Recombinant Human Glycoprotein 130 (gp130) is a valuable tool for a wide range of research applications due to its central role in cytokine signaling and its broad biological relevance. Here are several key reasons why you should consider using recombinant human gp130 in your research:

1. Central Role in Cytokine Signaling

• gp130 is the shared signal-transducing receptor subunit for multiple interleukin-6 (IL-6)-type cytokines, including IL-6, IL-11, IL-27, leukemia inhibitory factor (LIF), oncostatin M (OSM), cardiotrophin-1 (CT-1), and others.
• It mediates activation of critical downstream signaling pathways such as JAK-STAT, ERK, and PI3K, which regulate immune responses, hematopoiesis, neuronal survival, tissue repair, and more.

2. Versatility in Assay Development

• Recombinant gp130 can be used in bioassays to study cytokine-receptor interactions, signal transduction, and downstream pathway activation.
• It is suitable for functional studies, such as proliferation assays, phosphorylation assays (e.g., STAT3, ERK), and receptor-ligand binding studies.

3. Therapeutic and Disease Relevance

• gp130 signaling is implicated in a variety of diseases, including autoimmune disorders (e.g., rheumatoid arthritis, inflammatory bowel disease), cancer, and chronic inflammation.
• Inhibitors targeting gp130 or its signaling pathways are being developed for therapeutic use, making recombinant gp130 essential for preclinical research and drug screening.

4. Soluble gp130 as a Modulator

• Soluble forms of gp130 (e.g., sgp130Fc) can selectively inhibit IL-6 trans-signaling, a pathway associated with chronic inflammation and tissue damage.
• Recombinant gp130 enables the study of both membrane-bound and soluble receptor functions, providing insights into disease mechanisms and potential therapeutic strategies.

5. Structural and Functional Studies

• Recombinant gp130 is used in structural biology to determine the architecture of cytokine-receptor complexes and to identify functional epitopes.
• It supports the development of antibodies, nanobodies, and other inhibitors targeting gp130 or its ligands.

6. Broad Cellular Expression

• gp130 is expressed in nearly all human tissues, making it relevant for studies across multiple organ systems and disease models.

7. Support for Drug Discovery and Development

• Recombinant gp130 is used in high-throughput screening to identify novel inhibitors or modulators of cytokine signaling.
• It is essential for validating the specificity and efficacy of therapeutic antibodies, nanobodies, and small molecules targeting the IL-6/gp130 pathway.

8. Applications in Inflammation, Autoimmunity, and Cancer Research

• gp130 signaling is a key driver in inflammatory and autoimmune diseases, as well as in tumor progression and immune evasion.
• Using recombinant gp130 allows researchers to dissect these pathways and develop targeted interventions.

In summary, recombinant human gp130 is a versatile and essential reagent for studying cytokine signaling, developing therapeutic strategies, and understanding the molecular basis of inflammation, autoimmunity, and cancer. Its use supports a wide range of experimental approaches, from basic mechanistic studies to translational research and drug discovery.

Using Recombinant gp130 as an ELISA Standard

Based on the available information, recombinant human gp130 would not be suitable as a standard for most commercial ELISA assays designed to measure native gp130. Here's why:

Key Limitation: Detection Specificity

The critical issue is that many gp130 ELISA kits are specifically designed to detect native gp130, not recombinant variants. This distinction is important because:

• Commercial ELISA kits are optimized and validated using native protein standards that match the conformational and post-translational modification state of the target protein in biological samples
• Recombinant proteins often lack the same glycosylation patterns, disulfide bond configurations, and other modifications present in native gp130
• The antibody pairs used in sandwich ELISA assays are selected and validated against specific protein forms

Standard Curve Considerations

ELISA assays require standards that accurately represent the analyte being measured. The standard curve is constructed by plotting absorbance values against known concentrations of a reference material. If you use a recombinant form that differs structurally from the native protein in your samples, the resulting calibration curve may not accurately reflect actual native gp130 concentrations in your biological samples.

Recommended Approach

If you need to use recombinant gp130 in your research:

• Use kit-provided standards: Commercial ELISA kits include validated standard materials specifically formulated for that assay
• Validate cross-reactivity: If you must use recombinant gp130, conduct validation experiments comparing it against native standards to establish any correction factors
• Document your methodology: Clearly specify that recombinant protein was used rather than native protein, as this affects result interpretation

For quantification and calibration purposes, adhering to the kit manufacturer's specified standards ensures accuracy and reproducibility of your ELISA results.

