Other stomach microbiota modulate resistance to H. pylori-driven ulcers

March 25, 2013

Mice with different naturally occurring stomach bacteria have distinct susceptibilities to disease caused by Helicobacter pylori, the well-known cause of ulcers in humans, according to a study published online ahead of print in the journal Infection and Immunity. This is the first study to document (in mice) that the presence of certain bacteria in the stomach microbiota can prevent pathology from H. pylori.

The gastro-intestinal tract is a veritable ecosystem packed with microbes, and over the last decade, investigators have been discovering that the species composition of that ecosystem can have a profound effect on human health. But the eureka moment that led to this study came "when we realized that mice from different vendors mount different responses to H. pylori infection," says principal investigator Karen Ottemann of the University of California, Santa Cruz.

Following this discovery, the researchers divided mice from the vendor, Taconic Farms, into three groups: mice treated with antibiotics in order to kill some of the resident bacteria, mice that were fed normal stomach bacteria after antibiotic treatment, and mice that were not treated. They then infected each group with H. pylori, and assayed the animals' stomachs for .

"The antibiotic-treated mice had small quantities of particular , called Th1 T helper cells," says Ottemann. Both the untreated mice, and the treated mice that were then fed normal had normal (higher) levels of Th1 T . These results suggested that the normal stomach microbes contribute to disease caused by H. pylori, says Ottemann.

The researchers then determined that around 4,000 were different in the high- and low-inflammation (no antibiotics, and antibiotic-treated, respectively) mice. Notably, the mice with low inflammation "had elevated amounts of Clostridia, bacteria known to prevent inflammation in the intestine," says Ottemann. Thus, the Clostridia may be key to dampening H. pylori pathology, although that remains to be determined, she says.

Ottemann says that this research may lead to predicting future H. pylori disease, including ulcers and gastric cancer—which has few treatment options and high mortality—based on stomach .

"After we determine which microbes underlie H. pylori disease outcomes, we could test whether H. pylori-infected people harbor those particular bacteria, and target them for curing," says Ottemann. Alternatively, such people could receive the protective bacteria as probiotics. The latter might be a superior option, because while prone to ulcers in middle and advanced age, people who harbor H. pylori are less likely to get esophageal cancer and asthma.

Explore further: Some bacteria may protect against disease caused by stomach infection

More information: A.S. Rolig, C. Cech, E. Ahler, J.E. Carter, and K.M. Ottemann, 2013. The degree of Helicobacter pylori inflammation is manipulated by the pre-infection host microbiota. Infect. Immun. Online ahead of print 19 February 2013, doi:10.1128/IAI.00044-13

Related Stories

Some bacteria may protect against disease caused by stomach infection

March 12, 2013
Half of the world's human population is infected with the stomach bacteria called Helicobacter pylori, yet it causes disease in only about 10 percent of those infected. Other bacteria living in the stomach may be a key factor ...

Ulcer-causing bacteria tamed by defect in cell-targeting ability

November 21, 2011
Without the ability to swim to their targets in the stomach, ulcer-causing bacteria do not cause the inflammation of the stomach lining that leads to ulcers and stomach cancer, according to a new study by researchers at the ...

Ulcer bacteria may contribute to development of Parkinson's disease

May 22, 2011
The stomach bacteria responsible for ulcers could also play a role in the development of Parkinson's disease according to research presented today at the 111th General Meeting of the American Society for Microbiology.

DNA from common stomach bacteria minimizes effects of colitis

May 5, 2011
DNA from Helicobacter pylori, a common stomach bacteria, minimizes the effects of colitis in mice, according to a new study by University of Michigan Medical School scientists.

Recommended for you

Genetic immune deficiency could hold key to severe childhood infections

July 18, 2017
A gene mutation making young children extremely vulnerable to common viruses may represent a new type of immunodeficiency, according to a University of Queensland researcher.

What are the best ways to diagnose and manage asthma?

July 18, 2017
What are the best ways to diagnose and manage asthma in adults? This can be tricky because asthma can stem from several causes and treatment often depends on what is triggering the asthma.

Large multi-ethnic study identifies many new genetic markers for lupus

July 17, 2017
Scientists from an international consortium have identified a large number of new genetic markers that predispose individuals to lupus.

Study finds molecular explanation for struggles of obese asthmatics

July 17, 2017
A large, bouquet-shaped molecule called surfactant protein A, or SP-A, may explain why obese asthma patients have harder-to-treat symptoms than their lean and overweight counterparts, according to a new study led by scientists ...

Team identifies potential cause for lupus

July 14, 2017
Leading rheumatologist and Feinstein Institute for Medical Research Professor Betty Diamond, MD, may have identified a protein as a cause for the adverse reaction of the immune system in patients suffering from lupus. A better ...

Immunosuppression underlies resistance to anti-angiogenic therapy

July 14, 2017
A Massachusetts General Hospital (MGH) research team has identified a novel mechanism behind resistance to angiogenesis inhibitors - drugs that fight cancer by suppressing the formation of new blood vessels. In their report ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.