Stem Cell Therapy for Burns: Story so Far

Najath Abdul Kareem,1 Ayesha Aijaz,1 Marc G Jeschke1– 4 1Sunnybrook Research Institute, Toronto, ON, Canada; 2Department of Surgery, Division of Plastic Surgery, University of Toronto, Toronto, ON, Canada; 3Department of Immunology, University of Toronto, Toronto, ON, Canada; 4Ross Tilley Burn Centre, Sunnybrook Health Sciences Centre, Toronto, ON, CanadaCorrespondence: Marc G JeschkeRoss Tilley Burn Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Rm D704, Toronto, ON, M4N 3M5, CanadaTel +1 416-480-6703Fax +1 416-480-6763Email marc.jeschke@sunnybrook.caAbstract: Burn injuries affect approximately 11 million people annually, with fatalities amounting up to 180,000. Burn injuries constitute a global health issue associated with high morbidity and mortality. Recent years have seen advancements in regenerative medicine for burn wound healing encompassing stem cells and stem cell-derived products such as exosomes and conditioned media with promising results compared to current treatment approaches. Sources of stem cells used for treatment vary ranging from hair follicle stem cells, embryonic stem cells, umbilical cord stem cells, to mesenchymal stem cells, such as adipose-derived mesenchymal stem cells, bone marrow-derived mesenchymal stem cells, and even stem cells harvested from discarded burn tissue. Stem cells utilize various pathways for wound healing, such as PI3/AKT pathway, WNT-β catenin pathway, TGF-β pathway, Notch and Hedgehog signaling pathway. Due to the paracrine signaling mechanism of stem cells, exosomes and conditioned media derived from stem cells have also been utilized in burn wound therapy. As exosomes and conditioned media are cell-free therapy and contain various biomolecules that facilitate wound healing, they are gaining popularity as an alternative treatment strategy with significant improvement in outcomes. The treatment is provided either as direct injections or embedded in a natural/artificial scaffold. This paper reviews in detail the different sources of stem cells, stem cell-derived products, their efficacy in burn wound repair, associated signaling pathways and modes of delivery for wound healing.Keywords: stem cells, burn injury, exosomes, conditioned media, wound healin