Recombinant Mouse IL-18 BPd – Fc

Recombinant Mouse IL-18 BPd – Fc is used in research applications to specifically neutralize and study the biological activity of mouse interleukin-18 (IL-18), a pro-inflammatory cytokine involved in immune regulation, inflammation, and disease models. This fusion protein combines the IL-18 binding protein isoform d (BPd) with an Fc domain, enhancing its stability, solubility, and half-life for in vitro and in vivo studies.

Key reasons to use Recombinant Mouse IL-18 BPd – Fc in research:

• Neutralization of IL-18 Activity: IL-18 BPd acts as a natural antagonist by binding to IL-18 and blocking its interaction with the IL-18 receptor, thereby inhibiting downstream inflammatory responses. This is critical for dissecting the role of IL-18 in immune cell activation, cytokine production, and disease pathogenesis.
• Anti-inflammatory and Immunosuppressive Effects: By neutralizing IL-18, IL-18 BPd – Fc can be used to model or mitigate inflammatory and autoimmune conditions in mouse models, such as colitis, mucositis, or cancer immunology studies.
• Enhanced Pharmacokinetics: The Fc fusion extends the protein’s half-life in circulation, allowing for less frequent dosing and more sustained biological effects in vivo, which is advantageous for chronic or long-term studies.
• Experimental Controls: It serves as a valuable control in assays investigating IL-18-dependent pathways, including ELISA, cell-based bioassays, and in vivo functional studies.
• Mechanistic Studies: Using IL-18 BPd – Fc enables researchers to delineate the specific contributions of IL-18 signaling in immune cell function, cytokine networks, and disease mechanisms, including tumor immunity and inflammatory diseases.

Applications include:

• Inhibition of IL-18-induced T cell and NK cell activation in vitro and in vivo.
• Studying the negative feedback regulation of IL-18 activity, as IL-18 BP expression is upregulated by IFN-γ.
• Modeling therapeutic strategies for IL-18-driven diseases, such as autoimmune disorders, inflammatory bowel disease, and cancer.

Technical advantages:

• The Fc domain improves protein stability, solubility, and ease of purification.
• Recombinant production ensures batch-to-batch consistency and animal-free sourcing.

In summary: Use Recombinant Mouse IL-18 BPd – Fc to specifically block IL-18 activity, investigate its role in immune responses and disease, and as a tool for developing and validating anti-inflammatory or immunomodulatory therapies in mouse models.

Recombinant Mouse IL-18 BPd–Fc can be used as a standard for quantification or calibration in ELISA assays, but only if your assay is specifically designed to detect IL-18 BPd and not IL-18 itself.

Key considerations:

• Target specificity: IL-18 BPd is a binding protein, not the cytokine IL-18. If your ELISA is designed to quantify IL-18 BPd (for example, using a DuoSet ELISA kit for Mouse IL-18 BPd), then recombinant IL-18 BPd–Fc is appropriate as a standard. However, if your assay is for IL-18 (the cytokine), you must use recombinant IL-18 as the standard, not IL-18 BPd.

• Assay validation: Commercial ELISA kits for IL-18 BPd typically use recombinant IL-18 BPd as the standard to generate the calibration curve. The recombinant protein should match the isoform and tag (e.g., Fc fusion) used in your samples for accurate quantification.

• Protein form: Carrier-free or BSA-containing forms can be used, but carrier-free is preferred if BSA may interfere with your assay. Ensure the recombinant standard is of high purity and properly quantified.

• Not interchangeable with IL-18: IL-18 BPd cannot be used as a standard for IL-18 quantification, as they are structurally and functionally distinct proteins.

Summary Table:

Best practices:

• Always match the standard to the analyte your ELISA is designed to detect.
• Confirm that your recombinant standard is validated for use in ELISA and matches the isoform detected by your antibodies.
• Prepare the standard curve according to the kit or protocol instructions for accurate quantification.

