Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Virus in babies may cause asthma later on

11.07.2002

While most scientists believe that allergies cause asthma, researchers at Washington University School of Medicine in St. Louis are uncovering a second potential cause for this common respiratory illness. Their new model suggests that a viral infection in the first years of life may leave a lasting mark on the immune system, causing chronic respiratory problems later on.

"While the allergic response may increase during an asthma attack, our research suggests that the anti-viral response also increases," says Michael J. Holtzman, M.D., the Selma and Herman Seldin Professor of Medicine and professor of cell biology and physiology. "We think that a virus in infancy or childhood creates a hit-and-run effect, where a brief infection causes permanent changes in the body’s anti-viral system."

Holtzman led the study, which appears in the July 15 issue of the Journal of Clinical Investigation.

The most common cause of lower respiratory illness in children is paramyxoviral infection, which often results in chronic wheezing regardless of whether the child develops allergies. But researchers have yet to figure out how the short-term influence of this viral infection leads to a long-term condition of respiratory inflammation and distress.

Holtzman’s team examined mice with bronchiolitis – inflamed airways – caused by paramyxoviral infection. The mouse disease mimics paramyxoviral infection in humans. These mice responded immediately to the infection – immune cells flooded the lining of the respiratory tract, attacking infectious cells and inflaming the tissues. Weeks after infection, the airways of the lung remained extremely sensitive, or hyperreactive, and the airway lining became populated with mucus-producing cells. Each of these changes – airway hyperreactivity and cellular remodeling – lasted for at least one year and perhaps indefinitely. "Since each of these changes also is a long-term symptom of asthma, these findings provide a link between the response to viral infection and the development of asthma," says Holtzman.

Uninfected mice that instead were exposed to a common experimental allergen, called ovalbumin, also developed similar inflammation of the airways, but these mice recovered by themselves within two and a half months.

To see what happens if the initial airway response was prevented, the researchers examined mice lacking the gene that encodes one of the main proteins that control immune-cell traffic, intercellular adhesion molecule-1 (ICAM-1). As expected, mice lacking ICAM-1 that were infected with this virus were initially healthier than their normal counterparts, with far less airway inflammation, less weight loss and lower mortality rates.

Interestingly, though, these genetically altered mice still developed chronic asthma-like changes similar to normal mice – they reached the same level of airway hyperreactivity and mucus-producing cells as normal mice by 11 weeks after infection.

The team also discovered that mice treated with glucocorticoid, a common anti-asthma medication, before cellular remodeling began were at least partially protected from the chronic effects of viral infection.

"Our findings raise the possibility that asthma not only resembles a persistent anti-viral response, but may actually be caused by one," says Holtzman. "These results in mice provide a further basis for determining exactly how similar events may develop in children and adults with asthma."

###

Walter MJ, Morton JD, Kajiwara N, Agapov E, Holtzman MJ. Viral induction of a chronic asthma phenotype and genetic segregation from the acute response. Journal of Clinical Investigation, Vol. 110, pg. 165 – 175, July 15, 2002.

Funding from the National Heart, Lung and Blood Institute, the American Lung Association, the Martin Schaeffer Fund and the Alan A. and Edith L. Wolff Charitable Trust supported this research.

The full-time and volunteer faculty of Washington University School of Medicine are the physicians and surgeons of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient-care institutions in the nation. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Gila Reckess | EurekAlert

More articles from Health and Medicine:

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

nachricht The gut microbiota plays a key role in treatment with classic diabetes medication
01.06.2017 | University of Gothenburg

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>