Recombinant Mouse SIGIRR

Using recombinant Mouse SIGIRR in research applications is valuable for studying the regulation of innate immune signaling, inflammation, and mucosal homeostasis, as SIGIRR is a well-characterized negative regulator of the Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) pathways.

Key scientific reasons to use recombinant Mouse SIGIRR include:

• Dissecting Negative Regulation of Inflammation: SIGIRR attenuates the recruitment of signaling components to TLR4 and interferes with IL-1R1/IL1RAP heterodimerization, thereby suppressing pro-inflammatory signaling cascades. This makes it a critical tool for mechanistic studies on how immune responses are kept in check to prevent excessive inflammation.

• Modeling Disease Mechanisms: Loss or downregulation of SIGIRR is linked to increased susceptibility to inflammatory diseases, autoimmune disorders, and tumorigenesis in mouse models. Recombinant SIGIRR can be used to rescue or modulate these phenotypes in vitro or in vivo, helping to clarify its protective roles.

• Therapeutic Target Validation: Because SIGIRR acts as an anti-inflammatory “brake,” recombinant protein can be used to test therapeutic hypotheses, such as reducing cytokine release or protecting tissues from inflammatory damage in preclinical models.

• Functional Assays and Pathway Analysis: Recombinant SIGIRR enables controlled experiments in cell-based assays to study its effects on TLR/IL-1R signaling, cytokine production, and downstream gene expression, supporting drug screening or pathway dissection.

• Mucosal Immunity and Epithelial Homeostasis: SIGIRR is highly expressed in epithelial and mucosal tissues, where it maintains immune tolerance to commensal microbes and prevents inappropriate inflammation. Recombinant protein can be used to probe these functions in primary cells or organoid systems.

• Genetic and Biochemical Studies: Recombinant SIGIRR provides a defined, species-specific reagent for biochemical assays (e.g., binding studies, structural analysis) and for generating or validating antibodies and detection reagents.

In summary, recombinant Mouse SIGIRR is a critical reagent for investigating the molecular mechanisms of immune regulation, validating therapeutic targets, and modeling disease processes where dysregulated inflammation is central.

Yes, recombinant mouse SIGIRR can be used as a standard for quantification and calibration in ELISA assays, provided you follow proper preparation and validation protocols.

Suitability as an ELISA Standard

Recombinant proteins are well-established standards for ELISA calibration. For recombinant mouse SIGIRR specifically, the protein can serve this function effectively, particularly when you have access to a purified or highly purified preparation. The recombinant protein should be reconstituted according to manufacturer specifications and used to establish your standard curve across an appropriate concentration range, typically 0 to 1000 pg/mL, though this may extend to 3000 pg/mL depending on your target protein concentration predictions.

Important Considerations for Your Assay

Molecular Weight Discrepancy: Be aware that recombinant mouse SIGIRR exhibits an anomalous migration pattern on SDS-PAGE. The predicted molecular weight is approximately 39 kDa, but the protein migrates at approximately 63 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is important to note when validating your assay and interpreting results, as it may indicate post-translational modifications or protein oligomerization.

Antibody Validation: Ensure your detection antibody specifically recognizes mouse SIGIRR without cross-reactivity to related proteins. Validated antibody pairs are available that show no cross-reactivity with recombinant mouse IL-1 R1, IL-1 R2, and other related receptors in direct ELISA formats.

Standard Curve Quality: Your standard curve should yield an R² value greater than 0.99 to ensure reliable quantification. If testing in serum or other biological matrices, include a spike control—a standard diluted in the actual sample matrix—to verify that target protein recovery is acceptable (80–120%).

Preparation Protocol

Reconstitute the recombinant protein according to the manufacturer's instructions, as these may be lot-specific. Maintain proper storage conditions to preserve protein integrity throughout your assay work.

Research Applications and Validation

Recombinant mouse SIGIRR has been validated across multiple research applications, with particular emphasis on its role as a negative regulator of inflammatory signaling pathways.

Immunological and Inflammatory Research

The primary application domain involves studying toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) signaling inhibition. Recombinant mouse SIGIRR has been used to investigate how this protein attenuates recruitment of receptor-proximal signaling components to TLR4 and interferes with IL-1R1 and IL1RAP heterodimerization. Research has demonstrated that ectopic expression of recombinant SIGIRR in human airway epithelial cells leads to reduced transcript levels of inflammatory mediators IL-6 and TNF-α when treated with lipopolysaccharide (LPS), flagellin protein, and CpG DNA.

Disease Model Applications

Autoimmune and neuroinflammatory research represents a significant validated application. In experimental autoimmune encephalomyelitis (EAE) mouse models, recombinant IL-37 activates the SIGIRR pathway to prevent neurofunctional deficits and myelin loss, with no therapeutic effect observed in SIGIRR-deficient mice. Additionally, IL-37 expression has been shown to limit acute and chronic neuroinflammation in the brain and prevent cognitive decline.

Infectious disease research has validated SIGIRR's role in fungal infection models, where signaling through SIGIRR was required to prevent lethal inflammatory pathology associated with disregulated IL-1 responses.

Tissue-Specific and Homeostasis Studies

Recombinant mouse SIGIRR has been applied in research examining intestinal epithelial homeostasis and mucosal immunity. The protein serves as a key regulator of microbial tolerance and maintains epithelial barrier function, making it valuable for studying gut-associated immune responses.

Analytical Techniques

The recombinant protein has been validated for use in Western blot analysis and ELISA applications, enabling quantitative assessment of SIGIRR expression and functional studies in various tissue lysates and cell culture systems.

To reconstitute and prepare Recombinant Mouse SIGIRR protein for cell culture experiments, dissolve the lyophilized protein in sterile PBS (pH 7.2–7.4) or sterile deionized water to a final concentration of 0.1–1.0 mg/mL. Avoid vigorous mixing (such as vortexing) to prevent protein denaturation.

Step-by-step protocol:

1. Briefly centrifuge the vial to collect all lyophilized material at the bottom before opening.
2. Add sterile PBS (pH 7.2–7.4) or sterile deionized water to achieve the desired concentration (typically 0.1–1.0 mg/mL).
3. Gently mix by pipetting up and down or by slow inversion. Do not vortex.
4. If required for stability, add 5–50% glycerol (final concentration) to the solution, especially for long-term storage.
5. Aliquot the reconstituted protein to avoid repeated freeze-thaw cycles.
6. Store aliquots at −20°C to −70°C for long-term use, or at 2–8°C for short-term use (up to one month).
7. For cell culture, dilute the stock solution in cell culture medium or PBS to the working concentration immediately before use.

Additional notes:

• Confirm the absence of endotoxin if using in sensitive cell culture assays.
• If the protein contains tags (e.g., His-tag, GST-tag), verify compatibility with your experimental system.
• Always filter-sterilize the final solution if sterility is critical for your application.

Summary Table: Recombinant Mouse SIGIRR Protein Reconstitution

This protocol ensures optimal solubility and stability for cell culture applications. Always consult the specific product datasheet for any additional manufacturer recommendations regarding buffer composition or additives.