Skin repair using a porcine collagen I/III membrane--vascularization and epithelization properties.
BACKGROUND
Collagen membranes have been developed to overcome the problem of limited availability of skin grafts. Vascularization and restricted functional epithelization limit the success of bioartificial constructs.


OBJECTIVE
To compare the vascularization, epithelization, and integration of a porcine collagen I/III membrane with that of split-thickness skin grafts on skin wounds.


METHODS
In 21 adult pigs, full-thickness skin defects on the rear side of the ear healed by split-thickness skin grafting, by covering with the membrane, or by free granulation. Skin samples on postoperative days 1, 3, 7, 14, 21, and 28 were evaluated histologically (hematoxylin-eosin, Sirius Red) and using immunohistochemistry (cytokeratin 5/6, transforming growth factor beta receptor (TGFbetaR-III) and immunoblot (TGFbeta(1,3), Smad2/3). Epithelial thickness and TGFbetaR-III-positive capillary area were quantitatively assessed.


RESULTS
Epithelization and vascularization in the membrane group were not significantly different from in the group treated with a split-thickness skin graft. Free granulation showed significantly slower epithelization and vascularization (p<.05). TGFbeta(1) and Smad2/3 complex expression were high during free granulation. Matrix was distinguishable until day 7.


CONCLUSIONS
This membrane serves as a suitable full-thickness dermal substitute, because the membrane is vascularized faster than free granulation tissue and enables early epithelization.
Wehrhan
Falk
F
Department of Oral and Maxillofacial Surgery, Friedrich-Alexander-University of Erlangen, Glueckstrasse 11, 91054 Erlangen, Germany. Falk.Wehrhan@uk-erlangen.de
Nkenke
Emeka
E
Melnychenko
Ivan
I
Amann
Kerstin
K
Schlegel
Karl A
KA
Goerlach
Christoph
C
Zimmermann
Wolfram-Hubertus
WH
Schultze-Mosgau
Stefan
S
D000818:Animals; D024042:Collagen Type I / Q000627:therapeutic use*; D024061:Collagen Type III / Q000627:therapeutic use*; D020405:Dermis / Q000098:blood supply / Q000293:injuries* / Q000473:pathology; D018919:Neovascularization, Physiologic / Q000502:physiology; D017768:Skin, Artificial; D051896:Smad Proteins, Receptor-Regulated / Q000378:metabolism; D013552:Swine; D054457:Tissue Scaffolds; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*; D014950:Wounds, Penetrating / Q000378:metabolism / Q000473:pathology / Q000628:therapy*
D024042:Collagen Type I; D024061:Collagen Type III; D051896:Smad Proteins, Receptor-Regulated; D016212:Transforming Growth Factor beta