Breakthrough started the discussion: what do we make now? One faction wanted to go big, but the one that wanted to try their hand won. They envisioned his five-fingered structure that could be cut open on the wrist, slipped on like a glove, and sutured. “You just need to put a bandage around your wrist, and that’s the surgery,” he said.
So the lab printed a five-fingered scaffold roughly the size of a sugar packet, prepared the cells as before, and then measured how much more “rimless” structures were compared to conventional grafts. Tested to see if it holds up. Edgeless structures outperform flat patches by up to 400% in mechanical strain tests. Microscopic images revealed a healthy, more normal extracellular matrix, the network of proteins and molecules that provide structure to tissues. This matrix had more molecules such as hyaluronic acid and a more realistic cell layout. Mr. Abaci was delighted, but he was surprised. nothing else. He believes this method is suitable for creating a more normal alternative skin because the cells can grow in a way that is naturally enclosed.
But is such a skin graft really possible? tookPappalardo’s mouse demonstration (which he ended up doing 11 times) suggests that. I couldn’t do the same surgery with a flat graft. He decided to try mouse hindlimbs because the shape of the region is so complex. After 4 weeks, the skin replacement was fully integrated into the surrounding skin of the mice.
Adam Feinberg, a biomedical engineer at Carnegie Mellon University, said: “We are on the road to making these technologies more widely available. Ultimately, he said, in another decade or so, the way the human body repairs itself after injury or illness will change dramatically.” prize.”
He’s particularly excited about how they can bring new blood vessels to the skin and help blood vessels grow. “Angiogenesis is what keeps tissue alive,” says Feinberg. One of the reasons people get diabetic ulcers in the first place, he said, is poor blood circulation to the tissues. “If [engineers] If we can improve the vascular quality of the tissue, we may have more success,” he says.
Instead of transplanting large amounts of tissue from elsewhere in the patient’s body, these structures could be grown from very small biopsies, said Johns Hopkins University plastic surgeon and tissue engineer Sashank Reddy. I point out that you can. “Let’s say you had to resurface someone’s entire forearm, and it had a lot of skin that had to be borrowed from elsewhere on the body, like the back or thigh,” he says Reddy. Removing that tissue creates a defect in the “donor site” from which it was taken. “Another advantage of this approach is that it avoids defects in the donor site, not just geometry,” he continues.
Sherman also said a one-hour transplant is a vast improvement over today’s transplant surgeries, which take between four and 11 hours and require extensive anesthesia for vulnerable patients. “This could be a big step forward,” he says Sherman.
Video: Alberto Pappalardo/Abaci Lab
Still, Reddy says the new structure has to clear some hurdles, including clinical trials, before it can be used by surgeons. Not many companies have tried to implant artificial tissue into patients. Last year, something called 3DBio implanted a human ear printed out of cells.
Reddy points out that this tissue lacks some components of real skin, such as hair follicles and sweat glands. “People can think of these as ‘nice to have,’ but they are very important in fixing the skin,” he says. is important. However, he is optimistic that these add-ons are feasible, and says that surgical demonstrations in mice are easier to apply to humans than drug trials conducted in mice. There are always surprises in science, and it’s safe to say that they are recreated,” he says. “This is more of an engineering problem than a fundamental discovery problem.”
Abaci believes this artificial skin could potentially be used to test pharmaceuticals and cosmetics, as well as to study the basic biology of skin. But his main attraction is creating transplants. Ideally, an implant that could be used as a single wearable piece and could be designed with the help of other research groups specializing in muscle, cartilage or fat.
In the meantime, his group has been working on creating larger structures, such as the hand of an adult man. (They think it takes just a four-millimeter biopsy to get enough tissue to culture 45 million fibroblasts and his 18 million keratinocytes.) , plans to do away with the scaffolding and start printing the actual tissue. Not only does this save some steps, but it also gives you more control over the thickness and function of the skin at different locations.
Tissue engineers are confident that such new approaches will be clinically useful. “It’s really becoming a problem when Is this available?” says Feinberg. If.”
