To simply evaluate toxicity for various types of exhaust-gas samples collected in various locations, we developed a smallscale (150 mL) batch-type completely closed gas exposure device incorporated with an air-liquid interface culture of a human alveolar epithelial cell line, A549. On the basis of cell viability tests using an acid phosphatase assay after 48 h of gas exposure, the developed device was able to measure clear dose-response relationships for volatile organic and inorganic compounds, such as benzene, trichloroethylene (TCE), acetone, SO2 and NO2 gases, but not CO gas. Although the 50% effective concentration values in the device were much higher than 50% lethal concentration values reported in animal experiments, the tendency of the toxic intensity observed in the former was roughly consistent with that of the acute toxicity in the latter. We further applied the device to evaluate the toxicity of cigarette smoke as an example of actual environmental gases, and successfully measured acute cell death from the gas after 48 h of exposure. The present small device is expected to be one of good tools not only in simultaneously assessing various gaseous chemicals or samples, but also in studying acute toxicity expression mechanisms in human lung epithelia.
Conventional in vitro cytotoxicity tests usually do not include toxicokinetic processes that aŠectˆnal toxicity in the entire body. To overcome this limitation, we have been developing several types of new toxicity test systems and applying them to evaluate hazardous chemicals or environmental samples. In this review, we described two of these new systems; one is a batch-type gas exposure system based on air-liquid interface culture of lung epithelial cells, and the other is a simple double-layered coculture system incorporating permeation and biotransformation processes occurring in the small intestine. In addition, we introduce our latest approach toward further miniaturization of existing tests, that is, determination of minimum cell number necessary for obtaining physiologically-relevant tissue responses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.