Isolation of mononuclear cells from human cord blood by Ficoll-Paque density gradient.

When preparing stem cell specimens from cord blood, pre-enrichment of mononuclear cells is highly recommended to improve the recovery of rare stem cells. Mononuclear cells are easily isolated by density gradient centrifugation. In Ficoll-Paque density gradient centrifugation, anticoagulant-treated and diluted cord blood is layered on the Ficoll-Paque solution and centrifuged. During centrifugation, erythrocytes and granulocytes sediment to the bottom layer. Lower density lymphocytes, together with other slowly sedimenting cells such as platelets and monocytes, are retained at the interface between the plasma and Ficoll-Paque, where they can be collected and subjected to subsequent isolation of hematopoietic stem cells or to the culture of mesenchymal stem cells. Copyright 2007 by John Wiley & Sons, Inc.