New tool to measure toxicity in smokers

A three-dimensional model of human respiratory tissue can offer an improved platform to measure the impact of chemicals, like those found in cigarette smoke, or other aerosols on the lung, a new study says.

The tissue model that the researchers assessed is called MucilAir. Traditional lab-based tests use cell lines that do not reflect normal lung structure and physiology, and in some cases have reduced, or loss of, key metabolic processes, the researchers noted.

Consequently, the long-term toxicological response of the cells can differ from what actually happens in humans, the study to be published in the journal Toxicology in Vitro noted.

"The combined weight of evidence from proteomics, gene expression and protein activity demonstrates that the MucilAir system is far better than continuous cell lines for assessing the effect of repeated exposure to inhaled chemicals and toxicants," says Emmanuel Minet, senior scientist at British American Tobacco.

The scientists assessed the effectiveness of MucilAir by growing human respiratory epithelial cells at the air-liquid interface on nasal cells.

The results showed that the cells in the test model remained viable for at least six months, which makes this tissue model suitable for testing the impact of repeated exposures over a prolonged period, as in the case of the typical smoker.

"Our results give clear supporting evidence that MucilAira, has the potential to be used to test not only the effect of acute doses of toxicants and medicines but also the effect of repeated doses over time," the researchers noted.