ABSTRACT
In cases when different stem cells are derived from tissues such as bone marrow aspirate, umbilical cord blood, and mobilized peripheral blood, it is important to eliminate red blood cells and neutrophils. This method is effective by density gradient such as Ficoll-Hypaque. The density will vary depending on the species and this should be noted at the beginning of the method. In the case of isolation of mesenchymal stem cells (MSCs) or stromal cells from the bone marrow, it is critical after three days to eliminate red blood cells (RBCs) by density gradient. This will remove the RBCs before they are lysed, which could be toxic to the adherent cells. Additionally, the isolation of hematopoietic cell subsets from human marrow aspirate would require starting with mononuclear, which would be derived from density gradient. This method describes a step-by-step process to isolate mononuclear cells by density gradient.
