In a healthy gut, the immune system knows the difference between the trillions of good bacteria and the bad. A properly functioning immune system identifies the bad intruders that can do us harm and reacts appropriately to neutralize threats and maintain health.

However, in the gut of a patient with an inflammatory bowel disease (IBD), the immune system makes mistakes, misidentifying the good versus bad. This leads to inflammation and ulceration of the digestive tract and various symptoms associated with Crohn’s disease and ulcerative colitis.

Autoimmune issues

There is not simply one Crohn’s disease, or one ulcerative colitis. Within each patient, there are a near infinite number of variables that can influence how the immune system responds to pathogens or to any of the trillions of bacteria, fungi and viruses that normally live in the gut (known as the gut microbiome).

“Within each patient, there are a near infinite number of variables that can influence how the immune system responds to pathogens...”

In patients with IBD, there are several factors in particular that may play a role in how the immune system responds. For example, an abnormal immune response occurs in people who have inherited genes that make them susceptible to IBD. Unidentified environmental factors serve as the trigger that initiates the harmful immune response in the intestines, and the microbiome clearly plays an important role.

Alleviating discomfort

There is a wide array of available treatments that have helped many IBD patients achieve remission. Some disease modifying treatments are designed to dampen an overly aggressive immune response, whereas others are designed to give the immune system a boost.

Research is being conducted to better understand IBD, its triggers and the immune responses within both the healthy and unhealthy gut. This research is being integrated with existing IBD research about genetics, the microbiome and the environment. One day, a blood or stool sample or intestinal biopsy from a patient may allow us to quickly see what’s happening to his or her gut immune response, and to understand the specific causes. This will allow us to select personalized therapies, or develop new ones, that address what’s happening in each individual and help even more patients find remission.