Recombinant Human SIGIRR

Recombinant human SIGIRR offers significant advantages for research applications due to its well-characterized role as a negative regulator of inflammatory signaling pathways and its therapeutic potential across multiple disease models.

Mechanistic Research Applications

Recombinant SIGIRR enables precise investigation of immune regulation mechanisms. As a transmembrane receptor, SIGIRR functions as a decoy receptor that inhibits signaling through interleukin-1 receptors (IL-1Rs) and Toll-like receptors (TLRs) by interfering with MyD88 dimerization and blocking TRAM homodimer formation. This makes it invaluable for studying how inflammatory pathways are naturally suppressed. You can use recombinant SIGIRR to examine the IL-37/SIGIRR axis, investigate TLR-mediated immune responses, and elucidate the molecular mechanisms underlying immune homeostasis.

Disease Modeling and Therapeutic Development

Recombinant SIGIRR is particularly useful for modeling inflammatory and autoimmune conditions. Research has demonstrated that recombinant human IL-37 exerts therapeutic effects through the IL-1R5/SIGIRR pathway in experimental autoimmune encephalomyelitis models, suggesting applications for multiple sclerosis research. Additionally, SIGIRR dysfunction has been linked to conditions including rheumatoid arthritis, inflammatory bowel disease, and acute respiratory distress syndrome, making recombinant SIGIRR valuable for understanding disease pathogenesis and screening potential interventions.

Functional Assay Development

The protein's specificity and reliability make it suitable for developing robust assays. Recombinant SIGIRR can be used to establish cell-based assays examining TLR and IL-1R signaling inhibition, validate antibodies, and create standardized experimental systems for measuring inflammatory responses. Its precise bioactivity ensures reproducible results across experiments.

Tissue Engineering and Cell Culture Applications

Recombinant signaling proteins like SIGIRR support the development of three-dimensional organoid models and tissue engineering approaches by enabling researchers to manipulate immune microenvironments and study cell-cell interactions in more physiologically relevant contexts.

You can use recombinant human SIGIRR as a standard for quantification or calibration in your ELISA assays, provided it is of high purity and its concentration is accurately determined. Recombinant proteins are commonly used as standards in quantitative ELISA to generate a standard curve, which is essential for determining the concentration of SIGIRR in your samples.

Key considerations:

• Purity and Characterization: The recombinant SIGIRR should be highly purified and well-characterized, ideally with a known concentration determined by reliable methods such as HPLC or absorbance at 280 nm.
• Formulation: Standards are typically supplied lyophilized and should be reconstituted according to the manufacturer’s instructions to ensure consistency and accuracy.
• Standard Curve Preparation: Prepare a fresh set of standards for each assay, covering the expected concentration range of your samples (commonly from low pg/mL to ng/mL, depending on assay sensitivity).
• Matrix Effects: If your samples are in a complex matrix (e.g., serum, plasma), ensure the recombinant standard behaves similarly to endogenous SIGIRR in your assay conditions. Some ELISA kits are validated to recognize both natural and recombinant SIGIRR, which supports the use of recombinant protein as a standard.
• Validation: It is good practice to validate that the recombinant standard yields a parallel response to endogenous SIGIRR in your assay, confirming its suitability for quantification.

Protocol best practices:

• Always prepare and use standards in the same buffer or matrix as your samples to minimize matrix effects.
• Use appropriate curve-fitting models (e.g., 4-parameter logistic regression) for accurate quantification, as ELISA standard curves are typically sigmoidal.
• Discard working standard dilutions after use, as they may not be stable upon storage.

In summary, recombinant human SIGIRR is suitable as a standard for ELISA quantification if it is pure, accurately quantified, and validated for parallelism with endogenous protein in your assay system.

Recombinant Human SIGIRR has been validated in published research for several key applications, primarily in the study of immune regulation, inflammation, and disease models involving Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) signaling pathways.

