The Combined Effects of Bone Marrow-Derived Mesenchymal Stem Cells and Microporous Porcine Acellular Dermal Matrices on the Regeneration of Skin Accessory Cells In Vivo.

We investigated the effects of microporous porcine acellular dermal matrices (MPADM)-containing bone marrow-derived mesenchymal stem cells (BMMSCs) on accessory skin cell regeneration in vivo. Two kinds of the porcine acellular dermal matrices were prepared: one with microsized pores (the MPADM) and another without pores (the PADM). BMMSC populations from a Sprague-Dawley (SD) rat were seeded on both PADMs and MPADMs and cultured in vitro for 5 days. These rats were randomly divided into four groups: BMMSCs on an MPADM and covered with a PADM layer (group A), MPADM without cells and covered with a split-thickness skin graft (SSG) (group B), BMMSCs on an MPADM and covered with an SSG (group C), and BMMSCs on a PADM and covered with an SSG (group D). On post-surgery day (PSD) 5, all groups survived, except for group D. On PSD 7, there was no significant difference in the functional vascularization between groups A, B, and C. On PSD 14, large quantities of new capillaries, a larger rough endoplasmic reticulum in fibroblasts, and de novo unmyelinated nerve endings could be observed at the junction between the skin graft and the dermal matrix in group C; however, these structures were absent in groups A and B. The experimental results showed that MPADM could induce exogenous differentiation of BMMSCs in vivo and promote reconstruction of skin accessory cells.