insights into the critical role of apoptotic inhibitor 5 in Crohn's disease," said

Matsuzawa-Ishimoto, a postdoctoral researcher at the Langany Health Center at New York University, points out that current treatments work by suppressing the immune system, putting patients at high risk of infection and often with poor results after several years of use

In another set of experiments, the researchers created organ-like structures

"Our findings help explain why the genetic link to Crohn's disease is much broader than the actual number of people with the disease," said

"Our study shows that when norovirus infects people with a weakened ability to produce apoptotic inhibitor 5, it causes a full-blown autoimmune disease

Cadwell cautioned that while the study's authors extracted the API5 protein from human tissue rather than rodents, it's unclear whether this injection therapy can be safely applied to humans

The next step for the research team is to explore the long-term effects of API5 injections to better understand whether prospective treatments can effectively control Crohn's disease, which can recur over a long period of