How does BTM work? – Synthetic Graft Interactions in Full-Thickness Wounds Using Mouse Models

Nicole Garcia^1,2, Mostafiz Rahman^1,2, Ilia Banakh^1,2, Cheng Lo^1,2, Heather Cleland^1,2, Shiva Akbarzadeh^1,2,
¹Skin Bioengineering Laboratory, Monash University, Melbourne, Victoria, Australia
²Victorian Adult Burns Service, The Alfred, Melbourne, Victoria, Australia

Abstract

Background and aims: The limited availability of donor skin grafts in large burns becomes a significant challenge. Dermal substitutes are biomatrices that act as scaffolds to fulfil the function of the dermis when donor sites are limited. The mechanism through which dermal substitutes help heal wound beds is largely unknown. Our aim was to study how Biodegradable Temporising Matrix (BTM) modulates normal wound healing following establishment of a full-thickness wound mouse model. Methods: A full thickness wound repair mouse model was established. BTM was applied (‘grafted’) on a full-thickness wound bed next to an ungrafted full-thickness wound on the same hairless mouse. RNA and protein were extracted from the wound bed and analysed for inflammatory (TNF-α, IL-1β, IL-6, CXCL-1), anti-inflammatory (IL-10), proliferation (TGF-β1, VEGF) and remodelling markers (MMP-2, collagen I and III). Experimental results from the full-thickness ungrafted wounds were compared to wound grafted with BTM. Results: Inflammatory markers peaked during inflammation in an ungrafted full-thickness wound. Haematoxylin and eosin staining demonstrated less inflammatory cells in grafted wounds compared to ungrafted wounds. Collagen deposition was significantly higher in wounds grafted with BTM. Wound contraction was significantly lower in wounds grafted with BTM. Inflammatory markers were downregulated in grafted wounds compared to ungrafted, and RNA fold expression of remodelling markers were higher in synthetically grafted wounds. Conclusion: Spontaneous wound repair is altered by the application of BTM. Data so far indicates that it does so in all stages of wound repair.

Biography

Nicole Garcia completed her Master of Surgery in 2020 with the Skin Bioengineering Laboratory at Monash University. She is currently working as a Plastic Surgery Registrar in Victoria, Australia.