The Body Shop Science Is Busy Producing New Organs For Animals, Using Their Own Cells For Regeneration, And The Promise For Human Spare Parts, Especially For Correcting Birth Defects, Is Exciting.

Scientists have grown replacement organs for sheep, rats and rabbits using the animals’ own cells and lab molds to help the tissue take shape - a technique that could be used someday to make spare parts for people.

While scientists have already found ways to grow skin and cartilage, two Harvard researchers claim to be the first to have grown animal tissue from a variety of organs, including the heart, kidneys and bladder.

“As surgeons, that’s what we dream about - having a shelf full of body parts,” said Dr. Anthony Atala, who pioneered the technique with Dario Fauza.

Their new method - to be presented Wednesday at a conference of the British Association of Pediatric Surgeons in Istanbul, Turkey - has already been used to build new bladders and windpipes for sheep, a kidney for a rat and leg muscles for a rabbit.

The organs - built with tissue taken from both grown and fetal animals - were transplanted into those creatures and have worked just fine so far, the researchers said.

The two doctors said the greatest hope for the technique could be in correcting common birth defects. They have developed a method for growing replacement organs for newborns while they are still in the womb.

For example, if a fetus has a malformed trachea, surgeons could extract some of those cells from the womb, grow the new windpipe in the lab and have it ready to be transplanted when the baby is born.

“This can save lives,” Fauza said.

Tests on humans, in the womb and out, are set to begin within a year, and the researchers hope to get approval from the Food and Drug Administration for routine use within five years.

Cornell University researcher Thomas McDonald, who studies the development of sheep fetuses, said the method appears to be a way around the biggest obstacle to organ transplants - the body’s rejection of foreign parts.

Normally, surgeons have been forced to use mismatched tissues to repair defects, like a piece of intestine to patch a hole in the bladder.

“It sounds like a wonderful technique, and it sounds very doable,” McDonald said. “It’s just that nobody has tried it until now.”

The procedure is tricky and requires balancing delicate laboratory work with microscopic surgery inside the womb. Doctors first detect birth defects using ultrasound, as early as 3-1/2 months into pregnancy.

They operate on the fetus two-thirds of the way through pregnancy. Through small incisions, they lower a surgical camera and long, narrow instruments into the womb. Guided by a large video monitor, they remove a pea-size sample of the defective organ. Drugs are used to prevent the mother from going into labor.

Then it’s on to the laboratory.

Under ventilation hoods, lab technicians separate different types of cells and place them in dishes of a clear solution rich in proteins and nutrients.

With the solution - which is the key to the process - the tissue can grow in an incubator at an astounding rate. A sample the size of a square centimeter could produce enough tissue within two months to cover two football fields.

Next, Atala and Fauza build the organ by draping fragile tissue over biodegradable scaffolds.

In the case of a sheep’s bladder, it was fashioned by layering epithelial cells on the inside of a cup-shaped structure and muscle cells on the outside. Atala said the bladder cells know which way to orient themselves to each other and grow until they fill out the scaffold.

Within six weeks of surgery, the new bladder is ready. It was transplanted in the newborn sheep and functions as it should.

The researchers also hope to grow organ tissue for older people.

Five-year-old Renato Sehovic is one such candidate. Born in Bosnia, he suffers from a severe defect called bladder extrophy, which left his bladder underdeveloped and sticking out of his abdomen.

“The minute he was born, the doctor said there was nothing she could do for him,” said Renato’s mother, Nada.

Now there’s hope the boy’s bladder can be repaired with his own tissue.

“When you look at organ shortages today and all the problems we experience with children and adults who end up dying before they get one, wouldn’t it be nice to have a repository of tissue you can access?” Atala said.