MCDB 302 medium are modifications of Ham’s nutrient mixture F-12, designed for the growth of human keratinocytes, clonal growth of chicken embryo fibroblasts and chinese hamster ovary (CHO). AT137 is MCDB 302 with trace elements and L-glutamine. MCDB media were developed for the low-protein and serum free growth of specific cell types using hormones, growth factors, trace elements and/or low levels of dialyzed fetal bovine serum protein (FBSP).MCDB 302 were originally developed for human keratinocytes, clonal growth of chick embryo fibroblasts and CHO cells.