![]() |
|
October 2004
TR 100 Biotech and Medicine
Researchers are tearing down the wall between the life sciences and information technology
By Erika Jonietz
Biologists and physicians are notorious for cyberphobia, but this year's TR100 honorees in biotechnology and medicine are erasing that stereotype -- and the boundaries between the life sciences and information technology along with it. Many are pioneering fields intimately connected with or influenced by computing, areas as diverse as bioinformatics and brain-computer interfaces. Some of the most exciting advances are happening in electronic health care, synthetic biology, and ultrasensitive diagnostics. With the addition of computers, "I see the whole medical process being very different -- much less haphazard, much more rational," says Colin Hill, founder of Gene Network Sciences, which uses computer models of cells to predict how well potential drugs will work. "Ultimately, I see this future world of medicine where doctors can measure molecular activity in the body, feed it into a computer model, and determine the right treatment for the person." Even before that day arrives, mobile computing will change the nature of medical practice, says Vikram Kumar, a resident at Boston's Brigham and Women's Hospital. He believes that simple, portable computer programs can encourage people to adhere to treatment regimens -- one of the biggest challenges in medicine today. As a medical student, Kumar started a company called Dimagi to develop such tools. One example is a PDA-based game that helps diabetic kids understand how their behavior affects their blood-glucose levels. Kumar hopes that one day his management systems, combined with cheap, at-home diagnostic tests that give patients up-to-the-minute data on their physical conditions, will keep people with chronic ailments from landing in the hospital. "The biggest dream I have is that one day we can close all the hospitals," he says. Lauren Meyers could help him empty them out, first. By modeling how people interact in schools, hospitals, and other settings, the University of Texas at Austin mathematician can make detailed predictions about how a disease will spread. She can also use those models to determine which interventions -- vaccinating health-care workers or closing schools, for example -- will most effectively halt an outbreak. The British Columbia Centre for Disease Control has enlisted her help to create control strategies for future outbreaks of SARS: her models have shown that using masks in hospitals, for instance, should be as effective as more drastic measures such as closing schools. While researchers like Meyers and Kumar are using computers in a literal sense, others are using ideas borrowed from computing to understand and even "program" living cells. In this new field of synthetic biology, "we're taking existing, well-characterized genes and putting them together in new combinations so that we get interesting behaviors," says Caltech biophysicist Michael Elowitz. Synthetic biologists call these new gene combinations "genetic circuits," because they provide a means of rewiring, or programming, a cell's behavior. Ultimately, these researchers hope to program cells to perform crucial tasks. Boston University bioengineer Tim Gardner, for instance, wants to program bacteria to develop new antibiotics, clean up the environment, or generate electricity. In each case, he's mapping the genetic pathways that control bacterial metabolism and then trying to manipulate them -- to, say, turn toxins into harmless compounds. Even in cutting-edge medical diagnostics, there are parallels to computing. Electrical engineers have found light to be the nearly perfect medium for transferring data quickly and precisely; similarly, biomedical engineers are using light to obtain information about the body on a finer scale than ever before possible -- so that they can detect diseases much earlier and with greater sensitivity. "The sooner you detect, the better," says Vadim Backman, a bioengineer at Northwestern University. Many cancers are curable if doctors detect them early enough, and Backman aims to make sure they do. With his technique, a doctor simply shines light on biological tissue. By collecting and analyzing data about light's wavelength, direction, and polarization as it bounces off different tissues, Backman has developed "fingerprints" of the minute structural changes in cancerous cells. This sensitivity has allowed him to detect colon cancer in rats earlier than with any other method; human tests have already begun. By inserting a probe only 1.5 millimeters wide just a few centimeters into a patient's rectum, a doctor should be able to predict whether the patient has precancers in any part of the colon. Backman hopes this will provide a cheap, quick, and easy screen for colorectal cancer. Vasilis Ntziachristos at Harvard Medical School has similar goals. He has developed the hardware and software needed to produce 3-D images that reveal the locations of telltale molecules, such as cancer-related proteins, deep inside the body. Monitoring such molecules could allow physicians to make earlier and more precise diagnoses than they can by examining the anatomical features detected by imaging techniques such as CT and MRI scans. Today, the technology, which is similar to a CT scan but uses fluorescent tags and beams of infrared and visible light instead of radioactive dyes and x-rays, is used to observe molecules at work in living animals, helping researchers decipher how cells normally function and what goes wrong in disease. Within a few years, doctors may be able to use such molecular-imaging tools to detect tumors smaller than one millimeter in size. These researchers don't think small, and some of their goals may take decades to reach. Yet within our lifetimes, says Kumar, electronic health care, synthetic biology, ultrasensitive diagnostics, and other technologies will combine to create a whole new way of practicing medicine, allowing doctors to personalize treatments and even prevent illnesses before they strike. Hill agrees. "It's going to be profound, more so than a lot of the discoveries that happened in the physical sciences and computing sciences," he says. "Science is finally about life now; it's finally about us."
