Skin-cell gun expedites burn victim recovery time

The latest technology in burn-victim treatment looks like it belongs in a society of robots and… The latest technology in burn-victim treatment looks like it belongs in a society of robots and flying cars — it’s a gun that sprays regenerated skin cells onto damaged skin.

Dr. Jörg Gerlach of Pitt’s McGowan Institute for Regenerative Medicine developed a skin-cell gun after eight years of research.

“As a surgeon, I was looking for areas where I could apply my knowledge in cell-based therapy development,” he said.

The skin gun resembles an airbrush gun, except the tube feeding the gun does not attach to a container of compressed air. Instead it attaches to a large metal box — part of an electronically processor-controlled pneumatic device that sets Gerlach’s skin gun apart from others.

“Skin-cell spraying is not new. It was invented around 20 years ago in Argentina, and it is also performed in Australia, but with a hand pump atomizer similar to these window cleaning sprayers,” he said.

But Gerlach said that, unlike the hand pump, his electronic processor “does not injure the cells during spraying.”

To begin the skin spray process, surgeons use a dermatome, a special knife that cuts only a thin layer of the donor area of the patient’s healthy skin, Gerlach said.

The removed skin cells and the skin stem cells are isolated in an aqueous solution for 90 minutes. The mixture is loaded into syringes and inserted into the nozzle of the gun. From the gun, the cells are sprayed directly onto the wound.

Dr. Alain Corcos, trauma director at UPMC Mercy, is part of Gerlach’s skin gun team. He finds patients for Gerlach to treat and has used the gun before. So far, four burn patients have been treated at Mercy. He said he couldn’t discuss the outcome of those cases.

When burn patients are treated with the gun, it feels like they “are just getting saline sprayed onto their arm,” he said.

“The gun is used to distribute it in a uniform way, at a uniform velocity,” Corcos said. “The liquid is clear, you can’t see skin cells with the naked eye.”

Gerlach said the entire process takes two hours, and recovery to close the wound takes about a week.

“It then takes several months for regeneration of the color and skin texture,” he said.

Currently, the skin gun can only treat deep dermal wounds, which are severe second-degree burns. Gerlach said that he and his team are working on addressing third-degree burns.

Deep dermal wounds burn through the top layer of skin, the epidermis, and deep into the second layer, the dermis. The burns result in red-and-white bloody blisters. Burns that extend all the way through the dermis are classified as third-degree burns.

Corcos said that this specific burn type leaves a “very small subset of patient.”

Most burns that are superficial will heal on their own, and burns that are very deep will need a traditional skin graft, Corcos said. Deep dermal wounds lie between these two extremes.

Traditionally doctors would let this subset of burns heal on its own, but Corcos said the healing process takes a long time, often more than two weeks. The skin gun cuts the healing time.

Gerlach said using the skin gun treatment results in less scarring than allowing the burns to heal on their own.

Dr. William Hughes, medical director at Temple University Hospital’s Burn Center, , said that he had watched a video on the skin gun but other than that did not have much knowledge on the subject.

Hughes said that to treat a burn, the dead skin needs to be removed so that the layer underneath can get nutrients.

“Yeah, maybe [the skin gun] would work,” Hughes said. “But I think there would still need to be a prepared bed. You can’t throw seeds on concrete, you need soil.”

Hughes said Temple’s Burn Centercurrently treats second-degree burns according to severity.

Localized second-degree burns often take between 10 days and two weeks to heal on their own, and ointments and antibiotics are prescribed.

Biosynthetics, such as pig-skin xenografts, are used for more-severe second-degree burns.

“It adheres to the wound and stays there,” Hughes said. “As it heals it lifts up.”

Biobrane, a synthetic, silicone dressing, is another form of treatment.

“There are complications,” Hughes said. “There is always a small chance for infection since it takes a longer time to heal.”

Skin grafts are used in third-degree burns in which both layers of skin are destroyed and the burn goes into the fat tissue. The procedure leaves a “poor-looking scar,” he said.

The skin gun is currently in phase-I, early prototype stage, Gerlach said. It still has to go through phase II and III of clinical studies before it is out of the experimentation stage — a process he estimates will take about four years.

Gerlach said he would like to start a larger study with the Department of Defense-sponsored Armed Forces Institute of Regenerated Medicine initiative.

Dr. Ben Harrison, with the Wake Forest-Pittsburgh AFIRM consortium, said he is optimistic that Gerlach is doing “great science.”

“Dr. Gerlach’s work is seen as one of the next generation of cell delivery technologies, and this is one of the more visible projects within our Burn Program,” Harrison said. “Currently, there are no AFIRM-supported studies using his technology beyond the original scope of work.”

In the future, Gerlach sees the skin gun being used as therapy for acute burns in burn centers.

“It is great to see [our] own developments in the clinical setting,” he said. “But of course we are a larger team that also includes Dr. Corcos at UPMC Mercy Hospital and the credit should go to the entire team.”