Faculty Bibliography

OBJECTIVES: Particulate matter (PM) exposure causes adverse health effects. The WTC collapse led to significant PM exposure and lung injury (Weiden et al. Chest 2009). The mechanism by which WTC PM causes pulmonary morbidity is not understood. We are investigating the differential cytokine effects on human alveolar cells, comparing ambient PM of WTC to ambient PM from NYC, South Bronx (SB) and Sterling Forest (SF), a rural area northwest of NYC. METHODS AND POPULATION: AM were obtained from Bronchoalveolar lavage (BAL) by adherence overnight. AM were exposed to 50mug/mL suspensions of WTC, SB, and SF PM2.5. Media alone was the negative control and 40 ng/mL of LPS was the positive control. After 24hrs, supernatants were collected and analyzed in duplicate using Human Cytokine Panel I (Millipore) on a Luminex-200. RESULTS: Fold induction of mediators was expressed as ratios of PM exposure/media alone. Exposure to WTC PM was markedly more inflammatory than SB and SF. The most significant inductions were of the leukocyte growth factors (GM-CSF, G-CSF), a promoter of angiogenesis (VEGF), the chemokine (RANTES) and the potent multifunctional cytokine IL-6. LPS caused a greater induction for all of the analytes when compared to WTC PM except for IL-1ra. SIGNIFICANCE OF STUDY: WTC PM2.5 produces a marked inflammatory effect in comparison to PM2.5 from both NYC, SB and rural sites. The large number of cytokines induced by WTC PM may drive airway injury and may be biomarkers for lung injury. WTC PM has been observed in induced sputum obtained 9 months after 9/11/2001 and so the elaboration of cytokines may underlie the severe and long lasting health effects produced by exposure to WTC PM