TY - JOUR T1 - Engineered nanoparticles induce apoptosis of human bronchial epithelial cells JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p766 AU - Hasan Bayram AU - Bulent Gogebakan AU - Recep Bayraktar AU - Ahmet Arslan Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p766.abstract N2 - Engineered nanoparticles are widely used by the industry, however, it is not clear whether they posses a risk on respiratory health. The objectives of our study were to investigate effects of Titanium dioxide (TiO2) and multi walled carbon nanotubes (MWCNT) on bronchial epithelial cell (BEC) viability and death. BEAS-2B cells and primary BEC obtained from both smokers and patients with COPD were incubated with 0-300μg/ml TiO2 and MWCNT for 24-48hrs. Cell viability was assessed by MTT, and apoptosis was analyzed by flow cytometry using Annexin V-PE and 7AAD dyes. TiO2 significantly decreased the viability of BEAS-2B cells at 100 (optical density [OD]=0.65; p<0.0001) and 300μg/ml (OD=0.45; p<0.0001) concentrations after 24hrs as compared control cells (OD=0.85). Similarly, 100 and 300μg/ml MWCNT decreased viability of these cells following 24 and 48hrs' incubation. Although 30μg/ml TiO2 induced the viability of primary BEC of smokers (OD=2.15 vs OD=1.52; p<0.0001), 300μg/ml suppressed cell viability (OD=1.02; p<0.0001) after 24hrs. TiO2 did not change the viability of BEC of COPD patients after 24hrs, whereas 300μg/ml decreased viability of these cells (OD=0.40 vs 1.72; p<0.001) following 48hrs. Flow cytometry studies of BEAS-2B cells demonstrated that TiO2 (300μg/ml) decreases percentage of viable cells (90.66% vs 94.01%; p= 0.0009), while inducing the percentage of late apoptotic (0.72% vs 0.42%; p=0.017) and necrotic (6.63% vs 4.03%; p=0.0009) cells. MWCNT also showed similar effects on apoptosis of BEAS-2B cells. These findings suggest that engineered nanoparticles may possess a risk on respiratory health by modifying viability and apoptosis of bronchial epithelial cells. ER -