Effects of Components of PM2.5 Collected in Japan on the Respiratory and Immune Systems.

Epidemiologic studies have reported that particulate matter with aerodynamic diameters ≤2.5 µm (PM2.5) affect respiratory diseases, including asthma. The components and/or factors of PM2.5 that contribute to the exacerbation of asthma have not been identified. We investigated the effects of extracts of PM2.5 collected in Japan on the respiratory and immune systems. PM2.5 was collected from an industrial area and an urban area in December 2013. Airway epithelial cells and immune cells were exposed to aqueous or organic extracts of PM2.5. Exposure to extracts from both areas, especially to organic extracts rather than aqueous extracts, caused a pro-inflammatory response via interleukin (IL) 6 production from airway epithelial cells, and it induced the maturation/activation of bone marrow-derived antigen-presenting cells via dendritic and epithelial cell (DEC) 205 and cluster of differentiation (CD) 86 expression and proportional changes in the constitution of the splenocytes. The extracts collected from the industrial area tended to show greater effects than those from the urban area. These results suggest that organic components of PM2.5 affect the respiratory and immune systems. These effects can differ by the collection areas. In addition, IL-6, DEC205, and CD86 can be predictive biomarkers for the respiratory and immune effects of ambient PM2.5.

Biological factor related to Asian sand dust particles contributes to the exacerbation of asthma.

Epidemiologic studies have revealed that Asian sand dust particles (ASDs) can affect respiratory and immune health represented by asthma. Factors responsible for the exacerbation of asthma remain unclear. The fungus Bjerkandera adusta (B.ad) and polycyclic aromatic hydrocarbons such as benzo[a]pyrene (BaP) have been identified in ASDs collected from the atmosphere when an ASD event occurred. We investigated the effects of B.ad and BaP related to ASDs on respiratory and immune systems. Bone marrow-derived antigen-presenting cells (APCs) and splenocytes from atopic prone NC/Nga mice and human airway epithelial cells were exposed to the B.ad or to BaP in the presence and absence of heated-ASDs (H-ASDs). B.ad and BaP in both the presence and absence of H-ASDs increased the expression of cell surface molecules on APCs. H-ASDs alone slightly activated APCs. The expressions induced by B.ad were higher than those induced by BaP in the presence and absence of H-ASDs. There were no remarkable effects on the activation of splenocytes or the proinflammatory responses in airway epithelial cells. These results suggest that B.ad rather than BaP contributes to the exacerbation of asthma regardless of the presence or absence of sand particles, particularly by the activation of the immune system via APCs. Copyright © 2016 John Wiley & Sons, Ltd.

Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan.

Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7µg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10µg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in <3weeks hospitalization or no hospitalization) when compared to severe medical conditions (e.g. critical cases, and cases that led to >3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being.