Abstract:

 Objective To establish the culture methods of Wharton’s jelly mesenchymal stem cells from human umbilical cord（hWJ-MSCs）and observe the biological characteristics. Methods The umbilical cord organization of healthy full-term caesarean section was collected under sterile condition. The WJ was diced into cubes of approximately 0.5 mm3, and then plant them in culture flasks which kept still in 3 h before adding L-DMEM with 100 ml/L fetal bovine serum. The WJ-MSCs were passaged using 1.25 g/L Trypsin when they reached 90% confluence. Vimentin was tested by immunocytochemistry. The cell phenotype of WJ-MSCs was detected by flow cytometry. The hWJ-MSCs can differentiate into adipocytes like cell identified by oil-red stain. WJ-MSCs were cultured in medium containing 0.05 g//L Astragalus, then tested the expression of GFAP, NF, Nestin and NSE by immunocytochemical staining. Results Some cells swam out from the tissue block for 6 days or so, which belong to fibroblast-like cell appearing long spindle shaped fibroblast-like cells. WJ-MSCs after subculture presented in a uniform spindle morphology shape, showing parallel growth or vortex growth. The marks of MSCs such as CD90 were positive. The expression of CD34 was negative. Immunocytochemical staining showed WJ-MSCs expressed Vimentin with strong positive. After adipocyte like cells committed induction, these cells with lipid vacuoles accumulated in the cytoplasm gradually could be stained by oil-red O. After committed induction in 24 h by Astragalus, the differentiated cells were stained by Nestin and NF, but GFAP and NSE were negative. Conclusions WJ-MSCs can be effectively obtained from Wharton's jelly with the planting culture, which possess multi-differentiated capability.

Key words: Mesenchymal stem cells, Umbilical cord, Wharton's jelly, Isolation, Culture