Navigation Links
With sinus study, Saint Louis University researchers find that harmless members of microbiome spark immune reaction
Date:12/19/2013

ST. LOUIS Saint Louis University researchers have analyzed the microbiomes of people with chronic rhinosinusitis and healthy volunteers and found evidence that some chronic sinus issues may be the result of inflammation triggered by an immune response to otherwise harmless microorganisms in the sinus membranes.

The findings, recently published in JAMA Otolaryngology - Head & Neck Surgery, support mounting evidence that inflammation may be the cause of most chronic rhinosinusitis (CRS) instead of bacterial infection.

Study author Rajeev Aurora, Ph.D., professor of molecular microbiology and immunology at Saint Louis University, says that the paper sheds new light on the spectra of microorganisms that live in our bodies and our own immune response to those organisms.

Chronic rhinosinusitis, the inflammation of the sinus and nasal passages lasting more than three months, is one of the most common chronic conditions in the U.S.

The condition can be challenging for doctors to treat because the underlying mechanisms causing the condition are not well understood. While antibiotics can help some patients, others are not helped by drugs or more invasive treatments, such as surgery to open up sinuses. Doctors have proposed any number of causes, included allergy, immune deficiency, cystic fibrosis, gastroesophageal reflux, and structural abnormalities, but questions remain about the origin of the condition.

As scientists are learning more about the body's microbiome, the specific colonies of microorganisms like bacteria that live in various places in the body, including the mouth, the intestinal tract, and skin, they are becoming aware that the clusters of microbiota can be remarkably different from each other from place to place in the same person, as well as from the microbiota of other people.

Aurora and his research team decided to study the microorganisms that live in the sinus membrane to learn more about their role in CRS. Their initial hypothesis was a simple one: using newly available sequencing techniques, they would compare the bacteria and other microbiota in the sinuses of healthy people and those with CRS, and, if they could pinpoint specific bacteria in those with CRS, they would have their culprit.

In order to access the sinus membrane, Aurora collaborated with assistant professor of otolaryngology at SLU Thomas Sanford, M.D. to collect samples from patients who were undergoing surgery. Thirty patients had chronic rhinosinusitus and 12 were healthy controls, undergoing surgery for other reasons.

Once the samples were gathered, researchers examined two particular microbe genes bacterial 16S and fungal 18S ribosomal RNA genes and analyzed them with deep sequencing techniques.

"It turned out that the CRS and control groups were very similar, and the differences were not of the type that that would cause disease," Aurora said. "It did not appear that a particular microorganism was acting as a pathogen."

"So, we turned to look at the immune system."

And, indeed, Aurora and his team found that the immune system of those with CRS was activated by the microbiota of healthy individuals.

Further study findings suggested that bacteria and fungi are not causing an infection in the sinuses, but rather, that the immune system was responding to commensals, microorganisms that, themselves, do not harm the human body. When the immune system reacts in a hyper-responsive way, unnecessarily fighting off a harmless microorganism, it can initiate an immune response like inflammation. The body can then get locked into a cycle where inflammation generates more inflammation, causing a chronic condition.

"Patients with CRS are hyper-responsive to normal microbiota," said Aurora. "Our take-home message is that the problem doesn't lie in the microbiota. The inflammatory response and the resulting damage from the prolonged inflammation are caused by the body's own immune response to harmless microbiota."

For future studies, Aurora is left with another important question to answer. If the immune system is activated in response to commensals, why are only nasal and sinus microbiota and not those in the gut or skin involved?

There is no evidence, for example, that people with CRS also have colitis, another inflammatory condition. It appears that there is some specificity to the reaction to the microbiota in the nasal passages, and future research will explore why the inflammatory reaction appears to be so localized.


'/>"/>

Contact: Carrie Bebermeyer
bebermcl@slu.edu
314-977-8015
Saint Louis University
Source:Eurekalert  

Related biology news :

1. Sinusitis linked to microbial diversity
2. A solution to sinusitis from the sea
3. With new study, aquatic comb jelly floats into new evolutionary position
4. From scourge to saint: E. coli bacteria becomes a factory - to make cheaper, faster pharmaceuticals
5. Vitamin D holds promise in battling a deadly breast cancer, Saint Louis University researchers say
6. In a fight to the finish, Saint Louis University research aims knockout punch at hepatitis B
7. Saint Louis University, University of Toronto biologists help decode turtle genome
8. Saint Louis University researchers discover a way to detect new viruses
9. Research by Saint Louis University scientists offers way to disrupt fibrosis
10. BP Deepwater Horizon oil spill exacerbated existing environmental problems in Louisiana marshes
11. SMU professor Louis Jacobs honored with prestigious award from Texas science teachers
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
With sinus study, Saint Louis University researchers find that harmless members of microbiome spark immune reaction
(Date:6/9/2016)... leader in attendance control systems is proud to announce the introduction of fingerprint attendance ... the right employees are actually signing in, and to even control the opening of ... ... ... Photo - ...
(Date:6/2/2016)... NEW YORK , June 2, 2016   The ... (Weather), is announcing Watson Ads, an industry-first capability in which ... advertising, by being able to ask questions via voice or ... Marketers have long ... with the consumer, that can be personal, relevant and valuable; ...
(Date:5/16/2016)... , May 16, 2016   EyeLock LLC , ... announced the opening of an IoT Center of Excellence ... and expand the development of embedded iris biometric applications. ... level of convenience and security with unmatched biometric accuracy, ... identity aside from DNA. EyeLock,s platform uses video technology ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... , June 23, 2016  Blueprint Bio, a company ... to the medical community, has closed its Series A ... Nunez . "We have received a commitment ... capital we need to meet our current goals," stated ... us the runway to complete validation on the current ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, a ... designed, tuned and optimized exclusively for Okuma CNC machining centers at The International ... a collaboration among several companies with expertise in toolholding, cutting tools, machining dynamics ...
(Date:6/22/2016)...  According to Kalorama Information, the dominant trends ... include significant efforts in automation as well as ... affordable sequencers, say the healthcare market research firm, ... sample prep materials.  The healthcare market research company,s ... Next Generation Sequencing (NGS) , highlights major trends ...
(Date:6/22/2016)... ... June 22, 2016 , ... The Immigrant ... achievements and contributions to North Texas and the nation, recently held its annual ... community to the civic and economic vitality of North Texas. Proceeds from the ...
Breaking Biology Technology: