How stem cells and skin grafts are shaping the future of burn care

I’m never content with the same old burn treatments. I love pushing the envelope and learning new and better ways to care for my patients.

Not only that, but our patients expect the most advanced burn care possible. That means we have to be on the leading edge of research and study in this area of healthcare. And we are.

Our researchers at the Firefighters’ Burn and Surgical Research Laboratory have studied and improved three highly effective burn treatment tools: animal skin grafts, stem-cell skin grafts and laser therapy.

Skin grafts from animals

The first known use of a skin graft to treat a burn wound was reported in 1881. Since then, skin grafting has become a mainstay of burn treatment that continues to evolve.

One type of skin graft we perform is called a xenograft. A xenograft uses animal skin to cover a burn wound while the patient’s skin heals underneath. It’s only temporary, but it’s an effective approach we can use to promote healing.

A xenograft uses animal skin to cover a burn wound while the patient’s skin heals underneath. via @MedStarWHC

fish skin graft
Fish skin graft

We usually use pigskin in xenografting procedures. But some patients prefer not to use pigskin for religious or other reasons. One alternative we’ve tested with a few patients is fish skin. What’s interesting to me is that the indentation from the fish scales still are visible while the temporary graft is in place!  

For more permanent solutions, we turn to grafts from human skin. An awesome approach would be to grow skin from the patient in a lab and then use that skin for the graft. Right now, the only way to do that is by taking cells from the patient and growing them with cells called fibroblasts. Fibroblasts are the active cells in connective tissue, and the ones we use in skin grafts come from mice. Combining skin cells from the patient and mouse fibroblasts produces a substance called cultured epidermal autograft, or CEA.  

The Food and Drug Administration (FDA) hasn’t approved CEA because it uses mouse fibroblasts, so we’re working with researchers at Georgetown University to develop chemical alternatives to the mouse cells. We’re hopeful that this will revolutionize the field of skin regeneration.  

Skin grafts from stem cells

Some of the latest research in skin grafts for burn treatment comes from the use of stem cells. Stem cells can grow into many different types of cells. They also can copy themselves many times, unlike some other cells of the body. These two factors make them useful in creating skin for skin grafts.  We’ve participated in clinical trials for a procedure to actually spray skin onto a burn wound. This technique harvests a patient’s stem cells to create a solution that a doctor sprays onto the wound. If everything goes as planned, skin will begin to grow back at the burn site. As of January 2017, we are in the second phase of a clinical trial for this procedure, and the manufacturer is seeking FDA approval.   

We’ve participated in clinical trials for a procedure to actually spray skin onto a burn wound. via @MedStarWHC

We’re also researching treatments that use substances released by stem cells known as stem-cell-secreted factors. A major problem in burn care is wounds that get worse after the initial examination and diagnosis. This process is called burn wound progression, and it can make treating burns even more challenging. So far, we’ve found that stem-cell-secreted factors can keep burn wounds from progressing and help them heal faster.  

Talk to your doctor about whether you’re a good candidate for one of our research studies.  

Treating burn scars with lasers

Burn scars can be big, itchy and embarrassing for patients, so reducing or eliminating burn scars is something patients often ask about. And lasers have been used for many types of dermatological conditions – though not commonly for burns. So I was surprised when patients began to ask about using lasers to treat their burn scars.  

At first, I didn’t have an answer for them. There hasn’t been much research into the process, so I decided to learn all I could. I joined the American Society for Laser Medicine & Surgery, started going to meetings, and learned that laser treatment for burn scars does seem to be effective, despite limited research.  

This revelation led us to buy a fractional CO2 laser to better understand how laser therapy works for burn patients. In addition to offering laser therapy to some patients, we’re going to start a clinical trial offering early laser therapy free to selected burn patients. We’ll be working with our colleagues in the Department of Dermatology on this trial. We’ll also work in the lab on models that investigate several aspects of laser therapy for burn scars, such as:

  • Amount of power to the laser
  • How much laser therapy is needed
  • Timing of when patients receive laser therapy
  • Whether blending laser therapy with other treatments can be helpful  

Advanced burn diagnosis and wound healing

An early, accurate burn diagnosis helps doctors decide whether a patient needs specialized treatment or basic care and observation.  

