Dulbecco's Modified Eagle Medium (DMEM) is a widely used basal medium for supporting the growth of many different mammalian cells. Cells successfully cultured in DMEM include primary fibroblasts, neurons, glial cells, HUVECs, and smooth muscle cells, as well as cell lines such as HeLa, 293, Cos-7, and PC-12. Dulbecco's Modified Eagle Medium (DMEM) is modified to contain four times the amino acid and vitamin concentration of original Eagle's Minimal Essential Medium. Like the original DMEM formulation, this formulation contains a low concentration of glucose (1 g/L). DMEM also uses a sodium bicarbonate buffer system, allowing for maintenance of physiological pH in a 5–10% CO2 environment. Importantly, DMEM commonly requires fetal bovine serum (FBS) supplementation.