mesenchymal stem cell products for HUMAN CELLS
mesenchymal stem cell products for MOUSE CELLS
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The bone marrow stroma was originally thought to function mainly as a structural framework for the hematopoietic component of the marrow. Since then, it has become well established that the stroma consists of a heterogeneous population of cells, a subset of which exerts both positive and negative regulatory effects on the proliferation and differentiation of hematopoietic stem cells (HSC) in the marrow through a combination of physical and chemical signals.1-3 The stroma also contains other non-hematopoietic cells termed mesenchymal stem cells (MSC), that are capable of both self renewal and differentiation into bone, cartilage, muscle, tendon and fat.4 MSC are similar to HSC in that they are very rare, existing at an estimated frequency of about 1 in 100,000 bone marrow cells.5 MSC also give rise to a variety of mature cell types via a step-wise maturation process similar to hematopoiesis, termed mesengenesis. Assays have been developed to demonstrate the ability of the cells to generate osteogenic (bone) cells.6 Like their hematopoietic cousins, the cell surface phenotype of the mesenchymal precursor cells present in the marrow has remained elusive. However, they may be quantified in vitro using the colony forming unit-fibroblast (CFU-F) assay. The cultured cells derived from the fibroblast colonies can be further expanded over a number of passages, after which they retain their ability to differentiate into a variety of mature cell types. Although more primitive mesenchymal precursors likely exist, these traits have led many researchers to refer to these cultured cells as Mesenchymal “Stem Cells? and their surface phenotype has been defined as being negative for CD45 and CD34 and positive for SH2, SH4 and CD90 (Thy-1)4.
StemCell Technologies offers products for both the enrichment and culture of human mesenchymal cells. Human mesenchymal progenitors can be rapidly and easily enriched directly from unprocessed bone marrow using the RosetteSep. Mesenchymal Enrichment Cocktail and a simple Ficoll spin. MSC can then be quantified in the CFU-F assay using MesenCult , a specially formulated liquid medium and pre-screened supplements. Additionally, MesenCult can be used to expand MSC in vitro, after which the cells retain their ability to differentiate along various lineages upon the addition of the appropriate stimulatory supplements. Also available are MesenCult basal medium and supplements for the culture and expansion of mouse mesenchymal cells.
CFU-F assay Light density or ammonium chloride-treated human bone marrow cells are cultured in MesenCult medium in 100 mm tissue culture treated dishes and incubated at 37°C, 5% CO2 for 14 days. At the end of the culture period, the medium is removed from the plate. Residual non-adherent cells and medium are removed by washing with phosphate buffered saline. The adherent CFU-F colonies are fixed with methanol and stained with Wrights Giemsa.
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