T. Kangesu et al., NERVE AND BLOOD-VESSEL GROWTH IN RESPONSE TO GRAFTED DERMIS AND CULTURED KERATINOCYTES, Plastic and reconstructive surgery, 101(4), 1998, pp. 1029-1038
The aim of this study was to study innervation and angiogenesis in res
ponse to grafts of dermis and cultured keratinocytes using immunohisto
chemical techniques. In a porcine model, fresh autologous de-epidermal
ized dermis and cultured autologous keratinocytes were combined using
a two-stage technique, to produce keratodermal grafts. Wounds were enc
ased within skin graft chambers that prevented the influence of the su
rrounding skin. As grafts contracted, a peripheral rim of granulation
tissue became exposed, allowing us to compare the wound bed beneath gr
afts with that beneath the raw granulating surface. Grafts were studie
d for 6 weeks. Angiogenesis was studied using antisera to von Willebra
nd factor to detect endothelial cells. Nerve growth was studied using
antisera to S-100, a Schwann cell marker, and to four axonal markers:
protein gene product 9.5, C-flanking peptide of neuropeptide Y, calcit
onin gene-related peptide, and vasoactive intestinal peptide. In kerat
o-dermal grafts ( n = 28), organization of blood vessels and nerve gro
wth occurred only beneath areas with epidermal cover as compared with
the surrounding granulation tissue. Initially, the immunoreactivity to
von Willebrand factor was high, but in areas with epidermal cover it
assumed a more orderly pattern with fewer blood vessels. Innervation w
as first detected by S-100 immunoreactivity seen at 1 to 2 weeks, clos
ely followed by that to protein gene product 9.5 and much later to cal
citonin gene-related peptide. C-flanking peptide of neuropeptide Y and
vasoactive intestinal peptide immunoreactivity were detected in the w
ound depth surrounding large blood vessels at 4 to 6 weeks. In control
wounds that had been either grafted with de-epidermalized dermis alon
e (n = 10) or allowed to granulate (n = 10), persistently there was hi
gh immunoreactivity to von Willebrand factor but minimal immunoreactiv
ity to the neural markers. In conclusion, kerato-dermal grafts become
innervated, and beneath their surface there is also vascular organizat
ion to resemble normal skin. Keratinocytes themselves may influence an
giogenesis and innervation, as both processes failed to occur beneath
granulating areas.