Abstract

Introduction: Human umbilical cord blood (HUCB) has been frequently used in clinical allogeneic graft transplantation of haematopoietic stem cells (HSCs). However, HUCB has been poorly recognised as a source of mesenchymal stem cells (MSCs). The aim of this study was to establish a new method for large number of MSCs and proving that HUCB is a good source of MSCs.
Method: HUCB was collected from women (n=25) following elective caesarean section. Small amounts of samples were explanted into MesenCult medium and incubated in a 5% CO2 incubator at 37OC. Qualitative and quantitative immunophenotyping of cells was achieved using fluorescein isothiocyanate (FITC) attached to known MSC phenotypic markers (CD29, CD73, CD44 and CD105). Haematopoietic antibodies were used as a negative control (CD34, CD45). MSCs were plated in neurogenic, osteogenic and adipogenic differentiation media. Immunocytochemistry for the embryogenic markers sex determining region Y-box 2 (SOX2) and Oligodendrocyte (OLIG-4), Osteocalcin and Fatty acid binding protein-4 (FABP-4) was carried out.
Results: MSC cultures using the Clot Spot method showed a three-fold increase in proliferation, compared with other methods. Cells expressed MSC markers CD29, CD73 and CD44 and CD105, but lacked expression of CD34 and CD45. Cells also expressed the neural SOX2, Olig4, osteogenic osteocalcin and adipogenic FABP-4 markers following differentiation.
Conclusion: Using novel techniques, it has been demonstrated that umbilical cord blood is a rich source for MSCs. Therefore, it should be considered as a good source of MSCs for potential use in clinical allogenic transplantation