We hope to improve that with a new technique for infrared imaging, which was developed by a biomedical engineering student in our lab. The new technique gives us more information about a burn wound right from the beginning and improves on the forward-looking infrared, or FLIR, system that’s currently in use. Once the patenting process is complete, we hope to collaborate with the company that manufactures the infrared camera to put the process to wider use.  

Another issue in the early stages of burn care involves the removal of dead tissue from a burn wound — a process known as debridement. To promote healing, we must remove enough dead tissue while preserving as much live tissue as possible.  

We’ll soon start a study on a new technique that uses an enzyme for wound debridement. The doctor will simply wipe this enzyme onto a burn wound, and the enzyme will remove just the dead tissue from the wound, leaving the live tissue in place for better healing.  

I’m excited to see the results of our research, and I’m eager to learn about the new ways in which we’ll be able to better care for our patients in the months and years to come. 

Why burn scars itch and how to find relief

As many as 90 percent of burn patients report itching after their injuries, according to data cited by the Phoenix Society for Burn Survivors. Itching usually subsides over time, but more than 40 percent of one study’s participants reported long-term itching after their initial burn.

Chronic itching on a burn wound is annoying and can be tough to control. But there are treatment methods that have helped relieve our patients’ symptoms at the Burn Center. Let’s discuss why burn wounds itch, available treatments and what our researchers are doing to relieve post-burn itching for future burn patients. 

What causes burn scars to itch?

Itching is known medically as pruritus. Itching often is caused by a substance called histamine. Histamine is a key part of the body’s immune system. It produces many of the symptoms we associate with allergic responses, including swelling, rashes and itchiness.

In this process, your body recognizes some foreign agent — something you’re allergic to, such as pollen or grass — on your skin. That causes your immune system to fight off the invader and release histamine, which causes itching.  

Some itching after a burn is a normal part of the healing process. But itchiness at burn scars isn’t caused by histamine. In this form of itching, nerves misreport an itch on the skin at the burn site, but the irritation actually is coming from the central nervous system. This is a condition known as central itch — basically an internal itch that can’t be scratched. A bigger or more serious burn doesn’t necessarily lead to worse itching at the scar. 

What treatments provide relief for burn scar itching?

The traditional treatment for itchiness is antihistamine. But because central itch isn’t caused by histamine, antihistamine pills and most itch-relief creams won’t always help.  

It may be tempting to scratch an itchy burn wound or scar, but that’s not a good long-term solution. In fact, scratching can damage fragile, healing skin, which is a particular concern for patients who have had skin grafts to treat burns.  

Some of my patients find relief with lidocaine ointment. Lidocaine can temporarily numb the area of skin where it’s applied. Other patients look to alternative treatments to relieve the itch, including:

  • Acupuncture
  • Hypnosis
  • Massage
  • Reiki therapy (a Japanese technique for relaxation and stress relief)  

Many of these alternative therapies help patients focus on something besides the itching. They don’t eliminate the sensation, but it’s not as persistent or top-of-mind as it ordinarily would be.

Some patients can’t find anything that helps with the itch and just live with it. For others, their itchiness comes and goes. There hasn’t been much research on why the symptom varies and what we can do about it — until now.  

If you have itching at a burn site that persists for months or years afterward, talk to your doctor about your treatment options and whether you need a referral to a burn specialist. 

New research into treating burn scar itching

Our early research into burn care focused on emergency care and preventing infections. We’re now turning our attention toward techniques for patients who are living with burn scars after treatment. We’re just starting to get data from patients who have lived with burn scars for 10, 15 or even 20 years. This information will guide our future treatment decisions.  

As of December 2016, we’re enrolling patients in a study to test a medication we could potentially use to treat central itch. We registered the study’s first participant nationwide just before the holidays in 2016, and we’ll be signing up more participants soon.  

We hope to better understand in the coming years why post-burn itching happens and what we can do to stop it. For now, pain-relieving medications and alternative techniques are our best weapons against itchy burn scars.