Pulmonary Health Effects of Ai...

Pulmonary Health Effects of Air Pollution: Particulate Matter and Allergic Arway Inflammation

Airborne particulate matter (PM) exposure is one of the major risk factors for increased respiratory morbidity and mortality in urban environment.  Epidemiological evidence has indicated that there is a close association between PM and the prevalence of allergic diseases such as asthma.  Among PM of different sizes, ultrafine particles (UFP) are far more dangerous to human health than larger particles.  Due to their small size and large surface area, UFP have great ability to carry a large amount of organic chemicals and deposit them in the lung.  Many of the organic chemicals on UFP surface are capable of generating reactive oxygen species (ROS) and causing cellular oxidative stress, which may lead to inflammation and cell death.  PM contributes to the pathogenesis and exacerbation of allergic airway inflammation through its pro-allergic and pro-inflammatory effects.  One of the mechanisms is that PM can act as an adjuvant to enhance allergic sensitization to common allergens by targeting dendritic cells, the major antigen presenting cells in the immune system.  Another potential mechanism is that PM (e.g. ambient UFP) can boost the secondary immune response during allergen re-exposure, resulting in a more profound inflammatory response deep in the lung.  Experimental evidence has suggested that these effects are closely correlated to particles’ organic chemical contents and oxidant potential.  Taken together, these findings may explain the importance of vehicular traffic on the pathogenesis and exacerbation of allergic airway inflammation, especially in urban settings, and provide an insight to developing preventive and therapeutic strategies for air pollution-related allergic airway diseases (e.g. asthma and allergic rhinitis).

Presentation Type: 
Invited Presentation
Author 1: 
Ning Li
Additional Authors: 
no more authors
Author Roles
Corresponding Author: 
Ning Li
Presenting Author: 
Ning Li