If you clarify whether your ELISA is for IL-18 BPd or IL-18, more specific guidance can be provided.

Recombinant Mouse IL-18 BPd–Fc has been validated for several key applications in published research, including bioactivity assays, ELISA controls, and in vivo functional studies.

Validated Applications:

• Bioactivity Assays:
  The protein is routinely used to assess its ability to inhibit IL-18-induced responses in mouse T cells, with reported ED₅₀ values of 0.1–0.4 µg/mL in the presence of recombinant mouse IL-18. This demonstrates its functional capacity to neutralize IL-18 bioactivity in vitro.

• ELISA Control:
  It serves as a standard or control in ELISA assays for quantifying IL-18 or IL-18BP levels in cell culture supernatants.

• In Vivo Functional Studies:
  Published studies have used Recombinant Mouse IL-18 BPd–Fc in mouse models to investigate its effects on immune responses, inflammation, and disease progression. Applications include:

  • Modulation of inflammasome activation and mucositis.
  • Investigation of NK cell receptor signaling and activation thresholds.
  • Suppression of adiponectin expression in adipocytes via IL-18 signaling pathways.
  • Evaluation of antiangiogenic effects in herpetic stromal keratitis.
  • Studies on the efficacy of anticancer chemotherapy and the role of IL-17-producing γδ T cells.

• In Vivo Disease Models:
  The protein has been used to study IL-18’s role in metabolic diseases, cancer immunology, and infectious disease models, often by neutralizing endogenous IL-18 to assess its contribution to pathology or therapeutic response.

• Cell-Based Assays:
  It is validated for use with whole cells and cell culture supernatants to study IL-18 signaling and its inhibition.

Additional Notes:

• The protein’s ability to bind and neutralize IL-18 is dependent on the presence of the complete Ig domain, which is essential for its biological activity.
• Recombinant Mouse IL-18 BPd–Fc is also used as a research tool in autoimmune disease drug development and cytokine regulation studies.
• It is not intended for diagnostic or therapeutic use, but strictly for research applications.

Summary Table of Validated Applications

These applications are supported by multiple peer-reviewed studies and product validation data, confirming the protein’s utility in immunology, inflammation, and metabolic research contexts.

To reconstitute and prepare Recombinant Mouse IL-18 BPd – Fc protein for cell culture experiments, dissolve the lyophilized protein at 100 μg/mL in sterile PBS. Use aseptic technique to avoid contamination.

Essential steps and details:

• Reconstitution:
  Add sterile phosphate-buffered saline (PBS) directly to the lyophilized protein to achieve a final concentration of 100 μg/mL. Gently mix by pipetting or swirling; avoid vigorous agitation to prevent protein denaturation.

• Storage after reconstitution:

  • Store the reconstituted protein at 2–8 °C for up to 1 month under sterile conditions.
  • For longer-term storage, aliquot and freeze at –20 °C to –70 °C in a manual defrost freezer.
  • Avoid repeated freeze-thaw cycles to preserve protein activity.

• Preparation for cell culture:

  • Before use, dilute the stock solution to the desired working concentration in cell culture medium or buffer compatible with your assay.
  • Typical working concentrations for functional assays (e.g., inhibition of IL-18-induced T cell response) range from 0.1–0.4 μg/mL.
  • Ensure the final buffer is compatible with your cell culture system (e.g., PBS without calcium or magnesium, pH 7.2–7.4).

• General best practices:

  • Use sterile, endotoxin-free reagents and containers.
  • Filter the final solution through a 0.2 μm filter if sterility is required and not already ensured by the manufacturer.
  • Prepare aliquots to minimize freeze-thaw cycles.

Summary Table:

Additional notes:

• Confirm the absence of preservatives, calcium, or magnesium in the PBS if your cell culture system is sensitive.
• Always consult the specific product insert for lot-specific instructions.

This protocol ensures optimal solubility, stability, and biological activity of recombinant Mouse IL-18 BPd – Fc protein for cell culture applications.