Biomedical Engineering Reference
In-Depth Information
8
Alternative delivery of keratinocytes for
epidermal replacement
F. M. WOOD
McComb Foundation, Burns Service of Western Australia,
University of Western Australia, Australia
Abstract:
In bridging the gap between the laboratory and the patient it is
essential to consider the differences in the environment the cells are exposed
to in order optimize their performance and achieve the goal of expedient
wound closure. Successful delivery systems for keratinocytes to the wound
bed must consider the viability and proliferation potential of the cells with
protection to achieve a mature epithelial layer. The delivery systems are
described in two groups, direct delivery or with the use of carrier. The clinical
use of pre-confluent keratinocytes has been widely reported to be effective in
augmenting wound healing.
Key words:
Keratinocyte suspension, aerosol delivery, pre-confluent cell
delivery, cell carriers.
8.1 Introduction
In bridging the gap between the laboratory and the patient it is essential to consider
the differences in the environment the cells are exposed to in order to optimize their
performance and achieve the goal of expedient wound closure.
1
The development
of the technique of cultured epithelial autograft (CEA) was driven by the need to
achieve wound closure in extensive burn injury with limited skin donor sites.
2
CEA
was used in the form of confluent cell sheets in place of split thickness skin grafts.
3,4
As reports appeared in the literature it was clear that wound healing was possible
with the CEA but problems emerged.
5,6
The time taken to achieve confluent sheets, often greater than three weeks
7
presents challenges in caring for the patient, including infection control, wound
care and pain management. The processes both in the laboratory and operating
theatre are costly, labour intensive and time consuming.
8,9
Subsequent to healing, secondary loss of the CEA healed surface with blistering
is associated with secondary delayed healing and poor scar outcome.
10,11
In
addition, contracture of the scar is a problem with the fragile surface making scar
management more difficult.
12
It has been demonstrated that the keratinocytes change in character from the time
of initial harvest from the dermal epidermal junction as a dissociated cell population,
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