MEF from ScienCell Research Laboratories are isolated from embryonic day 13 CF1 mouse embryos. These cells are cryopreserved at P0 and delivered frozen. Each vial contains 1 x 10^6 cells in 1 ml volume. MEF are characterized by immunofluorescence with antibody specific to fibronectin. MEF are negative for mycoplasma, bacteria, yeast, and fungi. MEF are guaranteed to further expand for 5 population doublings under the conditions provided by ScienCell Research Laboratories. This product is for research use only. It is not approved for human or animal use, or for application in in vitro diagnostic procedures.