Exploring the Frontiers of Stem Cell Culture with Advanced FGF2 Variants

Exploring the Frontiers of Stem Cell Culture with Advanced FGF2 Variants

Exploring the Frontiers of Stem Cell Culture with Advanced FGF2 Variants

For the field of induced pluripotent stem cell (iPSC) culture to serve basic research, clinical applications, and agriculture, we need to develop and characterize specialized growth factors like FGF2 (basic fibroblast growth factor or bFGF), crucial for cell maintenance and differentiation. This is especially true when replacing the use of serum that is highly variable, a potential source of microbes or prions, and challenging from ethical and environmental perspectives. Defined Bioscience's introduction of an FGF2 Screening Kit provides researchers with a panel of animal-free, recombinantly expressed FGF2 variants. This kit includes thermostable and native sequences derived from human, bovine/porcine, avian, and piscine sources, enabling a broad spectrum of research applications across vertebrates.

Our recent studies highlight the importance of cross-species FGF2 homologs in stem cell culture efficiency. For instance, FGF2-G3, a variant with nine mutations, has shown remarkable stability and efficacy in promoting cell proliferation, not just in human-derived cells but also in those from other species. The exploration of FGF2 variants across species could uncover sequence variations that impart beneficial characteristics, such as ease of manufacture in recombinant systems, stability in cell culture, and tunable activation of FGF2 receptors. This kit will allow our customers to explore more possibilities in their cell culture systems.  

Our 2022 findings presented at the International Society for Stem Cell Research (ISSCR) conference demonstrate the diverse applications of FGF2 homologs, from human stem cell culture to the field of cultivated meat. Here we recombinantly produced nearly a dozen species homologs of FGF2, purified to >95% from E coli expression systems, and used structural biology approaches to elucidate the three-dimensional structure of FGF2-G3 using x-ray crystallography.

At ISSCR 2023, we continued this work, including functional evaluation in murine 3T3 fibroblast proliferation for select species that indicated differing performance. This work aims to broaden the utility of these growth factors across various life science applications and the cell-cultivated meat industry.

Defined Bioscience’s meticulous validation process of these FGF2 variants, involving functional assays and structural determination, ensures their purity and effectiveness. This rigorous approach not only guarantees high-quality research tools but also fosters confidence in their application across different scientific domains, from basic research to applied biotechnology and agriculture.

In addition to mutant forms of FGF2, surveying FGF2 across several vertebrates allows not only the evaluation of growth factors for use in their own species, but also the evaluation of FGF2 across species where beneficial characteristics might be discovered. Central to the mission of Defined Bioscience, our commercialization of defined, well-characterized growth factors will help advance biomedical research and development.


FGF2 Screening Kit

Defined Bioscience’s FGF2 Screening Kit offers multiple animal-free, recombinantly expressed FGF2 variants for research use. This kit includes four FGF2 variants in easy-to-use aliquots of 10 or 50 µg each, including a combination of thermostable and native sequences from human, cow/pig, chicken, and tuna:

  • FGF2-G3 (human): G3 mutations applied to the native FGF2 sequence for H. sapiens, human (also provided separately as Cat # LSR-101)
  • FGF2-G3 (bovine/porcine): G3 mutations applied to the native FGF2 sequences for B. taurus and S. scrofa, domesticated cattle and pig (also provided separately as Cat # LSR-302)
  • FGF2 (chicken): the native FGF2 sequence for G. gallus, domestic chicken (also provided separately as Cat # LSR-202)
  • FGF2 (tuna): the native FGF2 sequence for T. albacares, yellowfin tuna (also provided separately as Cat # LSR-120)

All factors are recombinantly expressed in E. coli with an N-terminal histidine tag and protease cleavage site. Sample purity is >95%, and all stocks are provided at 1 mg/mL in storage buffer.