Biomedical Engineering Reference
In-Depth Information
substitutes, an autograft (biosynthetic skin substitutes and autolo-
gous cultures/noncultured skin engineering products) is the best
replacement for lost skin; however, in clinical practice this is not
always possible, particularly in large total-body surface area burns,
as there is often an insu
cient amount of skin for autografting
available at the time of burn excision or the physiological condi-
tion of the patient precludes the harvesting of skin. Furthermore,
most skin substitutes are expensive, and considerable experience is
required to decide which material is appropriate for any given sit-
uation. These are allografts and xenografts. These can be used to
provide temporary wound coverage, but there are issues with graft
rejection, availability, cultural and ethical implications, and the pos-
sibility of disease transfer.
10
Tissue-engineered skin is one of the
mostadvancedtissueconstructs,yetitlacksseveralimportantfunc-
tions such as skin appendages and immune cells, and it is di
cult
torecreatetheentirehumanskin.Genetherapycanbeusedforbet-
terfunctionaltissueandthehealingprocess.
11
Recently,multipotent
skin stem cells have been applied to promote tissue regeneration
andtopreventscarformation.
12
Forexample,theapplicationofhair
folliclebulgecells(HFBCs)anddermalpapillacells(DPCs)wasillus-
tratedinanexperiment.
13
Theapplicationofautologousorallogenic
stem cells in combination with specific growth factors in artificial
skin substitute may also help.
2
39.2 Scaffolds: Biomaterials as One of Important Factors
for Regeneration of Skin Tissue
In tissue engineering emerging at the end of the 1980s, two
important factors are generally known, biological characteristics
of cells and biocompatible scaffolds. When cells are used, donor
tissue is dissociated into individual cells, which are expanded
in culture, attached to a support matrix, and re-implanted after
expansion. Among those factors, biocompatible scaffolds are impor-
tant for maintaining tissue architecture. Only isolated cell have
a limited capacity to reform their respective tissue structure,
because they lack a template that guides in restructuring. Moreover,
Search WWH ::
Custom Search