Validated Applications in Published Research:

• Cellular and Molecular Mechanism Studies:
  Recombinant SIGIRR is widely used to investigate its role as a negative regulator of TLR and IL-1R signaling. Overexpression or exogenous addition of recombinant SIGIRR in cell lines (such as human airway epithelial cells, dendritic cells, and macrophages) has been shown to suppress inflammatory cytokine production (e.g., IL-6, TNF-α) following stimulation with TLR agonists like LPS, flagellin, and CpG DNA. These studies often use recombinant protein to dissect signaling pathways and protein-protein interactions.

• Functional Assays in Immune Modulation:
  Recombinant SIGIRR has been used to demonstrate its ability to inhibit MyD88-dependent signaling, block dimerization of adaptor proteins (such as TRAM), and interfere with downstream activation of NF-κB and mTOR pathways in various immune cell types, including Th17 and NK cells.

• Disease Model Validation:
  In vivo and ex vivo studies have utilized recombinant SIGIRR to explore its therapeutic potential in models of:

  • Autoimmune diseases (e.g., rheumatoid arthritis, experimental autoimmune encephalomyelitis): SIGIRR overexpression or supplementation reduces disease severity and inflammatory responses.
  • Inflammatory diseases (e.g., acute respiratory distress syndrome, non-alcoholic fatty liver disease, necrotizing enterocolitis): Recombinant SIGIRR modulates immune responses and protects against tissue injury.
  • Cancer models (e.g., colon cancer, liver cancer, breast cancer): SIGIRR expression is linked to reduced tumor incidence and progression, and recombinant protein is used to probe these effects.

• Protein Characterization and Biochemical Validation:
  Recombinant SIGIRR is validated for purity and identity by SDS-PAGE and Western blot, and is used as a standard or control in ELISA and other immunoassays.

Summary Table: Applications of Recombinant Human SIGIRR in Research

Key Points:

• Recombinant Human SIGIRR is primarily validated for mechanistic studies of immune regulation, functional assays in immune cells, and as a tool in disease model research.
• It is also used for protein validation and as a standard in immunoassays.
• Its applications are supported by both in vitro and in vivo studies, particularly in the context of inflammation, autoimmunity, and cancer.

If you require details on specific protocols or experimental setups, please specify the context or disease model of interest.

To reconstitute and prepare Recombinant Human SIGIRR protein for cell culture experiments, follow these steps based on best practices and available technical data:

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

2. Reconstitution

   • Use sterile, deionized water or sterile PBS (pH 7.2–7.4) as the solvent, depending on the formulation and downstream application.
   • Typical reconstitution concentration is 0.1–1.0 mg/mL. For example, to achieve 1 mg/mL, add 100 μL of solvent to 0.1 mg of protein.
   • Gently pipette up and down or swirl to dissolve. Avoid vigorous vortexing to prevent protein denaturation.

3. Stabilization (optional but recommended for storage or repeated use)

   • Add glycerol to a final concentration of 5–50% for enhanced stability during storage.
   • For further dilution (especially for cell culture), use PBS containing at least 0.1% BSA to minimize protein adsorption to plastic and maintain activity.

4. Aliquoting and Storage

   • Aliquot the reconstituted protein to avoid repeated freeze-thaw cycles.
   • Store aliquots at –20°C to –80°C for long-term storage. For short-term use (up to 1 month), 2–8°C is acceptable.
   • Avoid repeated freeze-thaw cycles, as this can degrade the protein.

5. Preparation for Cell Culture

   • Before adding to cell culture, dilute the protein to the desired working concentration using cell culture medium or PBS with 0.1% BSA.
   • If endotoxin sensitivity is a concern, confirm the endotoxin level is suitable for your application (typically <1 EU/μg for cell culture).

Summary Table: Key Steps and Conditions

Additional Notes:

• Always consult the specific product datasheet for any unique instructions, as formulations may vary by expression system and purification method.
• If the protein is not carrier-free, be aware of potential additives (e.g., BSA, glycerol) that may affect sensitive assays or cell types.

These steps will help ensure the recombinant SIGIRR protein is properly prepared for reliable use in cell culture experiments.