Same Gut Bacteria Can Trigger Varying Immune Responses

A team of researchers from an array of academic institutions in the United States teamed up to perform a study on gut bacteria and immune responses.  They determined a certain type of gut bacteria stimulates varying immune responses. The type of immune response triggered by the bacteria hinges on the state of the environment. The study's details and results were recently outlined in a paper published in Science Immunology.

Gut Bacteria

Human beings have countless types of gut bacteria in their bodies. The vast majority of these gut bacteria types are helpful. They perform functions like helping the body digest specific foods. However, other types of bacteria can find their way into the gut and spur problems like colitis, ulcer, and cancer.

About the Study

The research team studied Helicobacter in-depth. This is a bacteria genus that is believed to be a possible contributor to the creation of ulcers as well as other health issues in the gut. The researchers studied what happened to mice when bacteria was placed in their guts. The researchers varied the conditions to gain a more in-depth understanding of how the introduction of bacteria affected the mice when certain conditions were changed.

Results

The researchers determined that introducing the bacteria into the guts of healthy mice that were raised in as germ-free of an environment as possible created an immune response typically linked to tolerance. Previous research suggested this response is the body's means of signaling the acceptance of bacteria in the gut as it doesn't pose a threat.

When the same style of bacteria was placed in the gut of a mouse where colitis exists, it caused an immune threat response. This occurred as the bacteria caused already-existing inflammation of the gut to worsen. It is clear the immune system considered the bacteria to be a harmful presence that must be halted. 

Why the Results Matter

The findings matter as they suggest at least one type of bacteria might be seen as harmful or harmless based on the state of environment it is placed in. This suggests the same phenomenon might occur with other types of bacteria. The finding has the potential to lead to an improved understanding of the role bacteria play in the body's gut biome as well as its health. The hope is that medical researchers will eventually use these findings to develop better treatments for those who are plagued by stomach maladies.