Recombinant Human Glycoprotein 130 (gp130) has been validated for several key applications in published research, primarily centered around its role as a shared signal-transducing receptor for IL-6-type cytokines and its involvement in inflammation, cancer, and tissue homeostasis. The main validated applications include:

1. Inhibition of Cytokine Signaling Pathways
   Recombinant gp130 has been used to study and inhibit signaling by IL-6-type cytokines (including IL-6, IL-11, LIF, OSM, CNTF, CT-1, CLCF1, and IL-27). Soluble forms of gp130 (such as sgp130Fc) have been shown to block IL-6 trans-signaling, which is implicated in chronic inflammation and cancer progression. This inhibition has been validated in models of inflammatory diseases and cancer, including colitis-associated cancer and breast cancer.

2. Therapeutic Development for Inflammatory and Autoimmune Diseases
   Recombinant gp130 and its derivatives (e.g., sgp130Fc) have been validated as potential therapeutics for inflammatory and autoimmune conditions such as rheumatoid arthritis, inflammatory bowel disease, and peritonitis. These agents specifically target the pro-inflammatory trans-signaling pathway of IL-6, offering a more selective approach compared to broad immunosuppression.

3. Cancer Therapy and Tumor Microenvironment Modulation
   Recombinant gp130 has been used to investigate the role of IL-6/gp130 signaling in tumor growth, metastasis, and immune evasion. Studies have demonstrated that blocking gp130 signaling can suppress tumor-promoting inflammation, reduce cancer stem cell renewal, and sensitize tumors to conventional therapies. This has been validated in models of colon, breast, and gastrointestinal cancers.

4. Structural and Functional Studies of Cytokine-Receptor Complexes
   Recombinant gp130 is widely used in structural biology to elucidate the assembly and activation mechanisms of cytokine-receptor complexes, including IL-6 and IL-11 signaling complexes. These studies provide insights into the molecular basis of cytokine signaling and inform the design of targeted inhibitors.

5. Cell-Based Assays and Signal Transduction Research
   Recombinant gp130 is employed in cell-based assays to study downstream signaling pathways such as JAK-STAT, ERK, and PI3K. These assays help characterize the effects of cytokine binding on cell proliferation, survival, and migration, particularly in cancer and immune cell lines.

6. Development of Nanobodies and Single Domain Antibodies (sdAbs)
   Recombinant gp130 has been used as an immunogen to generate camelid-derived nanobodies and sdAbs that specifically inhibit gp130 signaling. These novel inhibitors have shown promise in preclinical models of autoimmunity and cancer.

In summary, recombinant human gp130 has been validated for applications in cytokine signaling inhibition, therapeutic development for inflammatory and oncologic diseases, structural biology, cell-based functional assays, and the generation of targeted biologics such as nanobodies.

To reconstitute and prepare Recombinant Human Glycoprotein 130 (gp130) protein for cell culture experiments, follow these general best practices based on manufacturer protocols and scientific recommendations:

Reconstitution

1. Reconstitution Buffer:

   • Most recombinant human gp130 proteins are lyophilized and should be reconstituted in sterile PBS (pH 7.2–7.4).
   • If the product contains BSA as a carrier protein (check the Certificate of Analysis or product datasheet), reconstitute in sterile PBS containing at least 0.1% human or bovine serum albumin to stabilize the protein.
   • For products without carrier protein, sterile PBS alone is typically sufficient.

2. Reconstitution Concentration:

   • The recommended reconstitution concentration is usually 100 µg/mL.
   • For example, if you have 10 µg of lyophilized protein, add 100 µL of sterile PBS (or PBS + BSA) to achieve 100 µg/mL.

3. Procedure:

   • Centrifuge the vial briefly before opening to ensure all powder is at the bottom.
   • Add the appropriate volume of sterile buffer.
   • Gently swirl or pipette up and down to dissolve the protein. Avoid vigorous shaking to prevent denaturation.
   • Allow the protein to sit for 15–30 minutes at room temperature with gentle agitation to ensure complete reconstitution.

Preparation for Cell Culture

1. Aliquoting:

   • After reconstitution, aliquot the protein into small volumes to avoid repeated freeze-thaw cycles, which can degrade the protein.

2. Storage:

   • For long-term storage, keep aliquots at –20°C or –80°C.
   • If using immediately, store at 4°C for short-term use (up to a few days).

3. Dilution for Cell Culture:

   • Dilute the reconstituted protein in cell culture medium or serum-free medium just before use.
   • The final working concentration depends on your experimental design (e.g., 10–100 ng/mL is common for signaling studies, but optimize based on literature and pilot experiments).

4. Sterility:

   • Ensure all buffers and reagents are sterile to avoid contamination in cell culture.

Additional Tips

• Always refer to the Certificate of Analysis (CoA) or product datasheet for specific instructions, as formulations may vary between suppliers.
• Avoid repeated freeze-thaw cycles to maintain protein activity.
• For functional assays, consider including appropriate controls (e.g., vehicle-only, positive/negative controls).

By following these guidelines, you can ensure proper reconstitution and preparation of recombinant human gp130 protein for reliable and reproducible cell culture experiments.