ericsphotography/Getty Images

To get an up-close look at a patient's tissue

, a doctor typically does a biopsy—chops off a tiny chunk of organ or tumor and sends it to a lab for processing. The lab encases the tissue in paraffin wax, then shaves it into slices thin enough to be analyzed on a microscope. The process takes a living, three-dimensional tissue and turns it into a frozen 2D image, like a snapshot of an action scene.

According to an article in this week's Nature, implantable microscopes are allowing doctors and scientists to study living-cell interactions from inside the body in real time. The new imaging techniques may reduce painful biopsies for patients. And having a better understanding of how cells behave in their natural environments could help scientists to develop more effective treatments.

Medical imaging pioneer Christopher Contag from Stanford University thinks implantable microscopes will one day enable scientists to quickly diagnose disease from inside the body. He got involved with implantable microscopes after trying to figure out how HIV gets passed from mothers to babies. "I thought, ‚ÄòThis would be so much easier if we could actually watch the cells move around in the body,'" Contag says.

Previous attempts to watch living-cell interactions involved making an incision, pinning back the skin, and studying tissue through a standard confocal microscope. That's the method Zena Werb from the University of California at San Francisco has used to study the movement of cells within a tumor in anesthetized rats. But that technique has about a 6-hour time limit attached to avoid harm to the animal, and of course, those studies couldn't be done in humans.

"Our idea is, rather than putting the mouse on the stage of a microscope, let's put the microscope in the body and image the tumor over time," Contag says.

Contag's group has built an implantable microscope that will monitor interactions between immune cells and tumors for days or weeks at a time. The mini microscope is shaped like a cylinder and measures 3 mm by 5 mm. It is made of aluminum-coated silicon wafers, and can image at a resolution of 0.1 micrometers. The group recently began testing the mini microscope in rats and mice.

Although the researchers hope to make the device inexpensive and disposable, it currently relies on lasers that can cost as much as $10,000 apiece. Another challenge is that powering the microscope and retrieving the images requires running a wire through the animal's skin, which can put the animal at risk for infection and can generate scar tissue that interferes with imaging capability. Several research groups are currently working on creating untethered implantable devices that could send out images wirelessly.

The field of in vivo microscopy is still young, but it has already helped scientists to better understand how cells move through the body and interact with other cells. One study by immunologist Philippe Bousso used multiphoton microscopy to evaluate a treatment that removes T cells from the body, teaches them to attack a tumor, then injects them back into the body. By watching as the immune cells fought the cancer cells in a living animal, Bousso observed that T cells move much more slowly inside an organism than they do in a petri dish. To make the therapy work, he suggested using a higher dose of the trained T cells.

Contag says that in the short term, implantable microscopes will guide doctors to take better biopsies. "Right now, biopsies are taken with very little information," Contag says. "The clinician says, ‚ÄòThat looks strange, I think I'll take a sample for that.'"

Changing the way doctors make diagnoses, however, could take much longer. "Replacing biopsy procedures could take several years," Contag says. "It requires a paradigm shift in the way we make a diagnosis and the way we treat patients."

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io