Biochips help reduce the need for animal testing

US researchers have developed a new biochip technology that could dramatically reduce the need for animal testing during drug development safety studies.

Toxicity testing has traditionally relied on animal testing procedures to predict whether a drug candidate is toxic or not, but these expensive animal tests do not always accurately mimic human responses to compounds.

There has been a growing effort by various groups to develop strategies that replace or minimise the number of animal tests needed to be conducted on a compound during preclinical trials.

The new biochip technology, developed by a team of researchers at Rensselaer Polytechnic Institute, the University of California at Berkeley, and Solidus Bioscience will be described in an upcoming Early Edition of the online journal Proceedings of the National Academy of Sciences (PNAS).

"We looked at the issues facing companies and realised that we needed to develop something that was low-cost, high-throughput, easily automatable, and did not involve animals," said co-lead author Professor Jonathan Dordick of the Rensselaer Polytechnic Institute and co-founder of Solidus Biosciences.

The DataChip comprises over 1000 three dimensional tissue cultures that mimic how cells would be arranged in the body to provide researchers with a fast screening system capable of predicting the potential toxicity of a drug candidate to various organs.

The MetaChip was described in a previous paper in the same journal and mimics the metabolic reactions of the human liver where seemingly benign chemicals can become highly toxic.

"We developed the MetaChip and DataChip to deal with the two most important issues that need to be assessed when examining the toxicity of a compound - the effect on different cells in our body and how toxicity is altered when the compound is metabolised in our bodies," said Prof. Dordick.

An individual's ability to metabolise a compound is determined by their genetic make-up with the amount of drug-metabolising enzyme expressed determining how toxic a particular compound may be to them.

By varying the ratios of enzymes on the MetaChip, scientists could develop personalised chips that predict a patient's response to a particular compound.

"We are still a ways off from personalised medicine, but the MetaChip offers that future possibility," said Prof. Dordick.