Recombinant Human FGF-5

Recombinant Human FGF-5 (Fibroblast Growth Factor-5) is a valuable tool for research applications due to its well-characterized biological activities and regulatory roles in multiple cellular processes. Here are key reasons to use Recombinant Human FGF-5 in your research:

1. Regulation of Cell Proliferation and Differentiation

• FGF-5 promotes both cell proliferation and differentiation by binding to FGF receptors 1 and 2 (FGFR1 and FGFR2), making it useful for studies involving cell growth, survival, and lineage specification.
• It is particularly important in skeletal muscle development, where it regulates myoblast differentiation and migration.

2. Role in Angiogenesis

• FGF-5 enhances angiogenic potential in endothelial cells, especially in human aortic endothelial cells (HAECs), supporting vascular sprouting and vessel formation.
• This makes it suitable for research on vascular biology, tissue engineering, and regenerative medicine.

3. Involvement in Cancer Biology

• FGF-5 is expressed in melanoma and other cancers, where it enhances tumor growth, proliferation, and angiogenesis.
• Studies show that FGF-5 overexpression increases tumor growth and reduces apoptosis in xenograft models, while silencing FGF-5 reduces clonogenicity and tumor progression.
• It is a target for tumor-suppressive microRNAs and is linked to signaling pathways such as MAPK and NFAT, but not STAT3.

4. Neurotrophic and Developmental Functions

• FGF-5 acts as a survival factor for spinal motoneurons and plays a role in embryonic development, particularly in the myotomes and lateral somatic mesoderm.
• It is involved in postnatal muscle maintenance and neurobiology.

5. Hair Growth and Alopecia Research

• FGF-5 is implicated in hair elongation and has been associated with androgenetic alopecia, making it relevant for dermatological and cosmetic research.

6. Standardized and Reproducible Results

• Recombinant Human FGF-5 provides a consistent, purified source of the protein, ensuring reproducibility in experimental outcomes compared to endogenous or crude extracts.

7. Versatile Applications

• Suitable for a wide range of assays, including:
  • Cell proliferation and differentiation assays
  • Angiogenesis models (e.g., 3D microfluidic systems)
  • Cancer cell line studies (proliferation, apoptosis, clonogenicity)
  • Neurobiology and developmental biology research
  • Wound healing and tissue regeneration studies

8. Compatibility with Functional Assays

• Can be used in combination with siRNA, inhibitors, or other growth factors to dissect signaling pathways and cellular responses.

In summary, Recombinant Human FGF-5 is a powerful reagent for investigating cell growth, differentiation, angiogenesis, cancer progression, neurobiology, and hair biology, offering reliable and reproducible results across diverse research fields.

Yes, recombinant human FGF-5 can generally be used as a standard for quantification or calibration in ELISA assays, provided it matches the sequence and conformation recognized by the antibodies in your specific ELISA kit. Many commercial FGF-5 ELISA kits use recombinant human FGF-5 as their standard, and the assay is designed to detect both natural and recombinant forms.

Key considerations for using recombinant FGF-5 as an ELISA standard:

• Sequence and Structure: The recombinant FGF-5 should have the same amino acid sequence and post-translational modifications (if relevant) as the native protein detected by your ELISA antibodies. Most kits specify that their standards are recombinant proteins, and the antibodies are validated to recognize both natural and recombinant FGF-5.
• Purity and Activity: Ensure the recombinant protein is of high purity (typically >90–95% by SDS-PAGE) and retains its native conformation, as ELISA detection depends on epitope integrity.
• Carrier Proteins: Some recombinant FGF-5 preparations contain carrier proteins like BSA to enhance stability. If your ELISA is sensitive to BSA or other additives, use a carrier-free preparation.
• Calibration Curve Preparation: Accurately reconstitute and dilute the recombinant FGF-5 according to your ELISA kit’s instructions to generate a reliable standard curve.
• Validation: If you are substituting the kit’s supplied standard with your own recombinant FGF-5, validate that the standard curve generated is comparable in sensitivity and linearity to the kit standard. This ensures accurate quantification.

Summary Table: Considerations for Using Recombinant FGF-5 as an ELISA Standard

In summary: Recombinant human FGF-5 is widely used as a standard in ELISA kits for quantification and calibration, but you must ensure compatibility with your specific assay and validate performance if substituting for the kit’s standard.

