Technote | FGF-8b (Qk057) bioactivity
Qkine fibroblast growth factor 8b (FGF-8b) bioactivity is comparable to an alternative supplier protein
Fibroblast growth factor 8b (FGF-8b) is a spliced form of FGF–8, a member of the FGF family. FGFs regulate many developmental and cellular processes including proliferation, survival, angiogenesis and tumorigenesis. It is involved in the regulation of embryogenesis and is commonly used for the differentiation of induced pluripotent stem cells (iPSC) into neural cell types and for brain organoid cultures.
Qkine FGF-8b (Qk057) is animal origin-free (AOF), carrier protein-free, tag-free and non-glycosylated to ensure high and consistent bioactivity.
Qkine FGF-8b bioactivity
- FGF-8b (Qk057) was bioactive in a quantitative luciferase assay with EC50 of 5.9 ng/ml.
- This was comparable to FGF-8b from an alternative supplier, which had an EC50 of 6.5 ng/ml.
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Qkine FGF-8b bioactivity was comparable to FGF-8b from an alternative major supplier. HEK293T luciferase reporter cells were treated in triplicate with a serial dilution of Qkine FGF-8b (Qk057, green) or Peprotech FGF-8b (100-25, Supplier B, black) for 3 hours. Protein concentrations were corrected for vial recovery before use (Peprotech vial recovery 88%, Qkine 97%). Firefly luciferase activity was measured and normalized to control Renilla luciferase activity. Data from Qk004 lot #204523.
Qkine recombinant proteins have the advantage of being highly pure and animal origin-free, giving lot-to-lot consistency in bioactivity for long-term reproducible culture of stem cells and organoids.