Recombinant Human FGF R2β (IIIb)

Recombinant Human FGF R2β (IIIb) is a specialized receptor protein that binds fibroblast growth factors (FGFs), particularly those involved in epithelial and tissue regeneration, making it a valuable tool for research in cell signaling, tissue engineering, and disease modeling.

FGF R2β (IIIb) is the epithelial isoform of the fibroblast growth factor receptor 2 (FGFR2), which is critical for mediating FGF signaling in epithelial cells. This isoform specifically interacts with FGF ligands such as FGF-7 and FGF-10, which are key regulators of epithelial cell proliferation, differentiation, and wound healing. Using recombinant FGF R2β (IIIb) allows researchers to:

• Study FGF signaling pathways: By providing a defined receptor, you can dissect the molecular mechanisms of FGF-mediated cellular responses, including proliferation, migration, and differentiation in epithelial tissues.
• Model epithelial tissue development and repair: FGF R2β (IIIb) is essential for understanding processes such as skin regeneration, organoid formation, and mucosal healing, as it mediates the effects of epithelial-specific FGFs.
• Investigate disease mechanisms: Aberrant FGFR2 signaling is implicated in various cancers and developmental disorders. Recombinant FGF R2β (IIIb) enables in vitro studies of receptor-ligand interactions, downstream signaling, and potential therapeutic interventions.
• Biochemical and immunological assays: The recombinant protein, often engineered with tags for stability and purification, serves as a molecular tool for binding studies, receptor-ligand screening, and antibody development.

Advantages of recombinant proteins in research include:

• High purity and bioactivity: Recombinant FGF R2β (IIIb) is produced under controlled conditions, ensuring consistent activity and minimal contaminants.
• Batch-to-batch consistency: This is crucial for reproducibility in experiments, especially in organoid and tissue culture systems.
• Customizability: Recombinant forms can be engineered with tags (e.g., Fc tag) for enhanced stability, detection, and purification, facilitating diverse experimental applications.

In summary, using recombinant Human FGF R2β (IIIb) in your research enables precise investigation of epithelial FGF signaling, supports advanced tissue engineering and disease modeling, and ensures experimental reproducibility and reliability due to its defined molecular properties.

Recombinant Human FGF R2β (IIIb) is a receptor (specifically, a recombinant FGF receptor isoform), not a ligand such as FGF2 (basic FGF or bFGF). Therefore, it is not appropriate to use recombinant Human FGF R2β (IIIb) as a standard for quantification or calibration in ELISA assays designed to measure FGF2 (FGF basic).

Key Points:

• ELISA standards must be the target analyte itself (in this case, FGF2 or bFGF), not its receptor.
• ELISA kits for FGF2 (such as those from Abcam, R&D Systems, or Invitrogen) are calibrated using recombinant human FGF2 protein.
• Using a receptor (FGF R2β) as a standard will not generate a valid standard curve for FGF2, because:
  • The antibody in the ELISA is specific for FGF2, not the receptor.
  • The receptor will not bind in the same way as FGF2 and will not produce a proportional signal.

Correct Approach:

• Use purified or recombinant human FGF2 protein as the standard for FGF2 ELISA assays.
• Many vendors (e.g., Abcam, R&D Systems, Thermo Fisher) provide recombinant human FGF2 specifically for this purpose.

Reference:

• R&D Systems Quantikine ELISA Kit for human FGF basic (FGF2): Calibrated against recombinant human FGF2, not FGF receptor.
• Abcam and other vendors also specify the use of recombinant FGF2 protein for standard curves.

In summary: No, recombinant Human FGF R2β (IIIb) should not be used as a standard for FGF2 ELISA assays. Use recombinant human FGF2 protein instead.

Recombinant Human FGF R2β (IIIb) (also known as FGFR2β or FGFR2 IIIb) has been validated in published research for several key applications, primarily related to its role in cell signaling, tissue development, and disease modeling. Based on the available scientific literature and product characterizations, the following applications have been reported:

1. Biochemical and Molecular Studies:

   • Used as a molecular tool to study fibroblast growth factor (FGF) signaling pathways, particularly interactions between FGF ligands and their receptors.
   • Employed in binding assays to investigate the specificity and affinity of FGF ligands for FGFR2β (IIIb), which is critical for understanding receptor-ligand interactions in development and disease.

2. Cell Culture and Functional Assays:

   • Applied in cell-based assays to study the effects of FGF signaling on cell proliferation, differentiation, and survival, especially in epithelial and mesenchymal cell types.
   • Used to modulate FGF signaling in vitro, for example, by acting as a decoy receptor or by competing with endogenous receptors to block or enhance signaling.

3. Developmental Biology Research:

   • Utilized in studies of embryonic development, particularly in models of organogenesis and tissue patterning, where FGFR2β (IIIb) plays a critical role in epithelial-mesenchymal interactions.

4. Disease Modeling and Therapeutic Target Validation:

   • Employed in research on diseases involving aberrant FGF signaling, such as skeletal dysplasias, cancer, and tissue repair disorders.
   • Used to validate FGFR2 as a therapeutic target, for example, in studies exploring the effects of receptor inhibition or modulation in disease models.

5. Protein-Protein Interaction Studies:

   • Applied in pull-down assays, co-immunoprecipitation, and surface plasmon resonance to characterize interactions between FGFR2β (IIIb) and other proteins or ligands.

6. Immunological and Diagnostic Applications:

   • Used as an antigen in antibody production and immunoassays to detect and quantify FGFR2β (IIIb) expression in tissues or cell lines.

These applications highlight the utility of Recombinant Human FGF R2β (IIIb) as a research reagent for studying FGF signaling, developmental processes, and disease mechanisms. The protein is typically used for research purposes and is not intended for diagnostic or therapeutic use in humans.

Reconstitution Protocol

Initial Preparation

Before opening the vial, centrifuge it in a microcentrifuge for 20-30 seconds to ensure all lyophilized protein is collected at the bottom and not adhered to the cap or vial walls. This step is critical for complete protein recovery.

Reconstitution Buffer and Concentration

Reconstitute the lyophilized FGF R2β (IIIb) protein using sterile phosphate-buffered saline (PBS) containing at least 0.1% human serum albumin or bovine serum albumin. Prepare a stock solution at a concentration of no less than 50 µg/ml. When reconstituting, gently pipette the solution down the sides of the vial rather than using vigorous mixing, vortexing, or aggressive pipetting, as these methods can cause foaming and protein denaturation.

Storage and Stability

Short-term Storage

After reconstitution, store the protein at 2°C to 8°C for up to one month. This refrigerated storage is suitable for immediate experimental use.

Long-term Storage

For extended storage, maintain the lyophilized powder at -20°C to -70°C in a manual defrost freezer, where it remains stable for six to twelve months. Once reconstituted, aliquots can be stored at -20°C to -70°C for up to three months.

Minimizing Freeze-Thaw Cycles

Avoid repeated freeze-thaw cycles, as these significantly compromise protein stability and activity. To prevent this, aliquot the reconstituted solution into smaller portions immediately after preparation, using only what is needed for each experiment. This strategy allows you to thaw individual aliquots without repeatedly exposing the entire stock to temperature fluctuations.

Practical Considerations for Cell Culture

The inclusion of carrier proteins (human or bovine serum albumin) in the reconstitution buffer is essential to prevent protein loss due to adsorption to plastic surfaces and container walls during storage and handling. This is particularly important for growth factors, which are prone to non-specific binding. Maintain sterile conditions throughout all preparation and storage steps to preserve protein integrity and prevent contamination.