Science in the Triangle

Efforts to grow skin, organs and blood vessels have advanced so fast so far that researchers who gathered Tuesday at the regenerative medicine forum in Winston-Salem paused before offering suggestions what they might accomplish in the next two decades.

Fashioned after conferences that have sprung up in the past few years across the U.S. and in Europe, the three-day forum brought together researchers, investors and policymakers interested in regenerative medicine, tissue engineering and stem cells. It was the first such event organized by Wake Forest University’s Institute for Regenerative Medicine, which is headed by Dr. Anthony Atala, a urological surgeon who in 1999 was the first to implant a laboratory-grown organ into a patient.

Dr. Robert Lanza

The organ was a bladder. Now researchers are working on skin, blood vessels and entire livers. So, what’s next? How about a whole heart, or a kidney grown from a skin cell?

“I don’t think that’s science fiction,” said Dr. Robert Lanza, chief scientific officer of Advanced Cell Technology, a biotech company near Boston.

Buddy Ratner

Buddy Ratner, professor of chemical engineering and bioengineering at the University of Washington in Seattle, agreed. “In the next 10 years, regenerative medicine will revolutionize medicine,” Ratner said.

“The future will be ours to grab,” said Tim Bertram, but the Tengion executive added, “If the public isn’t demanding it, [development] will slow down.”

Tim Bertram

Lanza, Ratner and Bertram made the comments answering questions from science, health care and medical writers who attended the forum. Bertram’s words of caution reflected the difficulties some regenerative medicine companies faced after the recession dampened investors’ willingness to fund brave-new-world-type technologies.

Advanced Cell Technology has battled fund-raising problems for two years and its stock trades for pennies a share. Tengion, which is trying to bring some of Atala’s technologies to market, ran into regulatory hurdles and had to cut jobs last year. The Pennsylvania-based company, which has research and development operations in Winston-Salem, plans to raise up to $44 million in an initial public offering this week, according to Renaissance Capital.

Regenerative medicine takes a lot of inspiration from old-fashioned surgery. But where surgery tries to repair, regenerative medicine aims to replace or augment. The spare parts are built outside the body, with the patient’s own cells or with different types of stem cells.

Artificial materials play an important role in shaping the spare parts. So do different techniques to construct them.

Scaffold to grow an ear in a dish.

At Wake Forest’s Institute of Regenerative Medicine, researchers use scaffolds made from porous materials and seed them with cells to grow ears for soldiers who suffered head injuries. The same scaffolds can also be used to fashion toes or fingers. To make heart valves, pieces of blood vessel or skin, the researchers may use a three-dimensional printer whose cartridges are filled with cells and a gel instead of ink.

Kyle Binder, a doctoral student at the institute who pursues degrees to practice medicine and do research, is working on a mobile bioprinter that would allow doctors to print cells directly onto burn wounds or open wounds from foot ulcers, a complication from diabetes, and allow for new skin to grow without scarring.

The bioprinter is equipped with a laser scanner to map the wound, Binder said. Then, clusters of 10 to 500 cells are deposited rapidly across the wound layer after layer. The bioprinter can cover the upper front body of an adult in as little as half an hour and animal tests have shown that the wound heals in about two weeks, he said.

Dr. Anthony Atala

Researchers in regenerative medicine have been able to grow muscle, bone, cartilage and retinas and they’re working on lungs and kidneys, said Atala, who also spoke at the forum. All of these spare parts can be made from a patient’s own cells, which would eliminate drugs to block the body from rejecting transplants.

Nerve, liver, pancreatic and heart muscle cells are the only ones that researchers have not yet been able to coax into growing in the lab, Atala said. Different types of stem cells are used instead.

Researchers are also experimenting with manmade materials. Healionics, a spinoff of the University of Washington, is working with material that has long been used to make soft contact lenses. The material has tiny pores, which promote blood vessel growth and healing. Small pieces of the material have been used to regenerate skin and bone and tests are under way to use it as a heart muscle patch, said Ratner, who was instrumental in developing the technology.

Regenerative medicine promises to help patients waiting for organ transplants and to reduce the need for some costly medical procedures, such as kidney dialysis. Diseases that could be treated with regenerative medicine cost the U.S. health care system about $400 billion in 2004, Atala said.

But the health care insurance system will ultimately determine which spare parts will become available in the next 10 years, said Richard Caruso, founder of Integra, a New Jersey regenerative medicine company that develops and markets surgical implants and medical devices. Technologies for which insurance companies are willing to pay are the most likely to get developed.