Objective: To construct a tissue-engineered skin flap using composite skin and adipose tissue constructed by adipose-derived stem cells(ASCs).
Methods: Human ASCs isolated from adipose tissue were cultured and identified for their adipogenic, osteogenic and chondrogenic differentiation potentials. ASCs were then mixed with collagen gel for adipogenic induction and observed 15 days later with inverted microscope, oil-red O staining and HE staining. To construct the composite skin, keratinocytes and fibroblasts were isolated from human foreskin. The fibroblasts were mixed with collagen gel and cultured for 5 days, and keratinocytes were seeded on the gel for 4 days before transfer of the culture to air-liquid interface for culture for another 10 days. The adipose tissue and composite skin were then assembled according to the structure of normal skin and cultured for 3 days with HE staining observation.
Results: The cultured ASCs were capable of adipogenic, osteogenic and chondrogenic differentiation, and adipogenic induction of the ASCs-gel complex for 15 days resulted in adipogenic differentiation of the ASCs in gel. The assembled tissue-engineered skin consisted of 3 layers, including a suprabasal layer formed by the stratified and differentiated keratinocytes, the middle layer and sublayer containing numerous cells, and a underlying sublayer formed by the adipogenic ASCs.
Conclusion: Tissue-engineered skin flap can be constructed by assembling composite skin and adipose derived from cultured keratinocytes, fibroblasts, and ASCs.