Science finding ways to regrow fingers

New York, Feb 19: Researchers are trying to find ways to regrow fingers — and someday, even limbs — with tricks that sound like magic spells from a Harry Potter novel.

There's the guy who sliced off a fingertip but grew it back, after he treated the wound with an extract of pig bladder. And the scientists who grow extra arms on salamanders. And the laboratory mice with the eerie ability to heal themselves.

This summer, scientists are planning to see whether the powdered pig extract can help injured soldiers regrow parts of their fingers. And a large federally funded project is trying to unlock the secrets of how some animals regrow body parts so well, with hopes of applying the the lessons to humans.

The implications for regrowing fingers go beyond the cosmetic. People who are missing all or most of their fingers, as from an explosion or a fire, often can't pick things up, brush their teeth or button a button. If they could grow even a small stub, it could make a huge difference in their lives.

And the lessons learned from studying regrowth of fingers and limbs could aid the larger field of regenerative medicine, perhaps someday helping people replace damaged parts of their hearts and spinal cords, and heal wounds and burns with new skin instead of scar.

But that's in the future. For now, consider the situation of Lee Spievack, a hobby-store salesman in Cincinnati, as he regarded his severed right middle finger one evening in August 2005.

He had been helping a customer with an engine on a model airplane behind the shop. He knew the motor was risky because it required somebody to turn the prop backwards to make it run the right way.

He'd misjudged the distance to the spinning plastic prop. It sliced off his fingertip, leaving just a bit of the nail bed. The missing piece, three-eighths of an inch long, was never found.

An emergency room doctor wrapped up the rest of his finger and sent him to a hand surgeon, who recommended a skin graft to cover what was left of his finger. What was gone, it appeared, was gone forever.

If Spievack, now 68, had been a toddler, things might have been different. Up to about age 2, people can consistently regrow fingertips, says Dr. Stephen Badylak, a regeneration expert at the University of Pittsburgh. But that's rare in adults, he said.

Spievack, however, did have a major advantage — a brother, Alan, a former Harvard surgeon who'd founded a company called ACell Inc., that makes an extract of pig bladder for promoting healing and tissue regeneration.

It helps horses regrow ligaments, for example, and the federal government has given clearance to market it for use in people. Similar formulations have been used in many people to do things like treat ulcers and other wounds and help make cartilage.

The summer before Lee Spievack's accident, Dr. Alan Spievack had used it on a neighbor who'd cut his fingertip off on a tablesaw. The man's fingertip grew back over four to six weeks, Alan Spievack said.

Lee Spievack took his brother's advice to forget about a skin graft and try the pig powder.

Soon a shipment of the stuff arrived and Lee Spievack started applying it every two days. Within four weeks his finger had regained its original length, he says, and in four months "it looked like my normal finger."

Spievack said it's a little hard, as if calloused, and there's a slight scar on the end. The nail continues to grow at twice the speed of his other nails.

None of this proves the powder was responsible. But those outcomes have helped inspire an effort to try the powder this summer at Fort Sam Houston in San Antonio, on soldiers who have far more disabling finger loss because of burns.

Fingers are particularly vulnerable to burns because they are small and their skin is thin, says David Baer, a wound specialist at the base who's working on the federally funded project. The five to 10 patients in the project will be chosen because they have major losses in all their fingers and thumbs, preventing them from performing the pinching motion they need to hold a toothbrush, for example.

The soldiers will have the end of a finger stub re-opened surgically, with the powder applied three times a week.

Nobody is talking about regrowing an entire finger. The hope is to grow enough of a finger, maybe even less than an inch, to do pinching.

And it is just a hope.

Source:ZeeNews