There are some fancy tools out there for repairing skin, from 3D bioprinting, scaffolds and matrices to spray guns that rain stem cells directly onto a wound. Doctors in Brazil are even experimenting with sterilized Tilapia fish skin as a novel dressing for burns.
Creativity is nice, but that alone won’t save patients battling through the most critical hours of their lives. Denver Lough, an M.D./Ph.D., saw this first hand while working at the Johns Hopkins Plastic and Reconstructive Surgery Program. Nothing was truly getting the job done.
“Name one regenerative medicine product or company that’s out there that actually truly regenerates anything,” Lough challenged in a recent phone interview. “Not, ‘we grow keratinocytes,’ or ‘we can turn a cell into an osteogenic lineage’ but really; does this grow full thickness tissue? There’s really not one out there and there’s certainly not one that’s being used clinically right now for skin regeneration.”
Now CEO and CSO of PolarityTE, Lough believes the fundamental approach to tissue regeneration is taught wrong. And that’s why, after all these years, skin healing remains imperfect.
Biotechs working in this field have zoomed in on individual cells, he said, working to culture and manipulate stem cells or to find the right recipe for growth factors that can guide differentiation. That’s not how biology works, Lough contests.
“[Biology] works through cells interacting with each other, having gradients, having interfaces, having polarity. A cell needs to know what way is up, what way is down,” he said. “When you pull a single cell out of a tissue and try to command it to go down a pathway, you negate all of those factors.”
The cells need to know what pathways their neighbors are expressing.
Put another way: “It’s like taking you in the middle of the night, out of your bed, taking off your clothes, cutting off parts of your arms and legs, pushing you through a screen door and throwing you out in the middle of the ocean and saying act like you, conduct yourself like you,” Lough said earnestly.
PolarityTE will relocate you, your family, and your house. Its first product, for skin regeneration, starts with just a small piece of healthy skin taken from a patient with extensive burns. The sample is shipped to the company’s facility in Salt Lake City, Utah, where it is processed into a paste to cover the wound. The paste contains so-called Minimally Polarized Functional Units (MPFUs) that instinctively organize and propagate to help heal a wound. The turnaround time is just 24-48 hours and the use of the patient’s own tissue obviates the risk of immune rejection.
With this new take on an old skin graft approach, PolarityTE aims to capture the diversity of the tissue ecosystem, with epidermal, dermal, and hypodermal cells, fibroblasts, hair follicles — even the structural organization and blood vessel integration seen in the natural skin.
Of note, the technology pays special attention to the edges of the wound where the real healing occurs, “it’s not a single cell that jumps between the margins,” Lough said.
It’s still early days, but the company recently announced the successful grafting of “regenerated full-thickness, organized skin and hair follicles in third-degree burn wounds” in pigs. The team is now looking ahead to a first-in-human trial in the third-quarter of 2017.
It would be a mistake, however, to place PolarityTE in the bucket of skin grafts only. Lough hopes the technology can go much further, to regenerate and restore bone, muscle, fascia, cartilage, and nerve tissues.
Photo: VolodymyrV, Getty Images