B.F.D

The Doctor Will See Your Prototype Now

How super-accurate sims can test the effects of drugs on patients.

To Peter Hunter, the future of medicine looks like this: You visit your doctor after weeks of feeling fatigued and lethargic. She takes a blood sample, records your DNA profile, does a quick CT body scan, then uploads the raw data to a workstation. Within minutes, software stitches together a head-to-toe living, breathing digital reproduction of your innards, which the doc can poke and prod just like the real thing. Turns out you have lung cancer. Rather than focusing on one treatment, your physician can test various scenarios on your digital doppelgänger - surgery, radiation, chemotherapy - and watch how your system reacts. The cure is the simulation that doesn't kill the virtual you.

Hunter, director of the Bioengineering Institute in Auckland, New Zealand, is an expert in biomechanics and in computational physiology, an emerging field. He admits that his vision for health care might be a decade or two away, but it's by no means science fiction. Bioengineers in the institute's Physiome Project are assembling digital models of every system and anatomical feature of the human body - from large organs to tiny cellular and molecular functions.

Hunter and his colleagues have already finished a draft of the skeletal system, and they recently built the first-ever digital human heart and lungs. The lungs - with 300 million alveoli - inhale and exhale just like flesh-and-blood ones. Meanwhile, work is under way on a replica of the digestive system and a comprehensive database of cellular functions. Other system models - nervous, endocrine, immune, sensory, skin, kidney-urinary, reproductive - are coming.

The process for creating the models is surprisingly literal, even crude. Hunter's team built a contraption for slicing off razor-thin layers of cadaver flesh - heart and lung tissue, for instance - which can be scrutinized under a microscope or fed through a digital scanner. Another device, called a multiaxial rig, looks like a roulette wheel made from an Erector set. It's used to assess the tensile strength of human skin and other soft tissue.

The scientists in Auckland have plenty of help. The Physiome Project is a worldwide initiative, akin to the Human Genome Project, with a dozen research teams participating at labs across the US and in Israel, Japan, and the UK. Hunter compares his project to the evolution of Linux: "Physiome is so big and so important that it needs an underlying open source framework."

Pharmaceutical companies are hovering over the research. Hunter says he's met with execs from Aventis and Novartis. And no wonder: Once perfected, the technology would allow drugmakers to develop and test the effectiveness of medicines before forking out billions of dollars for risky clinical trials. Physiome would also enable medical engineers to fashion customized implants, such as pacemakers or artificial heart valves. And it would let surgeons make dry runs on a digital replica of their patient - determining which technique works best before ever picking up a knife. "Today practically everything we see and touch was prototyped by computers," says Randy Haluck, director of minimally invasive surgery and surgical simulation at Penn State Hershey Medical Center. "One glaring exception is in medicine - but there's no reason to expect that the technology won't move there."

Hunter acknowledges that the Physiome Project is a long way from fulfilling its potential. It needs more complexity on the molecular level before it can simulate all the effects of an experimental drug or a surgical procedure. "The biggest challenge," he says, "is being able to understand gene regulation." And certain parts of the human body - the brain, the immune system - are still very much a mystery. But after all, that's what computers and Erector sets are for.