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 Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

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 the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>