Recombinant Human FGF R2β (IIIc)

Recombinant Human FGF R2β (IIIc) is a valuable tool in research because it enables precise investigation of fibroblast growth factor (FGF) signaling, particularly in studies of cell proliferation, differentiation, tissue regeneration, and disease modeling. This recombinant receptor provides high specificity, reproducibility, and functional activity, making it suitable for a range of experimental applications.

Key reasons to use Recombinant Human FGF R2β (IIIc) in research:

• FGF Signaling Studies: FGF receptors, including the R2β (IIIc) isoform, mediate cellular responses to FGFs, which are critical for processes such as development, wound healing, angiogenesis, and tissue repair. Using the recombinant receptor allows you to dissect the specific roles of FGF2 and related ligands in these pathways.

• Functional Assays: Recombinant FGF R2β (IIIc) can be used in cell-based assays to study ligand-receptor interactions, receptor activation, and downstream signaling events. For example, it is measured by its ability to inhibit FGF-dependent proliferation in certain cell lines, providing a direct readout of receptor function.

• Protein-Protein Interaction Studies: The recombinant receptor, especially when fused to tags (e.g., Fc or His), facilitates biochemical assays such as pulldown, ELISA, or surface plasmon resonance to characterize binding affinities and kinetics with FGFs or other interacting proteins.

• Therapeutic and Regenerative Research: FGF signaling is implicated in nerve regeneration, bone formation, and tissue repair. Recombinant FGF receptors are used to model these processes in vitro and in vivo, enabling the development and testing of new therapeutic strategies.

• Batch Consistency and Purity: Recombinant proteins offer superior batch-to-batch consistency and purity compared to native or partially purified proteins, ensuring reproducibility and reliability in experimental results.

• Customization for Experimental Needs: Recombinant FGF R2β (IIIc) can be engineered with specific tags or modifications to suit different assay formats or detection methods, increasing experimental flexibility.

Applications include:

• Ligand binding and competition assays
• Signal transduction pathway analysis
• Screening for FGF pathway inhibitors or activators
• Organoid and stem cell culture systems requiring defined growth factor signaling
• Disease modeling for cancer, developmental disorders, and tissue regeneration

Summary:
Using recombinant human FGF R2β (IIIc) enables controlled, reproducible, and mechanistically precise studies of FGF signaling, which is essential for advancing understanding in developmental biology, regenerative medicine, and therapeutic research.

Recombinant Human FGF R2β (IIIc) is not suitable as a standard for quantification or calibration in ELISA assays designed to measure FGF2 (basic FGF); it is a receptor protein, not the ligand. ELISA standards must match the analyte being quantified, both in structure and immunoreactivity.

Essential context:

• ELISA quantification requires a standard curve generated from the same analyte as the target in your samples. For FGF2 quantification, the standard should be purified or recombinant human FGF2 (basic FGF), not its receptor.
• FGF R2β (IIIc) is a splice variant of the fibroblast growth factor receptor 2, not FGF2 itself. Using the receptor as a standard would not yield accurate or meaningful quantification of FGF2, as antibodies in FGF2 ELISA kits are specific for the ligand, not the receptor.
• ELISA kits for FGF2 are calibrated using recombinant human FGF2, and validation data show parallelism between recombinant and natural FGF2 curves, confirming suitability for quantification. There is no evidence that FGF R2β (IIIc) can substitute for FGF2 in these assays.

Best practices for ELISA standards:

• Use purified or recombinant protein identical to the analyte for standard curve preparation.
• Confirm that the standard is recognized by the assay antibodies and produces a linear, parallel dose-response curve with your samples.
• Do not substitute related proteins, isoforms, or receptors unless the assay documentation explicitly validates their use as standards.

Additional relevant information:

• If you wish to quantify FGF R2β (IIIc) itself, you would need an ELISA specifically designed for that receptor, with standards consisting of recombinant FGF R2β (IIIc).
• Using mismatched standards (e.g., receptor for ligand quantification) can lead to inaccurate results and invalidate assay calibration.

Summary Table:

Conclusion:
For ELISA quantification of FGF2, use recombinant or purified FGF2 as your standard. Recombinant FGF R2β (IIIc) cannot be used as a standard for FGF2 quantification in ELISA assays.

