An investigation in the in vitro and in vivo use of microcarrier beads to support keratinocytes and the effect on wound contraction

Full thickness burns and trauma resulting in extensive full thickness skin loss or devitalisation gives rise to the need for skin replacement therapy. Cultured epithelial autologous keratinocytes application has been the main stay treatment over the last three decades. Different methods for cultured...

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Bibliographic Details
Main Author: Eldardiri, M.
Published: University College London (University of London) 2014
Subjects:
617
Online Access:http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.631989
Description
Summary:Full thickness burns and trauma resulting in extensive full thickness skin loss or devitalisation gives rise to the need for skin replacement therapy. Cultured epithelial autologous keratinocytes application has been the main stay treatment over the last three decades. Different methods for cultured epithelial autologous keratinocytes delivery exist with thin epithelial sheet application and sprayed cell culture the most commonly used methods; each method has its advantages and drawbacks. Microcarrier beads for the culture of cells have been utilised in a number of different applications over the last forty years as they allow rapid cell culture and expansion in a controlled environment. More recently microcarrier commercially available gelatin microcarrier beads “Cultispher G®” have demonstrated the potential to support keratinocyte cell culture and proliferation in vitro. Wound contraction is a physiological component of wound healing and occurs within the proliferation phase of wound healing between 4 days to 3 weeks following the inflammatory phase. Wound contraction is a function of myofibroblasts leading to approximation of the wound margins and reduction in wound size. The migration of keratinocytes from the intact epithelium around the wound edges leads to epithelial closure and completes the process of wound healing. This study aimed to assess the use of microcarriers for supporting keratinocyte growth in vitro and evaluate the effect of keratinocyte delivery using microcarriers on wound contraction using a porcine wound model. In this study, in vitro assessment of keratinocyte expansion on microcarriers demonstrated sustainable expansion rates with data being comparable to traditional keratinocyte cell culture. Animal experiments utilising an in vivo porcine model have shown that keratinocytes delivered to the wound bed using gelatin microcarriers migrated off the beads and were shown to survive on the wound bed. In the same animal model, autologous keratinocytes cultured on microcarrier beads reduced wound contraction when applied to full thickness wounds in combination with widely meshed autologous split skin graft compared with split thickness skin graft (STSG) alone or control wounds. The use of allogeneic cultured keratinocytes on microcarriers in combination with dermal regeneration template “Integra®” demonstrated a reduction in wound contraction compared with Integra® and STSG or Integra® alone. The use of autologous cultured keratinocytes and fibroblasts on microcarriers in combination with Integra® reduced wound contraction compared with Integra and cultured keratinocytes or Integra and STSG. The reduction in wound contraction maintained a large area of the original wound surface area, hence reducing the possibility of contracture formation. The use of microcarrier beads for culture and delivery of keratinocytes has the potential to overcome the disadvantages of the traditional methods of keratinocyte culture and delivery. It can also play a role in the reduction of wound contraction resulting in the retention of skin mobility and providing favourable functional and aesthetic outcomes.