Launched earlier this year, Essential 8 Flex is a highly optimized, xeno-free and feeder-free pluripotent stem cell (PSC) medium that eliminates the need for weekend feeding. The formulation is based on the Essential 8 medium published by Guokai Chen et al. in James Thomson’s laboratory and later validated by Cellular Dynamics International. As such, it provides the same benefits of Gibco Essential 8 Medium, with increased flexibility.

Challenges with daily feeding

With most PSC culture, there is a need to have daily feeding to maintain pluripotency and tri-lineage differentiation potential. As a result, scientists need to be in the lab 7 days a week. This often means that the same scientist won’t be culturing the cells daily as these tasks need to be delegated on days off. With more people involved in culturing, the risk of introducing variability increases. In addition, it makes scheduling a challenge since there needs to be someone in the lab daily, even on weekends and holidays.

Gibco Essential 8 Flex

With Essential 8 Flex medium, cells only need to be fed on the day of splitting and the day after, if the cells will go without feeding for more than 48 hours then the feed volume just needs to be doubled on the last feed day. Another benefit is that Essential 8 Flex Medium does not require substantial split-ratio adjustments or other significant protocol changes prior to the break in feeding. By eliminating the need for daily feeding, the same scientist can manage the culture throughout thus reducing variability and scheduling conflicts.

Essential 8 Flex adds the benefit of flexibility without compromising the quality of the culture:

• Essential 8 Flex retains nearly 90 percent FGF2 activity after 72 hours, unlike most other feeder-free medium available
• It has been shown to support PSC growth for >50 passages with no signs of karyotypic abnormalities.
• Demonstrates comparable morphology to cultures in Essential 8 medium
• It is able to maintain the ability of iPSCs to differentiate into all three germ line lineages.

For more information about Essential 8 Flex medium, please see Essential 8 Flex.