In what could be a major step forward for regenerative medicine, scientists in Sweden have given a cancer patient a new organ grown from his own cells.
Scientists at the Karolinska Institute in Sweden gave Andemariam Beyene a new windpipe —made of plastic and Beyene's own cells— to replace the one destroyed by cancer.
A report on The New York Times said Beyene had almost lost hope in 2011 about a golf ball-sized tumor growing into his windpipe that had defied surgery and radiation.
But his doctor, Paolo Macchiarini, fashioned a new windpipe for Beyene using plastic and his own cells.
“The human body is so beautiful, I’m convinced we must use it in the most proper way,” said Macchiarini, a surgeon who runs a laboratory that is a leader in the field, also called tissue engineering.
In Beyene’s case, doctors made a copy of his windpipe using a porous, fibrous plastic, and seeded it with stem cells harvested from his bone marrow.
The implant was then bathed in a nutrient solution in a bioreactor for a day and a half, then stitched into Beyene.
Some 15 months after the operation, Beyene, 39, who hails from Eritrea, is tumor-free and breathing normally. He is back in Iceland with his wife and two small children.
“Over 27 years, I’ve become more convinced that this is doable,” added Dr. Joseph Vacanti, a director of the Laboratory for Tissue Engineering and Organ Fabrication at Massachusetts General Hospital and a pioneer in the field.
Other organs
The NYT report said similar techniques are being used to build more complex organs - such as kidneys and livers at Wake Forest University in North Carolina.
Labs in China and the Netherlands are among many working on blood vessels, it added.
On the other hand, Macchiarini wants to go further, using the body’s repair mechanisms to remake a damaged organ on its own.
Along with new advances in knowledge of stem cells, scientists are learning more about scaffolds, compounds that hold cells in place - and play a key role in how cells are harnessed to repair damaged tissue.
But tissue engineers said their work at this time is still experimental, though the possibilities seem promising.
Specialized cells
The NYT report said a normal windpipe is lined with specialized cells, including some that produce mucus to trap particles - with coughing bringing out the mucus.
In Beyene's case, Macchiarini counted on stem cells to differentiate into these other kinds of cells, generating a lining for the windpipe.
Beyene’s doctors also tested if his windpipe was developing a blood vessel network - by deliberately injuring the internal lining slightly to see if it bleeds.
“If it bleeds, it lives,” Macchiarini said. The windpipe passed the test.
No need for anti-rejection drugs
As Beyene’s new windpipe has only his own cells, he does not need to take drugs to suppress his immune system to prevent rejection.
Still, the synthetic scaffold is a foreign material that caused his body to produce scar tissue, which had to be removed.
Bioartificial windipie
In November 2011, five months after Beyene’s surgery, Macchiarini implanted a bioartificial windpipe in another cancer patient, Christopher Lyles.
This time, he used an improved plastic scaffold made of even smaller fibers for the cells to be embedded in.
But Lyles died in March, with his family not disclosing the cause of death. Still, Macchiarini said the implant had been functioning well.
In June, Macchiarini performed similar operations on two patients in Russia. He said both are doing well.
But while Macchiarini is planning more operations he admitted there needs to be a less complex and cumbersome solution, noting procedures can take up half a million dollars.
Ultimate dream
The NYT report said his ultimate dream is to eliminate even the synthetic scaffold, and to allow the body to rebuild its own scaffold instead.
“Don’t touch the patient. Just use his body to recreate his own organ. It would be fantastic,” he said. — TJD, GMA News