Recombinant Human FGF-5 has been validated for several key applications in published research, primarily in bioassays assessing cell proliferation, differentiation, migration, and angiogenesis, as well as in studies of hair growth regulation, tumor biology, and neurobiology.

Validated Applications:

• Cell Proliferation and Differentiation Assays:
  Recombinant FGF-5 has been used to stimulate proliferation in fibroblasts, endothelial cells, and osteosarcoma cell lines, as well as to promote differentiation in skeletal muscle and neural stem cell models.

• Angiogenesis Assays:
  FGF-5 has been validated in 3D microfluidic angiogenesis systems and endothelial cell sprouting assays, demonstrating its role in promoting vessel formation and vascular density.

• Neurobiology and Motoneuron Survival:
  It has been used as a survival factor for cultured spinal motoneurons and to study Schwann cell migration and adhesion, implicating FGF-5 in neural development and repair.

• Hair Growth Regulation:
  FGF-5 is a crucial regulator of hair length in humans, and recombinant protein has been used in both in vitro and in vivo models to study hair follicle cycling and elongation.

• Tumor Biology and Malignancy:
  Recombinant FGF-5 has been applied in clonogenic assays, siRNA knockdown experiments, and xenotransplantation models to investigate its role in melanoma, hepatocellular carcinoma, and other cancers.

• Cell Migration and Adhesion:
  Studies have shown FGF-5 promotes rapid Schwann cell migration and adhesion via upregulation of N-cadherin.

• Receptor Activation and Signal Transduction:
  FGF-5 has been validated for binding and activating FGF receptors (FGFR1 and FGFR2) in receptor autophosphorylation assays.

Common Experimental Formats:

• Whole cell bioassays (proliferation, differentiation, migration)
• 3D microfluidic angiogenesis systems
• Clonogenic assays (colony formation)
• In vivo xenotransplantation models
• Immunohistochemistry (IHC) and siRNA knockdown
• ELISA and Western blot as standards or controls

Sample Types:

• Whole cells (fibroblasts, endothelial cells, neural cells, tumor cells)
• Whole tissue (hair follicles, tumor xenografts)

Summary Table:

In summary: Recombinant Human FGF-5 is a versatile research reagent validated for bioassays in cell proliferation, differentiation, angiogenesis, neurobiology, hair growth, tumor biology, migration, and receptor activation, using a variety of cell and tissue models in published studies.

To reconstitute and prepare Recombinant Human FGF-5 protein for cell culture experiments, first check whether your protein is supplied lyophilized or in solution, and whether it contains a carrier protein. The following protocol is based on best practices and multiple authoritative sources:

1. Centrifuge the vial:
Briefly centrifuge the vial before opening to ensure all lyophilized material is at the bottom.

2. Reconstitution:

• For most lyophilized FGF-5 preparations, reconstitute with sterile water to a concentration of 0.1 mg/mL (100 μg/mL).
• Some protocols recommend reconstituting in sterile PBS containing 1 μg/mL sodium heparin and at least 0.1% human or bovine serum albumin (BSA/HSA) to enhance stability and prevent adsorption to plastic. This is especially important if the protein is carrier-free or will be stored at low concentrations.

3. Gentle mixing:
Gently pipette up and down or swirl to dissolve the protein completely. Avoid vigorous vortexing to prevent denaturation.

4. Aliquoting:
Aliquot the reconstituted protein into small volumes to avoid repeated freeze-thaw cycles, which can reduce activity.

5. Storage:

• Short-term: Store at 4°C and use within 1 month.
• Long-term: Store aliquots at −20°C to −80°C for up to 3 months or longer. Avoid repeated freeze-thaw cycles.

6. Working solution preparation:
For cell culture, dilute the stock solution to the desired working concentration using cell culture medium or buffer containing at least 0.1% BSA or HSA to minimize protein loss due to adsorption.

7. Heparin supplementation:
FGF-5, like other FGFs, may require heparin for optimal biological activity and stability in cell culture. Add sodium heparin to a final concentration of 1 μg/mL if not already included in your reconstitution buffer.

Summary Table: FGF-5 Reconstitution Protocol

Notes:

• Always consult the specific product datasheet for any manufacturer-specific recommendations, as buffer composition and protein stability may vary.
• If using for sensitive cell types, ensure endotoxin levels are appropriate for your application.

This protocol ensures optimal solubility, stability, and bioactivity of recombinant human FGF-5 for cell culture experiments.