CD114 is the receptor of the colony stimulating factor 3 (CSF3, G-CSF), consist of two 130 kD, type I transmembrane chains that form a homodimer. The extracellular domain consists of an immunoglobulin-like domain, a cytokine receptor homologue domain, and three fibronectin type III repeats. CD114 is expressed in all stages of granulocyte differentiation and in monocytes, platelets, endothelial cells, placenta and trophoblasts. The binding of CSF3, results in the activation of many signaling molecules such as Syk, Lyn, Jak1, Jak2, Tyk2, SOCS3, SOCS1, STAT5, and Shp1, resulting in the expression of different target genes that will increase neutrophil precursor survival, proliferation and maturation. In mature neutrophils, it increases survival, superoxide anion generation, arachidonic acid release, production of myeloperoxidase and leukocyte alkaline phosphatase (LAP).