[Experimental study on isolation and cultivation of placenta-derived mesenchymal stem cells and bone marrow-derived mesenchymal stem cells of rabbit and their biological characteristics].

OBJECTIVE

To explore a method to isolate, culture and multiplicate the placenta-derived mesenchymal stem cells (PMSCs) and the bone marrow-derived mesenchymal stem cells (BMSCs) of rabbit, and to compare their biological characteristics.

METHODS

PMSCs were isolated from placenta of 1 fetation rabbit by Percoll density gradient centrifuge and cultured in vitro. BMSCs were isolated from hindlimb bone marrow blood of 1 new born rabbit by direct plates culture method. The 3rd passage PMSCs and BMSCs were observed by inverted phase contrast microscope. The stem cell marker (CD44, CD105, CD34 and CD40L) were examined by immunohistochemistry. The 2nd passage PMSCs and BMSCs were co-cultured with biomaterials, (1.0-1.5) x 10(6) cells in one biomaterial, and then observed by haematoxylin staining after 5 days, and by SEM after 3 days and 8 days.

RESULTS

PMSCs and BMSCs were both uniformly spondle-shaped in appearance and showed active proliferative capacity. The proliferative ability of PMSCs were quite strong and declined with passages. After cultured 10 passages in vitro, its growth slowed. Both PMSCs and BMSCs expressed CD44 and CD105, but did not express CD34 and CD40L immunoreactivity. PMSCs and BMSCs poliferated and adhered to the surface of biomaterials, and cell formed clumps and network; the cells proliferation and the matrix were seen in the pore after 5 days of culture. The observation of SEM showed that many cells adhered to the biomaterials with spindle-shape and polygon after 3 days; and that PMSCs and BMSCs grew, arranged in layers and secreted many matrices; the reticular collagen formed arround cells after 8 days.

CONCLUSION

PMSCs and BMSCs have similar biological characteristics and PMSCs can be served as excellent seeding-cells for tissue engineering.