Development of a Toxicity Evaluation System for Gaseous Compounds Using Air-liquid Interface Culture of a Human Bronchial Epithelial Cell Line, Calu-3

Yasuyuki Sakai1,2, Kengo Tomita2,3, Motoyuki Suzuki2,4, Yoshiro Ono5 and Akiyoshi Sakoda2
1 Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 114-0033, Japan
2 Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
3 Current affiliation: Environmental Science Center, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 114-0033, Japan
4 Current affiliation: United Nations University, 5-53-70 Jingu-mae, Shibuya-ku, Tokyo 150-8558, Japan
5 Department of Environmental Engineering, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

AATEX 11(1):59-67, 2005

To mimic in vivo condition for exposure to gaseous compounds, we employed the Air-Liquid Interface Culture (ALIC) of a human bronchial epithelial cell line, Calu-3, and developed a simple batch-type closed system for direct gas exposure. This system en-abled relatively simple cytoxicity evaluation of various gaseous chemicals in an in vivo mimicking manner. As a preliminary evaluation of the system developed, we tested the toxicity expression of Calu-3 to benzene, tetrachloroethylene and acetone gases in terms of lactate dehydrogenase (LDH) release during 48 hours of the loading. The toxicity in ALIC exposure was higher than that in conventional exposure in the liquid phase. The reason was largely explained by numerical estimation that chemical concentrations ex-actly on the cell surface in the liquid culture is lower in such acute phase exposure than that in ALIC culture, in the cause of the diffusion process of molecules in the surface liq-uid layer. These results indicate that basic concept of the combination of ALIC of lung cells and a simple batch-type closed system is promising as a cytotoxicity test of wide ranges of gaseous compounds or samples.

Key words: Cytotoxicity, Exposure system, Gaseous compound, Air-liquid interface culture (ALIC), Calu-3 cell