ZOOGRAFTING - A HISTORY OF XENOGRAFTS IN BURN TREATMENT AND CARE

Objectives: In the United States, over half a million patients require burn treatment annually. Non-fatal burns constitute a major cause of morbidity, including disfigurement, disability, extended hospitalization, and stigmatization. While wound excision and autologous tissue transfer is the gold standard for most burn treatment, patients with extensive burns often lack sufficient donor skin. Skin allografts are often used as temporary additional burn dressings. However, skin donor shortages and high cost can make access to this skin difficult. While synthetic dressings, such as dermal substitutes and acellular products, are also regularly used and have the potential benefit of long-standing wound coverage, they also carry an expense and are not as readily available. Skin xenografts have been used as an alternative and have distinctively served as a temporary low-cost solution for burn patients.

Methods: This presentation recounts the history of skin xenotransplantation in burn treatment.

Results: Beginning in the 16th century, skin xenografts from frog skin were used to treat smaller burns and injuries, and have continued use in Brazil and Vietnam where allograft shortages persist. Despite earlier global attempts, the first recorded skin xenotransplantation in the United States was performed in 1880 in Boston by Dr. E. W. Lee who transplanted a sheep’s skin flap to the back of a young girl with extensive burns. While unsuccessful, the procedure inspired other physician-scientists to attempt xenograft burn treatment with pigeons, rats, rabbits, cats, dogs, pigs, and cows. While mostly unsuccessful, it was not until 1951 that the field transformed when Silvetti and colleagues proposed bovine skin xenotransplantation as a purely temporary biological dressing. In the 1960s, porcine skin xenografts gained popularity due to longer wound adherence, room temperature storage, and efficacy for joint surfaces due to improved joint mobility. Over the next few decades in many countries, bovine and sheep skin xenografts were subsequently improved and refined for temporary excised burn coverage. During more modern times, the Instituto Doutor José Frota in Brazil reported using Nile tilapia skin xenografts with success in 2016, an example of how the xenograft remains a mainstay for burn care in the appropriate setting.

Conclusion: While excision and autography remain a mainstay for burn care, xenografts are used to bridge the gap in burn wound care in settings where allografts are not as readily as available. The history of xenografting is culturally diverse and spans centuries, showing the importance of the material as a skin substitute in burn wound care.