Recombinant Human IFN-γ R1

Recombinant Human IFN-γ R1 is primarily used in research as a tool to study and modulate interferon-gamma (IFN-γ) signaling, serving as a high-affinity, species-specific ligand-binding subunit that can act as a decoy or antagonist for IFN-γ in various experimental systems.

Key reasons to use recombinant human IFN-γ R1 in research applications include:

• Functional Antagonist: Soluble recombinant IFN-γ R1 binds IFN-γ with high affinity, effectively sequestering the cytokine and preventing it from interacting with cell-surface receptors. This allows researchers to specifically inhibit IFN-γ-mediated signaling in vitro or in vivo, enabling the study of IFN-γ’s biological roles by observing the effects of its blockade.
• Mechanistic Studies: By blocking IFN-γ signaling, you can dissect the contribution of this pathway to immune responses, inflammation, cell proliferation, apoptosis, and host defense mechanisms. This is particularly useful in models of infection, autoimmunity, cancer, and fibrosis, where IFN-γ plays a central regulatory role.
• Receptor Biology: Recombinant IFN-γ R1 can be used to characterize ligand-receptor interactions, determine binding kinetics, and map functional domains involved in cytokine recognition and receptor activation.
• Assay Development: It serves as a standard or competitor in bioassays designed to measure IFN-γ activity, screen for IFN-γ inhibitors, or validate antibody specificity in blocking IFN-γ signaling.

Technical context:

• IFN-γ R1 is the essential ligand-binding subunit of the IFN-γ receptor complex; it is necessary and sufficient for IFN-γ binding and receptor internalization, while IFN-γ R2 is required for downstream signaling but does not bind IFN-γ independently.
• Recombinant soluble IFN-γ R1 is typically produced as the extracellular domain, which retains high-affinity binding to IFN-γ and is detected in biological fluids as a natural antagonist.
• Human and mouse IFN-γ R1 are only partially homologous and bind IFN-γ in a species-specific manner, so it is important to match the recombinant protein to the species of IFN-γ used in your experiments.

Common applications:

• Blocking IFN-γ activity in cell culture or animal models to study immune regulation, cytokine networks, or disease pathogenesis.
• Investigating the therapeutic potential of IFN-γ antagonism in models of autoimmunity, chronic inflammation, or cytokine storm.
• Validating the specificity of IFN-γ neutralizing antibodies or small-molecule inhibitors.

In summary, recombinant human IFN-γ R1 is a valuable reagent for selectively inhibiting IFN-γ signaling, dissecting cytokine function, and developing assays or therapeutics targeting the IFN-γ pathway.

Recombinant Human IFN-γ R1 (Interferon Gamma Receptor 1) should not be used as a standard for quantification or calibration in ELISA assays designed to measure IFN-γ itself. ELISA standards must match the analyte being quantified; IFN-γ R1 is a receptor protein, not the cytokine IFN-γ.

Supporting details:

• ELISA quantification standards are typically recombinant or purified forms of the analyte of interest—in this case, human IFN-γ—not its receptor. These standards are calibrated against international reference preparations (e.g., NIAID or NIBSC standards) to ensure accurate quantification of IFN-γ concentrations in biological samples.
• Recombinant Human IFN-γ R1 is used as a standard only in ELISA kits specifically designed to measure IFN-γ R1 levels, such as in studies of receptor expression, shedding, or disease biomarker research. It is not interchangeable with IFN-γ for cytokine quantification.
• Using IFN-γ R1 as a standard in an IFN-γ ELISA would result in inaccurate calibration, as the antibodies in IFN-γ ELISA kits are specific for the cytokine, not its receptor.

Best practice:

• For IFN-γ quantification, use a recombinant human IFN-γ protein standard, calibrated against an international reference, as provided or recommended by your ELISA kit manufacturer.
• For IFN-γ R1 quantification, use recombinant IFN-γ R1 as a standard in receptor-specific ELISA kits.

Summary Table:

In conclusion:
Use recombinant human IFN-γ R1 only as a standard for assays measuring IFN-γ R1, not for IFN-γ quantification ELISAs. For IFN-γ ELISA calibration, use recombinant IFN-γ protein standards.

Recombinant Human IFN-γ R1 has been validated primarily for use in bioassays as a soluble receptor and antagonist of IFN-γ signaling in published research. Its main applications include:

• Bioassays: Used to assess its ability to bind IFN-γ with high affinity and antagonize IFN-γ activity in cell-based systems.
• Binding studies: Validated for measuring direct interaction with IFN-γ, confirming its function as a decoy receptor.
• Functional inhibition: Employed to block IFN-γ-mediated cellular responses, such as cytokine signaling, gene expression, and immune activation, in various cell types.

Supporting details:

• The recombinant soluble IFN-γ R1 has been shown to bind IFN-γ with high affinity and act as a potent antagonist, inhibiting IFN-γ-driven biological effects in vitro.
• Published studies have used it to dissect IFN-γ signaling pathways, evaluate the specificity of IFN-γ responses, and explore therapeutic strategies for diseases involving IFN-γ dysregulation.
• It is also referenced in research on heparan sulfate mimicry, where it is used to demonstrate inhibition of IFN-γ activity by synthetic glycoconjugates.

Additional relevant applications (based on broader research use):

• ELISA standard: Recombinant IFN-γ R1 can be used as a standard or control in immunoassays for quantifying IFN-γ or its receptor, though direct published validation for this specific recombinant protein is less frequently cited.
• Cell culture experiments: Used to modulate IFN-γ signaling in cultured cells to study immune responses or disease models.

No evidence was found in the provided results for use in applications such as immunohistochemistry, flow cytometry, or in vivo animal studies for this specific recombinant protein. The most robust validation remains in bioassays and binding/inhibition studies.

To reconstitute and prepare Recombinant Human IFN-γ R1 protein for cell culture experiments, dissolve the lyophilized protein in sterile phosphate-buffered saline (PBS) containing at least 0.1% carrier protein, such as human or bovine serum albumin (HSA or BSA), to a final concentration of 500 μg/mL. This approach minimizes protein loss due to adsorption and stabilizes the protein for downstream applications.

Step-by-step protocol:

• Before opening the vial: Briefly centrifuge the vial to collect all lyophilized material at the bottom.
• Reconstitution: Add sterile PBS (pH 7.2–7.4) containing at least 0.1% carrier protein (HSA or BSA) to achieve the desired concentration (commonly 500 μg/mL for stock solutions).
• Mixing: Gently swirl or tap the vial to dissolve the protein. Avoid vigorous pipetting or vortexing, which may denature the protein.
• Aliquoting: Divide the reconstituted protein into single-use aliquots to avoid repeated freeze-thaw cycles, which can reduce activity and stability.
• Storage: Store aliquots at −20°C or −80°C. Avoid repeated freeze-thaw cycles.

Additional notes:

• If carrier-free protein is required, reconstitute in sterile PBS alone, but use immediately and avoid adsorption to plastic surfaces.
• For cell culture experiments, further dilute the stock solution in cell culture medium or buffer containing carrier protein to the working concentration required for your assay.
• Confirm protein concentration and integrity by SDS-PAGE or other suitable analytical methods if necessary.

Summary of key points:

• Use sterile PBS + 0.1% HSA/BSA for reconstitution.
• Target 500 μg/mL for stock solution.
• Aliquot and freeze to avoid repeated freeze-thaw.
• Gently mix to dissolve, do not vortex.

This protocol ensures optimal stability and bioactivity of recombinant human IFN-γ R1 for cell culture applications.