Abstract

Introduction: Human umbilical cord blood (HUCB) has been successfully
used in clinical allogenic graft transplantation of haematopoietic stem cells
(HSCs). However, HUCB has been poorly characterized as a source of
Mesenchymal stem cells (MSCs). The aim of this study was to establish HUCB
as a source of MSCs using a novel clot spot method.
Method:HUCB was collected (n=9) from candidates consenting women, who
underwent elective caesarean section. HUCB clot was meticulously explanted
in MesenCult basal medium and incubated in 5%CO2 incubator at 37°C.
Qualitative and quantitative immunophenotyping of cells was achieved using
fluorescein isothiocyanate (FITC) labelled antibodies reactive with CD34,
CD45, CD29, CD44, CD73 and CD105 antigen markers. MSCs were plated
in neurogenic and adipogenic differentiation media. Immunocytochemistry was
used for embryogenic markers SOX2, Olig4 and FABP-4 identification.
Results: MSC cultures using the clot spot method showed morphological
changes inkeeping with cell lineage differentiation within two weeks of culture
with a three fold increase in number, compared with other methods. Cells were
negative forHSC markers (CD34, D45), but strongly positive for MSCmarkers
CD29 (97%), CD44, CD73 (95%) and CD105 (97%). MSCs expressed the
neural SOX2, Olig4 and adipogenic FABP-4 markers.
Conclusion: HUCB is a good source of MSCs for transplantation, using this
novel technique.