The growth-promoting activity of BPE has been replaced by the inclusion of growth-promoting agents, which enhance consistent product performance. These growth-promoting agents also maintain cell morphology, physiological markers, and growth. The medium is formulated to inhibit fibroblast proliferation and has a low calcium concentration (<0.1 mM), allowing for the isolation and culture of highly enriched populations of undifferentiated keratinocytes.

Defined Keratinocyte SFM is a complete serum free medium consisting of Defined Keratinocyte Serum Free Basal Medium with the addition of Defined Keratinocyte SFM Growth Supplement that eliminates the requirement for bovine pituitary extract. The supplement is supplied in separate packaging with the basal medium.