Sustained release growth factory delivery with FGF2 DISCs for reproducible 3D cultures
Conventional human pluripotent stem cell (PSC) culture for organoid production requires a rigorous workload, including frequent medium change and technical clean-up of unwanted cells showing spontaneous differentiation. Homogenous PSC cultures are imperative: the quality of the originating PSCs impacts the efficiency and quality of downstream organoid differentiations. It is common to create 3D cultures from multiple PSC lines for comparison using parallel cultures. This can be challenging as lines from different donors often grow differently, leaving scientists struggling to maintain consistency across all lines. The quality of the 3D cultures generated typically cannot be determined until several weeks after production has begun, resulting in unnecessary labor and material waste when poor quality organoids result
Sustained Growth Factor Delivery
This document describes StemCultures DISC technology (Figure 1) that resolves these issues by improving the quality and consistency of PSC-organoid cultures. The DISC device applies controlledrelease technology for cell culture to maintain stable growth factor concentrations and ratios over time. One DISC added to a culture releases the required growth factors at defined concentrations for 1-2 weeks(or until the next passage). DISC devices are composed of a non-degradable, mechanically robust, and inert hydrogel. Cells do not attach to the DISC device, and the DISCs do not directly interact with the cells in culture. DISCs are compatible with any culture medium and can be designed to fit any culture format. Users can change the culture media without removing the DISC device, and the DISC can be cleanly removed to stop growth factor exposure as needed.
FGF2 and High-Quality PSCs
Fibroblast growth factor 2 (FGF2) is a critical signal for maintaining high quality PSCs. FGF2, like many other growth factors, has a short half-life and decays within hours of being added to culture medium. As a result of FGF2 lability, stem cell scientists frequently replenish soluble FGF2 by daily feeding, which results in large fluctuations in FGF2 concentration (Figure 2). These fluctuations expose cells to a changing pattern of signaling which negatively impacts the maintenance of pluripotency and increases unwanted spontaneous differentiation. This type of stress affects PSC lines to unpredictably introduce heterogeneity between cultures. FGF2 DISCs address these limitations by stabilizing the level of FGF2. Using FGF2 DISCsTM, scientists can obtain a new level of control over the PSC cultures environment to obtain homogeneous PSC cultures critical to improve the quality and robustness of 3D organoids.