Raina Pang
Dec 16, 2011

Hydrogel regenerates burned skin without drugs or biological components

Those following Dancing with the Stars know that this season’s hero was J.R. Martinez. J.R. Martinez was horribly injured in the war and suffered severe burns to over 40 percent of his body. To fix the damage, he underwent 33 surgeries including skin grafts and cosmetic surgery. Since these surgeries, J.R. Martinez continues to work within the burn survivor community and has become a motivational speaker, actor and mirror ball trophy winner.


Third degree burns are extremely damaging to the skin, require complex medical care and result in extensive scarring. Extremely severe burns can require amputation or result in death. Although the prognosis after large burns has improved due to modern treatments, proper regeneration of skin following a burn remains elusive. Scarring after burns still occurs and skin grafts work neither aesthetically nor functionally like unburned skin. Recently, researchers at Johns Hopkins applied a hydrogel to mouse tissue and found that this treatment sped up the process of tissue regeneration and blood vessel formation. This resulted in mature skin with similar morphology and thickness to normal mouse skin. Interestingly, the hydrogel contained no drugs or biological components and consisted mainly of dextran dissolved in water.


People may think of their skin only as it aesthetically functions, but skin provides numerous physical functions such as protection from temperature, water loss, trauma and infection. This makes correct skin regeneration after burn injury essential not only for aesthetic reasons, but also for functional ones. Two ideas examined in skin regeneration are angiogenesis and stem cells.


A critical component for proper tissue repair following burns is the formation of a functioning microvascular system. Angiogenesis and the reestablishment of a proper microvascular system provide necessary nutrients and oxygen to regenerating skin tissue. If this process does not occur correctly, a burn results in worse prognosis and scarring, but if this process is sped up it reduces scarring; thus agents that speed up angiogenesis are likely good targets for improving burn wound healing. Introduction of factors that improve angiogenesis have indeed been explored for burn wound healing and as a way to improve cultured skin substitutes.


The ability for skin to repair itself depends on the presence of stem cells that can generate new skin. This makes stem cell therapy another excellent candidate for burn treatments.  Stem cells exhibit numerous properties that could contribute to wound healing: the ability to differentiate into a variety of cell types, the paracrine effect and immunosuppression. Stem cell therapy appears to improve healing of burn wounds, reduce scarring and can promote the growth of skin with its appendages. Current limitations to these treatments include unknown reestablishment of skin function, potential instability of tissue and controlling for stem cell aging.


Interestingly, the original intent of the hydrogel was a delivery mechanism for angiogenesis growth factors or stem cells. Tests of the hydrogel alone, however, proved promising in the healing process. While the underlying mechanism of the hydrogel is still unclear, it appears to promote angiogenesis and could be recruiting stem cells from the bloodstream. In any case, it seems that the hydrogel creates an environment conducive to healing. As our understanding of regenerative medicine improves, it is clear that the environment plays critical roles in these processes. If similar results occur in humans, this hydrogel could inexpensively replace current clinical therapies for burns. Furthermore, this treatment might also work for other problems requiring skin regeneration and diseases of the vascular system.


Regeneration is a hot topic in biotechnology and spans numerous scientific problems from the ability to regenerate brain cells in neurodegenerative disorders to generating eyes on tadpole’s tails. While numerous techniques prove that regeneration is a possibility, the actual applicability of these techniques to solve complex problems in humans is still unclear.