Establishing ideal culture methods has been a known challenge in human pluripotent stem cell (hPSC) research since the creation of the first embryonic stem cell line in the late 90s and the discovery of induced pluripotent stem cells in 2006. Traditional protocols often call for highly variable components such as cell feeder layers, due to their ability to aid cell maintenance through secretion of essential growth factors, ECM components, and cytokines including bFGF, TGF-β, laminin, and others.¹ However, as the need for more defined cultures becomes increasingly prevalent, carefully formulated microenvironments have since evolved for more efficient maintenance of cellular pluripotency and purity, in turn reducing the use of feeder layers. Ultimately, as standards for clinical-quality cell use in therapeutic applications are determined, media formulations and culture conditions must be refined and optimized while fully supporting proper phenotype and genetic stability.
Today, for clinical translation of hPSCs into cellular therapy, the recommendation is to culture and expand these cells in xeno-free environments that oftentimes utilize recombinant human cell culture substrates like vitronectin. One option for xeno-free culture when using vitronectin is Essential 8™ Medium (E8), but when compared to Biological Industries’ NutriStem® hPSC Medium, E8 contains extensive amounts of growth factors with the intention of maintaining pluripotency and preventing differentiation.²