Megakaryocyte growth factors

Plasmacytoma growth factor Megakaryocyte growth factor Macrophage progenitor ceil growth factor Adipocyte inhibition... 

Production of blood cells in bone marrow of the central axial skeleton is referred to as medullary hematopoiesis. Hematopoietic tissue in adult bone marrow is well perfused and contains fat cells (adipocytes), and various types of blood and blood precursor cells encased within a protein matrix. Fibroblast, stromal and endothelial cells within bone marrow, serve as sources of matrix proteins as well as a factory for growth factors and chemokines that regulate blood cell production and release matured cells into the circulation [2,3]. Chemokines act as signal lamps for trafficking of lymphocytes in and out of lymphoid tissues. Erythroblasts, neutrophils, lymphoblasts, macrophages, megakaryocytes, and pluripotent stem cells are also found within the calcihed lattice crisscrossing the marrow space. 

Oprelvekin, human recombinant IL-11, a thrombopoietic growth factor that stimulate stem cells and megakaryocyte progenitor, produced in E. coli... 

Interleukin-11 acts through a specific cell surface cytokine receptor to stimulate the growth of multiple lymphoid and myeloid cells. It acts synergistically with other growth factors to stimulate the growth of primitive megakaryocytic progenitors and, most importantly, increases the number of peripheral platelets and neutrophils. 

Stem cell factor amplifies the proliferation and mobilization of myeloid, erythroid, and megakaryocyte colonies when combined with a lineage-specific hemopoietic growth factor (for example G-CSF, IL-3). Stem cell factor, added to other recombinant hemopoietic cytokines, is used to increase the mobilization of peripheral blood progenitor cells. 

Fava, R. A., Casey, T. T., Wilcox, I, Pelton, R. W., Moses, H. L., and Nanney, L. B., Synthesis of transforming growth factor-beta 1 by megakaryocytes and its localization to megakaryocyte and platelet alpha-granules, Blood, 76, 1946, 1990. 

Rl 1. Rennick, D., Jackson, J., Yang, G., Wideman, J., Lee, F., and Hudak, S. Interleukin-6 interacts with interleukin-4 and other hematopoietic growth factors to selectively enhance the growth of megakaryocytic, erythroid, myeloid, and multipotential progenitor cells. Blood 73,1828-1835 (1989). 

Oprelvekin is an interleukin. Interleukin 11 (lL-11) is a thrombopoietic growth factor that directly stimulates the proliferation of hematopoietic stem cells and megakaryocyte progenitor cells and induces megakaryocyte maturation, resulting in increased platelet production. It prevents severe thrombocytopenia and reduces the need for platelet transfusions following myelosuppressive chemotherapy in patients with nonmyeloid malignancies. 

C. Megakaryocyte Growth Factors Oprelvekin (interleukin-11, lL-11) and thrombopoietiii... 

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