Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Asthma tied to bacterial communities in the airway

18.02.2011
Asthma may have a surprising relationship with the composition of the species of bacteria that inhabit bronchial airways, a finding that could suggest new treatment or even potential cures for the common inflammatory disease, according to a new UCSF-led study.

Using new detection methods, researchers learned that the diversity of microbes inside the respiratory tract is far vaster than previously suspected – creating a complex and inter-connected microbial neighborhood that appears to be associated with asthma, and akin to what has also been found in inflammatory bowel disease, vaginitis, periodontitis, and possibly even obesity.

Contrary to popular belief, the scientists also learned that the airways are not necessarily entirely sterile environments, even in healthy people, while the airways of asthmatics are infected by a richer, more complex collection of bacteria. These findings could improve understanding of the biology of asthma, and potentially lead to new and much-needed therapies.

"People thought that asthma was caused by inhalation of allergens but this study shows that it may be more complicated than that – asthma may involve colonization of the airways by multiple bacteria,'' said study co-author Homer Boushey, MD, a UCSF professor of medicine in the division of Pulmonary and Critical Care Medicine.

The study is published online in the Journal of Allergy and Clinical Immunology. http://www.jacionline.org/issues?issue_key=S0091-6749(10)X0018-5

Asthma is one of the most common diseases in the world, with approximately 300 million asthmatics globally, including 24 million in the United States, according to the Centers for Disease Control. The disease has been on the rise for the last 60 years.

"It has gone from 3 percent of the population to slightly more than 8 percent of the population in the U.S.,'' said Boushey. "It is most prevalent in western, developed nations – and we don't know why.''

In recent years, scientists began studying communities of mixed-species microorganisms (microbiome) found in both diseased and healthy people to better understand their role in a variety of diseases. But research on the microbiome in respiratory disease is relatively uncharted terrain.

"We know fairly little about the diversity, complexity and collective function of bacteria living in the respiratory tract, and how they might contribute to diseases like asthma,'' said Yvonne J. Huang, MD, the paper's first author. She is a research fellow and clinical instructor in the UCSF Pulmonary Division.

"Traditionally, the airways have been thought to be sterile. However, this study suggests this is not the case. Certain asthma patients who require inhaled corticosteroid therapy possess a great abundance of bacteria compared to healthy individuals, and have an increased relative abundance of specific organisms that is correlated with greater sensitivity of their airways.''

In their three-year pilot project, the scientists collected samples from the airway linings of 65 adults with mild to moderate asthma and 10 healthy subjects. Then, using a tool that can identify approximately 8,500 distinct groups of bacteria in a single assay, the scientists profiled the organisms present in each sample to look for relationships between bacterial community composition and clinical characteristics of the patients' asthma.

The researchers found that bronchial airway samples from asthmatic patients contained far more bacteria than samples from healthy patients. The scientists also found greater bacterial diversity in the asthmatic patients who had the most hyper-responsive or sensitive airways (a feature of asthma).

"People have viewed asthma as a misdirected immune reaction to environmental exposures, but few have thought of it in the context of airway microbiota composition,'' said senior author Susan Lynch, PhD, an assistant professor of medicine and director of the UCSF Colitis and Crohn's Disease Microbiome Research Core in the division of gastroenterology.

"We took an ecological approach, considering the bacteria in the context of their microbial neighborhoods to identify relationships between characteristics of these communities and features of the disease…This new approach will help us to better understand the microbiota-host relationships that define human health.''

The authors say that further studies are needed to determine how these specific bacteria identified in the study may influence the cause and development of asthma.

The study was supported by the National Heart, Lung and Blood Institute and by the Strategic Asthma Basic Research Center at UCSF, supported by the Sandler Family Foundation. Huang was funded by a National Institutes of Health grant and by a UC Tobacco-related Disease Research Program award; Lynch receives research support from the NIH; Boushey is an ad-hoc consultant for KaloBios Pharmaceuticals, Inc., is on the advisory committee for Pharmaxis, is on ad-hoc advisory committees for GlaxoSmithKline and Merck, and receives research support from GlaxoSmithKline.

UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care.

Follow UCSF on Twitter at http://twitter.com/ucsf

Elizabeth Fernandez | EurekAlert!
Further information:
http://www.ucsf.edu

More articles from Health and Medicine:

nachricht New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia

nachricht New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>