{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"CD123 is α chain of the IL-3 receptor. This 60-70 kDa transmembrane protein, by itself, binds to IL-3 with rather low affinity. However, when associated with CD131 (common β chain), the protein binds to IL-3 with high affinity. The gene coding for the receptor is located in the pseudoautosomal region of the X and Y chromosomes. The receptor belongs to the Type I cytokine-receptor family and is a heterodimer with a unique alpha chain paired with the common beta (beta c or CDw131) subunit."}]},{"type":"paragraph","children":[{"type":"text","value":"The CD123 receptor, found on pluripotent progenitor cells, induces tyrosine phosphorylation within the cell and promotes proliferation and differentiation within the hematopoietic cell lines. CD123 is expressed by myeloid precursors, macrophages, dendritic cells, mast cells, basophils, and megakaryocytes."}]}]}