Written on Sunday, May 11, 2008 by Gemini

Researchers at the US Department of Energy’s Argonne National Laboratory have developed a chip that can save lives by diagnosing certain cancers even before patients become symptomatic. A tumour – even in its earliest asymptomatic phases – can affect proteins that find their way into a patient’s circulatory system. These proteins trigger the immune system to kick into gear, producing antibodies that regulate which proteins belong, and which do not.

-- Picture: Argonne biologist Daniel Schabacker prepares to load a biochip onto a scanner. The biochip (below) contains grids of small wells or ‘dots’, each of which contains a protein, antibody or nucleic acid, which helps detect cancer. --

The new technology, known as a biochip, consists of a 1x1 cm array that comprises anywhere between several dozen and several hundred ‘dots’, or small drops. Each of these drops contains a unique chemical that will attach itself to particular proteins that could be cancer tell-tales. “Antibodies are the guardians of what goes on in the body,” said Tim Barder, president of US-based Eprogen, Inc, which has licensed Argonne’s biochip technology. “If a cancer cell produces aberrant proteins, then it’s likely that the patient will have an antibody profile that differs from that of a healthy person,” he added.

In their hunt for cancer indicators, Eprogen uses a process, which sorts thousands of different proteins from cancer cells by both their electrical charge and their hydrophobicity or “stickiness.” The process creates 960 separate protein fractions, which are then arranged in a single biochip containing 96-well grids. Scientists then probe the microarrays with known serum or plasma “auto-antibodies” produced by the immune systems of cancer patients.

By using cancer patients’ own auto-antibodies as a diagnostic tool, doctors could potentially tailor treatments based on their personal auto-antibody profile. What makes this technique unique is that scientists can use the actual expression of the patient’s disease as a means of obtaining new and better diagnostic information that doctors could use to understand and fight cancer better. Biochips have already shown promise in diagnostic medicine and are useful in rapidly and accurately detecting other diseases, said Argonne biologist Daniel Schabacker, who developed the technology.