Recombinant Human IGF-BP7

Recombinant Human IGF-BP7 is used in research applications because it is a multifunctional protein involved in regulating cell proliferation, apoptosis, senescence, angiogenesis, fibrosis, and inflammation, making it a valuable tool for studying diverse biological processes and disease mechanisms.

Key scientific reasons to use recombinant human IGF-BP7 include:

• Cancer Research: IGF-BP7 acts as a tumor suppressor in several cancers by inhibiting tumor cell growth, inducing apoptosis, and suppressing angiogenesis. It modulates cell cycle regulators (e.g., p21, p27), inhibits Akt kinase activity, and can alter cancer cell sensitivity to chemotherapy, making it a candidate for studying tumor biology and potential therapeutic interventions.

• Acute Kidney Injury (AKI) and Fibrosis: IGF-BP7 is a promising biomarker for early detection and prognosis of AKI. It regulates cell cycle arrest, inflammation, fibrosis, and oxidative stress in renal cells, and its modulation can be studied for therapeutic targeting in kidney injury and fibrotic diseases.

• Cardiovascular and Metabolic Research: IGF-BP7 influences cardiac remodeling, senescence, and mitochondrial metabolism in cardiomyocytes. Recombinant IGF-BP7 can be used to model these effects in vitro and in vivo, aiding the study of heart failure, metabolic dysregulation, and potential interventions.

• Angiogenesis and Vascular Biology: IGF-BP7 promotes endothelial cell attachment, vessel stabilization, and maturation during physiological angiogenesis, but can also suppress pathological angiogenesis. Its effects are context-dependent and can be explored in vascular development, tissue remodeling, and disease models.

• Reproductive Biology: IGF-BP7 is involved in folliculogenesis, embryo implantation, and pregnancy outcomes, making it relevant for studies in reproductive physiology and disorders.

• Cellular Senescence and Stem Cell Biology: IGF-BP7 regulates cellular senescence and progenitor/stem cell commitment, providing a tool for investigating aging, tissue regeneration, and stem cell differentiation.

• Mechanistic Studies: Recombinant IGF-BP7 allows for controlled, reproducible experiments to dissect its signaling pathways (e.g., ERK, p38 MAPK, AKT/FOXO3a) and interactions with extracellular matrix components, cytokines, and growth factors.

In summary, using recombinant human IGF-BP7 enables precise investigation of its diverse roles in health and disease, supports biomarker discovery, and facilitates the development of novel therapeutic strategies across oncology, nephrology, cardiology, and regenerative medicine.

Yes, recombinant human IGF-BP7 can be used as a standard for quantification or calibration in ELISA assays, provided it is of high purity and its concentration is accurately known. This is a common practice in quantitative ELISA protocols for IGFBP7, as documented in multiple assay kit protocols and scientific literature.

Key considerations and supporting details:

• Recombinant IGFBP7 as Standard: Many commercial ELISA kits for human IGFBP7 use recombinant human IGFBP7 as the calibration standard to generate the standard curve for quantification. The standard is typically supplied as a lyophilized protein, which is reconstituted and serially diluted to create a range of known concentrations for the assay.

• Purity and Formulation: Ensure the recombinant IGFBP7 is of high purity (preferably >95%) and free from interfering substances such as carrier proteins, unless your assay is validated for such formulations. Carrier-free preparations are generally preferred for standard curve generation.

• Concentration Accuracy: The concentration of the recombinant standard must be precisely determined, as errors here will directly affect the accuracy of your quantification. Use the concentration provided by the manufacturer or determine it using a reliable protein quantification method.

• Assay Compatibility: Confirm that the recombinant IGFBP7 you are using matches the sequence and epitope recognized by the antibodies in your ELISA. Most commercial kits specify the amino acid range of the standard (e.g., D30-L282), which should match your recombinant protein.

• Standard Curve Preparation: Prepare a serial dilution of the recombinant IGFBP7 in the same buffer as your samples or in the diluent recommended by your ELISA protocol. This ensures matrix compatibility and accurate interpolation of sample concentrations.

• Validation: If you are developing your own ELISA or using a non-kit-based approach, validate the performance of your recombinant standard by assessing linearity, recovery, and parallelism with native samples.

