Measurement for Investigating Aerosol Toxicity, Using Centrifugal Classification of Suspended Particles for Cell Exposure and in Vitro Evaluation Using Thp-1 Macrophages
KAKO OGANE, Ayumi Iwata, Tomoaki Okuda,
Keio University Abstract Number: 51
Working Group: Health-Related Aerosols
AbstractAirborne particulate matter (PM) is of a global public health concern due to a variety of adverse health effects. Evaluation of the health effects of PM should reflect physicochemical properties especially size. Among various methods, in vitro models are often used as a convenient screening procedure for assessing the adverse effects of air pollutants including PM. For in vitro testing, we need to prepare suspensions composed of PM. In this study, we made a method of size-fractionated particle suspension using centrifuge and we investigate the effects of size-fractionated suspension PM on THP-1 cells in relation to their physicochemical properties.
We used THP-1 cells differentiated with phorbol 12-myristate 13-acetate (PMA) as a model for macrophages in the survey. THP-1 cell line was exposed by copper particles with six different diameters (concentration: 5, 10, and 50 µg/mL for 24 h) to measure cell viability using a colorimetric assay for 96-well plates with 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium monosodium salt (WST-1). Each different sizes of cooper median diameter were 1.15, 4.47, 5.12, 26.1, 34.3 and 77.3 μm. In addition, we classified the sizes of 4.47 μm by centrifugal to those with 1.15 and 5.12 μm.
Copper particles with 1.15, 4.47 and 5.12 μm produced greater cellular toxicities, considering the decrease in the cell viabilities rather than 26.1, 34.3 and 77.3 μm (p < 0.05). The results demonstrated that size distribution of aerosol and surface area are key parameters for the extent of PM toxicity, particularly in the case of the smaller particles. This method can be useful to investigate the toxicity for ambient air particles in terms of physicochemical properties.