Granulocyte Colony-Stimulating Factor (G-CSF) is a 18.67 kDa protein containing 207 amino acid which secreted by monocytes, macrophages, fibroblasts, and endothelial cells, regulates cell growth, maturation, and development of myeloid cells. G-CSF is a member of the CSF family of glycoproteins, and makes the bone marrow produce more white blood cells so it can reduce the risk of infection after some types of cancer treatment. G-CSF is also an established useful clinical agent for increasing neutrophilic granulocytes levels. Mouse G-CSF shares 73% sequence homology with human G-CSF.