Summary Table: Use of Recombinant IGFBP7 as ELISA Standard

In conclusion, recombinant human IGFBP7 is suitable as a standard for ELISA quantification, provided you follow best practices for protein standards and assay validation.

Recombinant Human IGF-BP7 has been validated for several key applications in published research, including ELISA, bioassays, and as a tool for studying cell signaling, biomarker discovery, and disease mechanisms.

Validated Applications in Published Research:

• ELISA (Enzyme-Linked Immunosorbent Assay):

  • Used as a standard for quantifying IGF-BP7 levels in biological samples, including conditioned media from cancer cell lines and in studies of protein-protein interactions (e.g., binding to CCL21/6Ckine).
  • Applied in biomarker studies for diseases such as heart failure and acute kidney injury.

• Bioassays:

  • Functional assays to study IGF-BP7’s effects on cell growth, migration, and interaction with other proteins or cells (e.g., glioma cell growth, leukemia resistance, endothelial cell proliferation).
  • Used to assess IGF-BP7’s role in reciprocal interactions between leukemia cells and bone marrow stromal cells.

• Cell Signaling and Mechanistic Studies:

  • Investigated for its regulatory effects on cell proliferation, apoptosis, migration, and tumor development.
  • Studied in the context of endothelial cell repair, tissue regeneration, and modulation of inflammatory responses.

• Biomarker Validation:

  • Validated as a biomarker for heart failure (especially heart failure with preserved ejection fraction), acute kidney injury, and various cancers.
  • Used in clinical and preclinical studies to correlate IGF-BP7 levels with disease severity, prognosis, and therapeutic response.

• Protein-Protein Interaction Studies:

  • Employed in binding assays to characterize interactions with extracellular matrix proteins (e.g., Type IV collagen) and other signaling molecules.

Additional Context:

• IGF-BP7 has also been used in studies of reproductive biology, fibrosis, metabolic disorders, and tissue regeneration, highlighting its broad utility in both basic and translational research.
• Experimental models include whole cell assays, conditioned media analysis, and in vivo disease models (e.g., heart failure, acute lung injury).

Summary Table:

These applications are supported by multiple peer-reviewed studies and reviews, demonstrating the versatility of recombinant human IGF-BP7 in both experimental and clinical research settings.

To reconstitute and prepare Recombinant Human IGF-BP7 protein for cell culture experiments, dissolve the lyophilized protein in a suitable sterile buffer, typically phosphate-buffered saline (PBS) or sterile distilled water, at a concentration between 0.1–1.0 mg/mL depending on your experimental needs.

Step-by-step protocol:

1. Centrifuge the vial briefly before opening to ensure all lyophilized powder is at the bottom.
2. Add sterile buffer:
   • For most cell culture applications, use sterile PBS or sterile distilled water.
   • Some protocols recommend using a buffer containing 0.1% carrier protein (e.g., BSA) to enhance stability, especially for storage or repeated freeze-thaw cycles.
   • If specified by the manufacturer, you may use 20 mM acetic acid for initial reconstitution, then dilute further in cell culture medium or PBS as needed.
3. Reconstitution concentration:
   • Commonly, reconstitute to 0.1–1.0 mg/mL (e.g., add 100 µL–1 mL buffer per 100 µg protein).
   • Some datasheets specify 500 µg/mL in PBS as a stock concentration.
4. Mix gently:
   • Allow the protein to dissolve at room temperature for 15–30 minutes with gentle agitation. Avoid vigorous shaking or foaming.
5. Aliquot and storage:
   • After reconstitution, aliquot the solution to avoid repeated freeze-thaw cycles.
   • Store aliquots at –20°C to –80°C for long-term use.
   • If using a carrier protein, stability is improved for up to several months at –20°C.
6. Dilution for cell culture:
   • Dilute the reconstituted stock into your cell culture medium to the desired final concentration, typically in the ng/mL to µg/mL range depending on your experimental design.

Additional notes:

• Always consult the specific product datasheet for recommended buffer and concentration, as recombinant protein preparations may differ in formulation and stability requirements.
• Avoid repeated freeze-thaw cycles, as this can denature the protein and reduce activity.
• If your application is sensitive to carrier proteins (e.g., BSA), use a carrier-free preparation and reconstitute in buffer only.

Summary Table:

Always use sterile technique throughout the process to prevent contamination.