Could Flatworm Vesicles Replace Skin Grafts? New Research Says Maybe

Quick Take

• Traditional skin grafts carry a hidden flaw that may make them obsolete, but the fix comes from a creature living at the bottom of a pond. See why grafts fall short →
• Flatworms can regrow an entire body from a tiny fragment, and scientists think that same biological trick could seal wounds that refuse to heal. Discover flatworm regeneration →
• One overlooked property of flatworm vesicles could sidestep the immune rejection problem that derails most cell-based wound therapies. Explore the immune advantage →
• Swedish researchers used raw chicken liver to collect the organisms behind a potential wound-healing breakthrough, and the method only gets stranger from there. See the chicken liver method →

The answers to some of medicine’s most challenging problems can come from the most unlikely sources. Who would have thought that a flatworm lurking at the bottom of a Swedish pond could play a role in healing burns and ulcers? We explain the science behind this unlikely link uncovered by new research.

A New Approach to Wound Healing

Wounds that just refuse to heal are an ongoing problem for clinicians worldwide. Traditional cell-based therapies, such as grafting stem cells or skin cells, come with their own set of problems, including immune rejection and finding sufficient cells to meet demand. This has led scientists to consider cell-free options, and that includes extracellular vesicles.

Extracellular vesicles are very tiny (smaller than bacteria) vesicles enclosed in a lipid bilayer. They are produced by cells and are part of cell-to-cell communication. If they could be used in medicine, they would offer a lot of advantages. They trigger little in the way of an immune response, are not toxic, and could be engineered or used with other biomaterials. Extracellular vesicles are already released by cells around the wound and participate in the healing process.

In terms of wound healing, extracellular vesicles do a lot of heavy lifting. They help to regenerate tissue, reduce inflammation, and promote cell proliferation. But where is the best place to get the extracellular vesicles from?

The Amazing Regenerating Flatworm

Freshwater flatworms (planarians) are known for their ability to regenerate entire organisms from small parts! The role of extracellular vesicles in this process is not well understood. However, experts have already established that flatworm extracellular vesicles stimulate stem cell proliferation, which promotes tissue regeneration.

Could extracellular vesicles from a highly regenerative animal, such as the flatworm, be used to help with human wound healing?

How Were Flatworm Healing Powers Studied?

Researchers in Sweden captured wild flatworms using traps baited with raw chicken liver and placed around a pond. The flatworms were cut using a sharp blade, and the extracellular vesicles were isolated through a series of centrifugation steps to separate them from other cellular material.

Once the vesicles had been purified, they were subjected to wound healing studies. First, researchers tested artificial human skin, applying vesicles to some samples from above and to others from below. After three days, fibroblasts—which produce collagen—were present in the deepest layer of the skin. Collagen is essential for healthy skin.

Next, the researchers created wounds on the artificial skin and applied the vesicles. The treated wounds healed much faster than the controls.

What Does This Mean for Wound Healing?

These findings suggest that vesicles from flatworms may accelerate wound healing in laboratory and animal models. Significantly, there was no strong immune reaction. Also, the use of non-human vesicles reduces the risk of pathogen transmission.

While these results are promising, further research is needed before flatworm vesicles could be considered for use in human clinical settings. Nevertheless, this represents a very exciting step forward.