RPMI, also known as RPMI 1640 or Roswell Park Memorial Institute Medium, was first described by Moore (1967) in successfully culturing and expanding human lymphoid cells. RPMI contains 19 essential and non-essential amino acids including glycine, 11 vitamins, 6 salts, and sodium bicarbonate. It is designed for an environment containing 5% carbon dioxide. RPMI is suitable for cells in suspension or monolayer and is widely used to grow a variety of mammalian cell types. These include primary human leukocytes, bone marrow cells, hybridomas, as well as common cell lines. RPMI typically requires supplementation with serum protein, such as FBS.