We are at the right place at the right time to help advance the explosion of research on mouse models of human disease

Dr Allan Johnson

The researchers, from Duke University Medical Center in North Carolina, have perfected the technique, known as magnetic resonance microscopy (MRM).

They believe it could be a powerful new tool for exploring the effects of gene technology experiments on mice - and in turn what the likely effect would be on humans.

The researchers plan to create an extensive library of mouse images which could be transmitted over high speed internet connections.

This would enable scientists to "share" the animals electronically, and to digitally "slice" the animals in a variety of ways to explore their anatomy.

A team of researchers separated by thousands of miles could therefore electronically dissect the same animal simultaneously, and discuss their insights via videoconferencing.

Example

Writing in the journal Radiology, the researchers, led by Dr Allan Johnson, describe how they used the new technology to produce scan images of a mouse at a resolution of 110 microns.

They were also able to zoom in to scan individual organs at a resolution of 25 microns.

3D hinged image of a mouse kidney

By comparison, the width of a human hair is about 200 microns.

Basically, MRM, like MRI, involves subjecting animals to high magnetic fields that, while harmless, cause the alignment of protons in the molecules of their tissues.

Radio frequency pulses are used to perturb and probe the tissues.

By using sensitive radio frequency detectors to map the distinctive response of different tissues to such perturbation, the researchers can create high-resolution images that reveal whole organs as well as the structures within the organs.

Dr Johnson said: "With MRM technology, we are at the right place at the right time to help advance the explosion of research on mouse models of human disease.

"Physically slicing and staining mouse sections is enormously expensive and severely limits exploration of the often diverse morphological impacts of genetic alteration of these mice.

"Thus, we believe that we will provide a powerful new tool for molecular biologists, geneticists, toxicologists, pathologists - any scientist using mouse models."

Advantages

Dr Johnson said the MRM technology had a number of benefits over conventional techniques.

It enables scientists to study the whole animal more easily to find out whether gene manipulation has had effects in unexpected areas.

It is also free of the problems of sample dehydration that blight traditional staining techniques.

Some six million transgenic and knockout mice were produced for research last year.

Transgenic mice are those in which a gene has been altered, and knockout mice are those in which the gene function has been eliminated.

Dr Johnson has founded a company, MRPath Inc, to offer MRM scanning services and viewing software to the research community.