Source
HSCs are found in the bone marrow of adults; within femurs, pelvis, ribs, sternum, and other bones. Cells can usually be obtained directly from the iliac crest part of the pelvic bone, using a special needle and a syringe. The cells removed are of two forms; as a smear and as a core biopsy. They are also collected from the umbilical cord blood following pre-treatment with cytokines, such as G-CSF (granulocyte colony-stimulating factors), that induce cells to be released from the bone marrow compartment. Other sources for clinical and scientific use include umbilical cord blood, peripheral blood (a small number of stem and progenitor cells circulate in the bloodstream). In the past 10 years, researchers have found that they can coax the cells to migrate from marrow to blood in greater numbers by injecting the donor with a cytokine, such as granulocyte-colony stimulating factor (GCSF) and a recent study has shown that ex-vivo expansion of HSCs is possible in a 3D bioreactor. It is now well described in mammalians that the first definitive HSCs are detected in the AGM (Aorta-gonad-mesonephros), and then massively expanded in the Fetal Liver prior to colonising the bone marrow before birth. Such fundamental research could help to understand the mechanisms that are responsible for HSCs generation and/or amplification, and to the discovery of new molecules that could eventually be used to maintain or expand HSCs in vitro.
Read more about this topic: Hematopoietic Stem Cell
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