Navigation Links
Asthma tied to bacterial communities in the airway

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.

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 diseaseThis 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.


Contact: Elizabeth Fernandez
University of California - San Francisco

Related biology news :

1. Family mealtimes play a role in health of children with asthma
2. More research needed on diet and environmental influences on childhood asthma
3. Young people with asthma run a greater risk of developing caries
4. New asthma research breaks the mold
5. Discovery of taste receptors in the lungs could help people with asthma breathe easier
6. Possible alternate therapy for adults with poorly controlled asthma
7. Research and insights on severe asthma in children
8. Study points to key genetic driver of severe allergic asthma
9. Asthma and eczema sufferers have a lower risk of developing a cancer
10. Ultrafine particles in air pollution may heighten allergic inflammation in asthma
11. Study of severe asthma using CT scans
Post Your Comments:
(Date:11/18/2015)... 18, 2015 --> ... new market report titled  Gesture Recognition Market - Global ... - 2021. According to the report, the global gesture recognition market was ... to reach US$29.1 bn by 2021, at a CAGR ... North America dominated the global gesture recognition ...
(Date:11/16/2015)... Calif. , Nov 16, 2015  Synaptics ... of human interface solutions, today announced expansion of ... TouchView ™ touch controller and display driver ... revolution of smartphones. These new TDDI products add ... TD4100 (HD resolution), TD4302 (WQHD resolution), and TD4322 ...
(Date:11/10/2015)... 10, 2015  In this report, the ... of product, type, application, disease indication, and ... report are consumables, services, software. The type ... biomarkers, efficacy biomarkers, and validation biomarkers. The ... diagnostics development, drug discovery and development, personalized ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... - ProMetic Life Sciences Inc. (TSX: PLI) (OTCQX: PFSCF) ("ProMetic" ... , President and Chief Executive Officer of ProMetic, will be ... th Annual Healthcare Conference to be held at the ... st , at 8.50am (ET) and ProMetic,s management team ... presentation will be available live via a webcast accessible at ...
(Date:11/24/2015)... ... ... Whitehouse Laboratories is pleased to announce that it has completed construction on a ... basic USP 61, USP 62 and USP 51 testing specific to raw materials and ... testing performed by one supplier. Management has formally announced that the facility ...
(Date:11/23/2015)... , ... November 23, 2015 , ... ... for the development of its Nexera UC Unified Chromatography system. The award from ... technically significant new products of the year in the analytical and testing category. ...
(Date:11/23/2015)... , Nov. 23, 2015  CryoLife, Inc. (NYSE: CRY ... on cardiac and vascular surgery, announced today that it will ... Healthcare Conference on Wednesday, December 2, 2015 at The New ... . Pat Mackin , President and Chief Executive ... Chief Executive Officer. --> A live webcast ...
Breaking Biology Technology: