The Contribution Of Fetal Membrane-derived Mesenchymal Stem Cells In The Acceleration Of Burn Wound Healing

Objective To investigate the separation method and origin of fetal membrane-derived mesenchymal stem cells, and assess the value of fetal membrane-derived mesenchymal stem cells to cure rat full deep burn.Methods Trypsin dispersion method, dispase and trypsin dispersion method, dispase and collagenase dispersion method were used separately to isolate cells from the term fetal membrane. The isolated cells were cultured with Amino-Max II medium. The expressions of CD34, CD45, CD73, CD90 of the cells(passage five) isolated by three kinds of methods refered above were detected using flow cytometry analysis. The DNA of the the cells (passage five) isolated from the male fetal membrane were extracted and detected for their expression of SRY. The acellular dermal matrix(ADM) was coated by gelatin solution with different concentrations of 3mg/ml,5mg/ml,7mg/ml and 9mg/ml. Cell solutions with 5×10~6/ml were seeded on coated and uncoated ADM. Two hours later, the cells inadherent to the ADM were collected for calculating the efficiency of cell seeding. In experimental group, cell(Passage 2 to 3) solutions of 5×10~6/ml were seeded on ADM coated by 7mg/ml gelatin, and were cultured for three to five days. Then the coated ADM with cells was transplanted to SD rat with full-thickness burn. In control group I the ADM without cells was transplanted. In control group II nothing was transplanted. The whole wound surface, wound contraction and the ratio of reepithelization area were calculated weekly. The tissue samples were harvested for histological examination at the fifth week.Result It has been successful in isolating the adherent cells from the human fetal membrane with three kinds of methods. The cells expressed CD73 and CD90, without the expression of CD34 and CD45, which demonstrates that the cells are mesenchymal stem cells. The cells isolated from the male fetal membrane expressed SRY.Conclusion It has been successful in isolating the adherent cells from the fetal membrane with three kinds of methods. The cells have showed the characteristics of mesenchymal stem cells. Different concentration gelatin solutions coated and uncoated ADM didn't show statistical difference in the efficiency of cells seeding. Compared with control groups, experimental group had longer transplantation take, earlier reepithelization, less contraction of wound surface and larger reepithelization area. The thicker regenerated epidermis and more apparent cuticular process and blood capillary were also seen in experiment group.