Platelet poor plasma gel combined with amnion improves the therapeutic effects of human umbilical cord­derived mesenchymal stem cells on wound healing in rats.

The aim of the present study was to investigate the efficacy of human umbilical cord­derived mesenchymal stem cell (HUMSCs) embedded in platelet poor plasma (PPP) gel combined with amnion (PPPA) in improving wound healing on Sprague­Dawley (SD) rats. HUMSCs were cultured and labeled with chloromethylbenzamido­1,1'­dioctadecyl­3,3,3'3'­tetramethylindocarbocyanine perchlorate (CM­DiI) on their third passage. The expression levels of growth factors of HUMSCs in PPPA were assessed by ELISA. Full­thickness excisional skin wounds were induced in 36 male SD rats, which were treated with PPPA grafted with HUMSCs (PPPAC), PPPA, or HUMSC or PBS injection. The degree of healing and the distribution of labeled HUMSCs in the wound were evaluated by hematoxylin and eosin (H&E) staining and immunofluorescence. On day 14 post­surgery, wound healing in PPPAC­treated rats was significantly higher than the PPPA group, compared with rats treated with HUMSCs alone and control rats (P<0.05 and P<0.01, respectively). H&E staining showed that morphology and thickness of the epidermis in the PPPAC group was similar to that of healthy skin. ELISA revealed that levels of growth factors of HUMSCs in PPPAC were higher than in monolayer cells. In conclusion, PPPA can modify growth factor expression levels of HUMSCs and improve the efficiency of HUMSCs in the healing of full thickness wounds in rats.