A paralyzed Polish man is walking again following a pioneering procedure in which cells taken from his nasal cavity were transplanted into his injured spinal cord, doctors report.

Darek Fidyka, paralyzed from the chest down after a 2010 knife attack, is able to walk with a support frame, say Polish surgeons who carried out the treatment in collaboration with British scientists.

Fidyka, a firefighter, suffered multiple stab wounds in the attack, one of which cut almost all the way through his spine.

It was this wound that was filled with specialized cells called olfactory ensheathing cells taken from his own nasal cavity.

The cells can serve as guideways for the growth of new neurons, the researchers said.

"This guidance property of OECs led to the suggestion that isolation and transplantation of these cells could promote axonal regeneration in the injured spinal cord," authors of a 2008 study on such cells wrote.

Already demonstrated in rodent studies, the procedure on Fidyka is evidence of its effectiveness in humans, the researchers say.

Geoff Raisman of the Institute of Neurology at University College London, who led the British research team, called the result "more impressive than man walking on the moon."

"[Fidyka] can get around with a walker and he's been able to resume much of his original life, including driving a car," Raisman said. "He's not dancing, but he's absolutely delighted."

Surgeons first removed OEC cells from Fidyka's nasal cavity, then grew them in culture.

After two weeks the cells were transplanted into Fidyka's spinal cord, as doctors injected them above and below the spinal injury.

That allowed nerve fibers on either side of the injury to reconnect over a pathway created by the ensheathing cells, doctors said.

Before the procedure Fidyka had displayed no signs of recovery in spite of months of intensive physiotherapy.

Two years on from the procedure, he can walk using a support frame. While he tires easily, the 38-year-old says he expects to continue to make progress.

"I think it's realistic that one day I will become independent," he says.

The result can give hope to many people whose paralysis has been considered untreatable, says neurosurgeon Dr. Pawel Tabakow of  Wroclaw University Hospital, who headed the Polish research team and is lead author on the published study describing the procedure.

"It's amazing to see how regeneration of the spinal cord, something that was thought impossible for many years, is becoming a reality," he says.

Spinal cord injuries are suffered by more than 11,000 annually in the United States alone, the 2008 study said.