B8 medium is specifically designed to support the growth and expansion of human pluripotent stem cells, demonstrating its ability to uphold pluripotency across various induced pluripotent stem cell (iPSC) lines as well as embryonic stem cells (ESCs) [1-2].
B8 media is a cost-effective media designed to support cell culture without the need for daily media changes. B8 media is a thermostable version of Essential 8 (E8) Medium, which is xeno-free and feeder-free, meaning it does not contain animal-derived components and does not require feeder cells for cell growth.
B8 medium provides an optimal environment for the maintenance of pluripotency in hPSCs, making it a popular choice among researchers in the field of stem cell biology and regenerative medicine. Additionally, B8 media is often used in various experimental protocols and drug discovery studies involving hPSCs.
The activation of key signaling pathways crucial for maintaining pluripotency is facilitated by specific components within the medium. Fibroblast growth factor 2 (FGF-2) and/or neuregulin 1 (NRG-1) stimulate the PI3K/AKT/mTOR and MAPK/ERK pathways by binding to FGFR1/FGFR4 or ERBB3/ERBB4 receptors, respectively. The TGF-β signaling pathway is activated by factors such as TGF-β1, nodal, or activin A, which bind to receptors TGFBR1/2 and/or ACVR2A/2B/1B/1C. Nodal activation is less common in pluripotent medium formulations due to the presence of nodal antagonists LEFTY1/2 in human pluripotent stem cells (hPSCs). The PI3K/AKT pathway, crucial for promoting cell survival and growth, is activated by insulin or insulin-like growth factor 1 (IGF-1), which bind to insulin receptor (INSR) and IGF1 receptor (IGF1R) respectively. These intricate signaling mechanisms underscore the precise formulation of this medium to sustain the delicate balance of pluripotency in human stem cells.