OBJECTIVE

To investigate the expression of Galectins in umbilical cord mesenchymal stem cells (UC-MSCs) from Wharton's jelly.

METHODS

Umbilical cords were obtained sterilely from full term caesarean infants, then mesenchymal stem cells (MSCs) were isolated from Wharton's jelly of the umbilical cord via tissue cultivation. The morphology of UC-MSCs was observed under the optical microscope, and its immunophenotypes were analyzed by flow cytometry. The differentiation of UC-MSCs into the osteoblasts and adipocytes was determined utilizing von Kossa calcium node staining and oil red O staining, respectively. The expression of Galectins at mRNA level was measured by RT-PCR. The levels of secretory Galectin-3 in culture supernatants were detected by sandwich enzyme-linked immunosorbent assay.

RESULTS

The UC-MSCs could be generated by tissue cultivation. Flow cytometry showed they highly expressed membrane molecules, such as CD29, CD44, CD73, CD90 and CD105, but did not express hematopoietic specific markers (CD14, CD34, and CD45) and immune rejection related molecule HLA-DR. UC-MSCs could differentiate into osteoblasts or adipocytes under appropriate experimental conditions. At the mRNA level, Galectin-1, 3, 4, 8 and 9 were detected in UC-MSCs. And they also could secrete soluble Galectin-3 in a cell number dependent manner. Statistical differences were obtained among the different cell number incubation groups (F=16.901,P=0.002). However, the secretory manner of Galectin-3 was not time dependent.

CONCLUSION

UC-MSCs, derived from Wharton's jelly, were successfully cultured via tissue cultivation, and they could express secretory Galectin-3. All these data laid the foundation for further detecting the immunomodulatory mechanism of UC-MSCs.