Recombinant Human FGF-8f

Recombinant Human FGF-8f is used in research applications because it is a potent, well-characterized growth factor that plays essential roles in cell proliferation, differentiation, migration, and tissue development, particularly in embryogenesis and organogenesis. Its recombinant form ensures high purity, batch-to-batch consistency, and reliable bioactivity, which are critical for reproducible experimental results.

Key scientific reasons to use recombinant human FGF-8f include:

• Developmental Biology: FGF-8 isoforms, including FGF-8f, are crucial for normal development of the eye, ear, brain, and limb, and regulate processes such as gastrulation and epithelial-mesenchymal transitions. FGF-8f is specifically recognized for its role in androgen-dependent growth and mammary gland development.
• Cellular Functions: FGF-8f promotes cell proliferation, differentiation, and migration, making it valuable for studies involving stem cells, tissue engineering, and regenerative medicine.
• Cancer and Disease Models: Overexpression of FGF-8 isoforms has been linked to increased tumor growth and angiogenesis, making recombinant FGF-8f useful for modeling cancer biology and testing anti-angiogenic therapies.
• Organoid and 3D Culture Systems: Recombinant growth factors like FGF-8f are preferred in organoid research due to their superior bioactivity, low endotoxin levels, and absence of animal-derived contaminants, which are essential for maintaining physiological relevance and experimental reproducibility.
• Defined, Animal-Free Reagents: Recombinant FGF-8f is produced in controlled systems, ensuring high purity and low endotoxin content, which minimizes variability and unwanted immune responses in sensitive cell culture systems.

Best practices for using recombinant FGF-8f:

• Use in chemically defined, serum-free media to support stem cell maintenance, differentiation, or organoid growth.
• Validate activity in your specific assay system, as optimal concentrations may vary depending on cell type and application.
• Store and handle according to manufacturer recommendations to preserve bioactivity and stability.

In summary, recombinant human FGF-8f is a scientifically validated tool for studying developmental processes, disease mechanisms, and regenerative therapies, offering high reproducibility and experimental control compared to native or animal-derived growth factors.

Yes, recombinant human FGF-8f protein can be used as a standard for quantification and calibration in ELISA assays, though there are important considerations for optimal results.

Suitability as an ELISA Standard

Recombinant FGF-8f is well-suited for ELISA applications because it provides a defined, reproducible reference material. The protein is typically produced in E. coli and supplied in a lyophilized format with high purity (95% by SDS-PAGE under reducing conditions), ensuring consistency across experiments. The molecular weight of approximately 25.5 kDa is well-characterized, allowing for accurate concentration calculations and standardization.

Key Advantages

High bioactivity and lot-to-lot consistency are critical features of recombinant FGF-8f preparations. Extensive quality control ensures that results are reproducible and reliable across different batches. This consistency is essential when using the protein as a calibration standard, as variability between lots would compromise the accuracy of your quantification.

Structural integrity is maintained in the lyophilized formulation, which typically includes stabilizing components such as carrier proteins (BSA), buffering agents (MOPS), and reducing agents (DTT). This formulation preserves the protein's ability to be recognized by antibodies in sandwich ELISA formats.

Practical Considerations

When using recombinant FGF-8f as an ELISA standard, reconstitute the lyophilized protein according to manufacturer specifications. After reconstitution, the protein remains stable for approximately 1 month at 2-8°C under sterile conditions, or 3 months when stored at ≤-20°C. Prepare serial dilutions in an appropriate buffer containing carrier protein (such as 0.1% BSA) to maintain protein stability and prevent non-specific adsorption to tube surfaces.

Important Limitation

One critical caveat: recombinant standards used for ELISA calibration may not be suitable for bioassay applications where biological activity is being measured. If your downstream work requires assessment of FGF-8f bioactivity, you should verify that your standard has been specifically validated for functional assays rather than relying solely on immunoassay calibration.

Applications of Recombinant Human FGF-8f

Recombinant Human FGF-8f has been validated for bioactivity applications in research contexts. This protein functions as a secreted heparin-binding growth factor and is utilized in studies examining fibroblast growth factor signaling pathways.

Research Context and Related Applications

While specific published research applications for FGF-8f are limited in the provided literature, the broader FGF-8 family has demonstrated utility in several research areas:

Stem Cell Differentiation and Proliferation

FGF-8 isoforms, including FGF-8f, are employed in studies involving neural stem cells, embryonic stem cells, and induced pluripotent stem cells. The FGF-8 family's role in developmental biology makes these proteins valuable for investigating cell fate determination and differentiation pathways.

Developmental Biology Studies

FGF-8 signaling has been extensively characterized in limb morphogenesis and developmental processes. The protein's involvement in midbrain and cerebellar development provides a foundation for its use in developmental research applications.

Receptor Signaling Research

FGF-8f, like other FGF-8 isoforms, activates fibroblast growth factor receptors (FGFR1, FGFR2, FGFR3, and FGFR4), making it suitable for investigating receptor-ligand interactions and downstream signaling cascades.

The primary validated application remains bioactivity assays, where the protein's ability to stimulate cellular responses through FGF receptor activation can be measured and characterized in controlled experimental systems.

To reconstitute and prepare Recombinant Human FGF-8f protein for cell culture experiments, dissolve the lyophilized protein in sterile buffer—typically sterile PBS or water—at a concentration of 0.1–0.5 mg/mL, then dilute further as needed for your assay. Addition of a carrier protein such as 0.1% endotoxin-free recombinant human serum albumin (HSA) or bovine serum albumin (BSA) is recommended to stabilize the protein and minimize adsorption to surfaces.

Step-by-step protocol:

• Preparation:

  • Briefly centrifuge the vial to collect the powder at the bottom before opening.
  • Use aseptic technique throughout.

• Reconstitution:

  • Add sterile PBS (pH 7.2–7.4) or sterile water to achieve a final concentration of 0.1–0.5 mg/mL.
  • If recommended, include 0.1% carrier protein (HSA or BSA) in the buffer.
  • Gently swirl or tap the vial to mix; avoid vigorous shaking or foaming.
  • If the protein forms a film, gently mix until fully dissolved.

• Aliquoting and Storage:

  • Once fully dissolved, aliquot the solution to minimize freeze-thaw cycles.
  • Store aliquots at −20°C to −70°C for long-term use; at 2–8°C for short-term (up to 1 month).
  • Avoid repeated freeze-thaw cycles to preserve bioactivity.

• Working Solution:

  • Dilute the stock solution in cell culture medium immediately before use.
  • Typical working concentrations for cell culture range from 1–100 ng/mL, depending on cell type and experimental design.

Additional notes:

• Always consult the product-specific Certificate of Analysis (CoA) or data sheet for precise instructions, as buffer composition and recommended concentrations may vary by manufacturer and isoform.
• For FGF-8 isoforms, including FGF-8f, the buffer may contain stabilizing agents such as MOPS, EDTA, DTT, and sodium sulfate; ensure compatibility with your cell culture system.
• If using for sensitive applications, confirm endotoxin levels are suitable for your cell type.

Summary Table:

This protocol ensures optimal solubility, stability, and bioactivity of recombinant FGF-8f for cell culture experiments.