Abstract:

Objective This study was designed to evaluate the effect and mechanism of adipose derived stem cells（ADSCs） in the process of promoting fibroblasts proliferation and migration.

Methods ADSCs were obtained from back subcutaneous adipose tissue of porcine with collagenase digestion and cultured in vitro.Flow cytometric analysis and cyto immumofluorescence staining technique were carried to detect the immunophenotypes of ADSCs.Porcine skin fibroblasts were cultured by tissue pieces and cyto immumofluorescence staining technique were used to detect the immunophenotypes of cells.The experiment was divided into ADSCs group and fibroblast group，cell to cell co culture experiment and transwell co culture experiment were used to evaluate the proliferation effect of ADSCs supernatant to fibroblasts.MTT assay was used to detect the proliferation effect of conditioned medium of ADSCs to fibroblasts.Also whether the conditioned medium of ADSCs has the stimulatory effect on migration of fibroblasts were determined by in vitro wound healing models.The concentrations of vascular endothelial growth factor（VEGF）、platelet derived growth factor（PDGF-AA）and transforming growth factor（TGF-β1）in conditioned medium of ADSCs were detected by using enzyme linked immunosorbent assay（ELISA）.

Results The stem cells isolated from subcutaneous adipose tissue were positive for CD44（90.2%） and CD105（99.2%），lacking in CD34（0.3%） and CD45（1.2%）.Porcine skin fibroblasts were positive for Hsp47.ADSCs promoted fibroblasts proliferation，not only by cell-to-cell direct contact，which was confirmed by co-culture experiment，but also by paracrine activation through secretory factors，resolved by transwell co-culture and culturing with conditioned medium of ADSCs（P<0.05）.Additionally，the fibroblasts showed vigorous proliferate and migratory responses to the conditioned medium of ADSCs.ADSCs produced a variety of growth factors：VEGF（765.63±56.23pg/ml），TGF-β1（133.42±24.35pg/ml）and PDGF（78.43±16.56pg/ml）.

Conclusion ADSCs can promote the proliferation and migration of fibroblasts.This study can provide some theoretical and experimental basis for the treatment of wound healing.

Key words: adipose derived stem cells, fibroblasts, proliferation, migration