Myeloid stem cells

Myeloid Stem Cell GCSF-R or GM-CSFR (CD114, CD115, CD116) ... 

Tavian M, Robin C, Coulombel L and Peault B (2001). The human embryo, but not its yolk sac, generates lympho-myeloid stem cells, mapping multipotent hematopoietic cell fate in intraembryonic mesoderm. Immunity 15 487-495. 

G-CSF IL-1, LPS Granulocyte colony stimulation, terminal differentiation of myeloid cells, enhanced neutrophil function — Granulocytes, myeloid stem cells, neutrophils... 

A basic understanding of normal hematopoiesis is needed before one can understand the pathogenesis of leukemia. The reader is referred to Chap. 98 for a detailed discussion of hematopoiesis. Normal hematopoiesis consists of multiple well-orchestrated steps of cellular development. A pool of pluripotent stem cells undergoes differentiation, proliferation, and maturation, to form the mature blood cells seen in the peripheral circulation. These pluripotent stem cells initially differentiate to form two distinct stem cell pools. The myeloid stem cell gives rise to six types of blood cells (erythrocytes, platelets, monocytes, basophils, neutrophils, and eosinophils), while the lymphoid stem cell differentiates to form circulating B and T lymphocytes. Leukemia may develop at any stage and within any cell line. 

CDF/LIF, identified only relatively recently, has become one of the most extensively studied cytokines and turned out to play a remarkable varietyof roles in living organisms. Recent advances in molecular and cellular biological studies of CDF/LIF reveal that this factor has at least three important specific functions in vivo. First, it is essential for blastocyst implantation. Second, it is required for self-renewal of a group of myeloid stem cells. Third, it probably functions as a repair factor following nerve injury and in some host defence systems. It remains, however, unknown in what manner CDF/LIF, as a member of the EL-6 family, interacts with other cytokines and growth factors to fulfil these and other complex physiological functions. 

GM-CSF has wider biologic activity than G-CSF it stimulates early myeloid stem cells in addition to stimulating cells destined to become neutrophils. The answer is (E). 

There are many different cell types in the immune system and these cells interact in a complex reaction of signaling and communication to create the overall response. The cells of the immune system derive from two types of cells in the bone marrowy myeloid stem cells and lymphoid stem cells. Myeloid cells give rise to precursor cells of the innate immune system, whereas lymphoid cells generate precursors of cells of the adaptive immune system. Chemokine receptors are found on almost all immune cells. 

Stocking, C. et al.. Distinct classes of factor-independent mutants can be isolated after retroviral mutagenesis of a human myeloid stem cell Hne, Growth Factors, 8,197,1993. 

Edwards, G. E., Miller, R. G., Phillips, R. A. Differentiation of rosette-forming cells from myeloid stem cells. J. Immunol. 105, 719-729 (1970). 

Hematopoiesis is defined as the development and maturation of blood cells and their precursors. In utero, hematopoiesis may occur in the liver, spleen, and bone marrow. However, after birth, it occurs exclusively in the bone marrow. All blood cells are generated from a common hematopoietic precursor, or stem cell. These stem cells are self-renewing and pluripotent and thus are able to commit to any one of the different lines of maturation that give rise to platelet-producing megakaryocytes, lymphoid, erythroid, and myeloid cells. The myeloid cell line produces monocytes, basophils, neutrophils, and eosinophils, whereas the lymphoid stem cell differentiates to form circulating B and T lymphocytes. In contrast to the ordered development of normal cells, the development of leukemia seems to represent an arrest in differentiation at an early phase in the continuum of stem cell to mature cell.1... 

Broxmeyer HE, Kohli L, Kim CH, et al. Stromal cell-derived factor-l/CXCL12 directly enhances survival/antiapoptosis of myeloid progenitor cells through CXCR4 and G(alpha)i proteins and enhances engraftment of competitive, repopulating stem cells. J Leukoc Biol 2003 73(5) 630-638. 

Bcr-Abl Constitutive activation in the cytoplasm of blood stem cells Chronic myeloid leukemia (CML)... 

It is believed that all blood cells arise from the division and differentiation of multipotent stem cells. These stem cells have considerable capacity for self-renewal by cell division but may also differentiate into progenitor cells of lymphocytic or myeloid lineages (see Fig. 2.1). Experiments with colony-... 

The murine hematopoietic stem cell line Myl-D7 spontaneously differentiate along the lymphoid, myeloid and erythroid lineages. Myl-7 cells shows a strict stromal dependence for growth of self-renewing stem cells and express high levels of CSF-1 receptor (Itoh et al., 1996). We used this cell line to analyze the function of CSF-1 in maintaining multipotent cells. In an other attempt to characterize unknown factors that could sustain stem cells we... 

The stem cell line Myl-D7 not only expresses differentiation markers of all lineages but is dependent for growth on self-renewing stem cells within the Myl-D7 clone which spontaneously differentiates along the lymphoid, myeloid, or erythroid direction (Itoh et ah, 1996). Supernatant of MS5 induces short term growth of Myl-D7 cells. This may indicate that at least soluble stem cell growth factors are secreted by MSS cells. 

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