A new academic study led by UCLA scientists has found that even brief exposure to ultrafine pollution particles near a Los Angeles freeway is potent enough to boost the allergic inflammation that exacerbates asthma.
Published online in the American Journal of PhysiologyLung Cellular and Molecular Physiology in June, the study shows that the tiniest air pollutant particles ― those measuring less than 180 nanometers, or about one-thousandth the width of a human hair ― incited inflammation deep in the lungs. The researchers used a "real-time" testing method in an animal model to isolate the effects of vehicular emission particles on the immune response in the lung.
Since these ultrafine particles are primarily derived from vehicular emissions and are found in highest concentrations on freeways, the results have particular significance for the study of the impact of traffic-related emissions on asthma flares in urban areas.
The findings also point to the importance of understanding the role air-pollution particles play in asthma flares in order to develop new approaches for asthma therapy.
"The immune processes involved in asthma, and current treatments, are traditionally thought to be dominated by a specific initial immune response, but our study shows that ultrafine pollution particles may play an important role in triggering additional pathways of inflammation that heighten the disease," said the study's principal investigator, Dr. Andre E. Nel, professor of medicine and chief of nanomedicine at the David Geffen School of Medicine at UCLA.
Pollution particles emitted by vehicles and other combustion sources are coated with a layer of organic chemicals that can be released into the lungs. These chemicals generate free oxygen radicals, which excite the immune system in the lung through a cell- and tissue-
damaging process known as oxidation. Oxidation contributes to allergic
|Contact: Rachel Champeau|
University of California - Los Angeles