Recombinant Human FGF R2β (IIIc) has been validated in published research primarily for applications involving its role as a decoy receptor or antagonist in studies of fibroblast growth factor (FGF) signaling, particularly in the context of cancer and bone disease models.

Key validated applications include:

• Therapeutic Targeting in Cancer: FGFR2IIIc (the isoform corresponding to FGF R2β (IIIc)) has been studied as a therapeutic target in colorectal carcinoma. Research has examined its expression and functional roles, with the aim of evaluating the effectiveness of FGFR2IIIc-targeted therapies. This involves using recombinant FGFR2β (IIIc) to probe signaling pathways and test inhibitors or neutralizing agents.

• Decoy Receptor in FGF2 Signaling Studies: Recombinant human FGFR2β (IIIc)-Fc fusion proteins have been used as soluble decoy receptors to sequester FGF2, thereby inhibiting FGF2-mediated signaling. This approach has been validated in studies investigating the effects of FGF2 on cell proliferation, differentiation, and disease progression, including bone remodeling and joint disease models. In these studies, the recombinant protein is used to block FGF2 activity and assess downstream effects such as ERK1/2 phosphorylation and cell proliferation.

• In Vitro Functional Assays: The recombinant protein has been used in cell-based assays to study FGF2-dependent cellular responses, such as proliferation of endothelial cells and osteosarcoma cells, by acting as a competitive inhibitor of FGF2 binding to its native receptors.

Summary Table: Validated Research Applications

Additional Context:

• The recombinant FGFR2β (IIIc) is typically used as an Fc-fusion protein, enhancing its stability and facilitating its use in binding and neutralization assays.
• While FGF2 (the ligand) is widely studied for tissue regeneration and wound healing, the receptor isoform FGFR2β (IIIc) is specifically validated for applications involving modulation or inhibition of FGF2 signaling, rather than direct regenerative effects.

No published research was found validating this recombinant protein for direct use in tissue engineering, wound healing, or regenerative medicine applications; such applications are more commonly associated with FGF2 itself rather than its receptor isoforms.

To reconstitute and prepare Recombinant Human FGF R2β (IIIc) protein for cell culture experiments, follow these steps to ensure protein integrity and biological activity:

• Centrifuge the vial briefly (10–30 seconds in a microcentrifuge) before opening to collect all lyophilized material at the bottom.
• Reconstitute the protein in sterile phosphate-buffered saline (PBS) to a final concentration of 0.5 mg/mL. If your application requires a different concentration, adjust accordingly using sterile PBS.
• Gently mix the solution by pipetting up and down or gentle inversion. Avoid vigorous vortexing, which can denature the protein.
• For enhanced stability, especially if the protein will be stored in solution or used at low concentrations, consider adding a carrier protein such as 0.1–0.5% BSA (bovine serum albumin) to the PBS. This helps prevent adsorption to tube walls and loss of activity.
• Aliquot the reconstituted protein into single-use volumes to avoid repeated freeze-thaw cycles, which can degrade the protein.
• Storage after reconstitution:
  • Short-term (up to 1 month): Store at 2–8 °C.
  • Long-term: Store at –20 °C to –70 °C in a manual defrost freezer.
  • Avoid repeated freeze-thaw cycles to maintain activity.

Additional notes:

• Always consult the lot-specific Certificate of Analysis (COA) or datasheet for any unique instructions or recommended diluents, as formulations can vary between lots and suppliers.
• If using the protein in cell culture, ensure all solutions are sterile and handle under aseptic conditions.
• If the protein is fused to Fc or other tags, confirm compatibility with your downstream assays or cell types.

Summary protocol:

1. Centrifuge vial, open aseptically.
2. Add sterile PBS (with or without 0.1–0.5% BSA) to achieve 0.5 mg/mL.
3. Mix gently until fully dissolved.
4. Aliquot and store at –20 °C to –70 °C for long-term use; 2–8 °C for short-term.
5. Avoid repeated freeze-thaw cycles.

These steps will help maintain the integrity and activity of Recombinant Human FGF R2β (IIIc) for reliable cell culture experiments.