RESUMO
<p><b>OBJECTIVE</b>Clinical transplantation evidence has been indicated that umbilical cord blood (UCB) can be useful in the hematopoietic reconstitution in the children, but can not be well in the adult hematopoietic transplantation because of the low count. This study was to evaluate a new method for collecting stem cells from human placenta and umbilical cord, and to comparatively analyze the similarity and difference of quality and quantity of the cells.</p><p><b>METHODS</b>The UCB was collected, in same time the placental tissue was sterily collected; the umbilical placenta was collected by perfusing the blood (UPB) cord arterial and venous vascules with 0.9% saline; the mesenchymal stem cells (MSC) from same source of umbilical cord and placental tissues were isolated and cultured. The cell colony assay and flow cytometry were performed to determine the proliferation capacities and cell markers of UMSC and PMSC.</p><p><b>RESULTS</b>The total nuclear cells (NC) and hematopoietic stem cells (CD34(+)) from UPB and UCB were (17.45 ± 16.86) × 10(8), (6.9 ± 4.61) × 10(8) and (2.97 ± 2.25) × 10(6), (1.91 ± 1.7) × 10(6), respectively. Furthermore, the UPB contained more early precursor of hematopoietic stem cells (CD33(+) CD34(-)) (6.2 ± 13.5) × 10(5), (0.2 ± 0.8) × 10(5) ; and high proportion of MSC to NC (25.21 ± 18.69, 0.05 ± 0.10)%, respectively in 62 samples. There were no difference of the MSC level in UPB and UCB, as well as in the morphology and cell markers.</p><p><b>CONCLUSION</b>UPB has rich hematopoietic stem cells and mesenchymal stem cells. Placenta may offer another source for hematopoietic stem cells in research of hematopoietic stem cells and regeneration medicine.</p>