Biotech Profiles Yaakov Benenson In just five years, Benenson has taken the concept from drawing board to test-tube prototype. Working at the Weizmann Institute of Science in Rehovot, Israel, he has built molecular devices -- essentially DNA strands and enzymes -- able to analyze genetic changes associated with lung and prostate cancers and to release a drug in response. These prototypes are "a beautiful work of molecular and conceptual integration, pointing the way toward truly integrating diagnostics with therapeutics," says George Church, director of the Center for Computational Genetics at Harvard Medical School. "Using these tiny diagnostic machines, we could selectively treat only the diseased cells," Benenson says. For example, the prototype device for small-cell lung cancer assesses the activity of four genes. Cancerous cells produce extra RNA copies of each of these genes. Consecutive sections of the DNA strand in the prototype bind, in turn, to these RNA strands; when they do, an enzyme chops them off. If all of the cuts are made properly, the enzyme releases and activates an anticancer drug that has been tethered to the DNA in an inactive form. Benenson's molecular machines offer a unique combination of precision and flexibility. A single one of them can be designed to look for up to 10 different diagnostic markers before it releases its drug payload. The devices can also be tailored to several different diseases through simple-to-make changes in their DNA sequences. These machines represent a quantum leap not only in medicine but also in DNA computing. Benenson's molecular "doctors" -- which are computers in the sense that they store information and analyze it following a yes/no logic -- are "directed at a practical interface with biomedicine rather than losing an abstract race with existing computers on their own turf," says Church. It will be a while before molecular machines replace existing systems of diagnosis and treatment: Benenson estimates three or four years before even simple versions that work in a living cell are ready, and perhaps decades before they can be tried in people. If the DNA doctors prove as successful in the body as they have in the lab, though, they might spark a revolution in medicine. Colin Hill Smruti Vidwans Xiaowei Zhuang Zhuang accomplished this feat by attaching fluorescent molecular tags to the virus; when excited with a laser, the tags emit specific colors of light. She has used the approach to track the behavior of not only individual viruses but even individual molecules, such as strands of RNA, at unprecedented levels of detail. Coming from a traditional physics PhD program, Zhuang very quickly began to lead experiments in single-molecule biophysics as a postdoc in Steven Chu's lab at Stanford University. "With total ease, she immersed herself in biological physics and did an astounding amount of seminal work," Chu says. Since establishing her own lab at Harvard, Zhuang has continued to do "landmark experiments at a blistering pace," he adds. Direct observations of individual molecules are essential to really understanding how life works, Zhuang believes. "In the biology world, there are a lot of very small things that are doing critical functions," she says. "There is a lot of interesting dynamic information one can get out of this kind of single-particle approach." In her work on the flu virus, for example, Zhuang discovered that viruses move through the cell in three stages -- one of which is so short that it could only be directly observed with high-speed imaging. "This experiment revealed unprecedented details of virus infection pathways," says Harvard chemist Sunney Xie. Eventually, this in-depth understanding of how viruses work will help researchers find entirely new ways of blocking viral infection, Zhuang says. Indeed, virologists have begun asking to work with Zhuang, hoping to use her methods to study their own pet viruses. Vadim Backman Selena Chan Rebekah Drezek Ryan Egeland Michael Elowitz Tim Gardner Shana Kelley Gloria Kolb Vikram Sheel Kumar Jörg Lahann Eric C. Leuthardt David Liu Frank Lyko Lauren Meyers Ananth Natarajan Vasilis Ntziachristos Shayn Peirce Sandra Waugh Ruggles Christoph Schaffrath Monisha Scott Christina Smolke Kahp-Yang Suh Olga Troyanskaya Lei Wang Copyright Technology Review 2004. Upcoming Events
BIO International Convention | |||||||||||||||||||||||||||||||||