A Faster Screen for Toxicity

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Any type of cell can be included in the DataChip, so "you can be predictive not only against a liver cell, which most technologies now deal with, but go beyond the liver to other organ types," Dordick says. For example, skin cells could be used to rapidly screen new chemicals and cosmetics for skin toxicity.

The individual cell cultures on the chip are contained within blobs of hydrogel on the glass slide, which allows the human cells to grow in a three-dimensional way. That's important when mimicking how a compound will affect real tissues in the body, Dordick says.

To be sure, the new technology faces many challenges before it becomes an accurate drug-screening method. For one thing, the DataChip assesses toxicity by looking at how compounds affect cell growth. But growth can also be affected by the cells' environment, in this case the hydrogel, says Linda Griffith, director of the Biotechnology Process Engineering Center at MIT, whose group is working on liver models that would be used at a later stage in the drug-development process. For example, the researchers tested the DataChip with cells from a breast-cancer cell line, and research from other labs has shown that the mechanical properties of the matrix drive cell signaling and gene expression, Griffith says.

But despite such limitations in drug testing, the new combination of biochips could be useful as an early screening tool for drug candidates. Even more immediate, say the RPI and Berkeley researchers, the combination could provide a quick and easy way to screen cosmetics without animal testing.