Recombinant Human IL-13 Rα1

Recombinant Human IL-13 Rα1 is a valuable research tool for studying the molecular mechanisms of IL-13 signaling, receptor-ligand interactions, and the functional roles of the IL-13 receptor complex in immunology, inflammation, and disease models.

Key scientific applications and rationale include:

• Receptor-Ligand Interaction Studies: Recombinant IL-13 Rα1 enables precise analysis of how IL-13 binds to its receptor, both alone and in combination with IL-4Rα, forming the high-affinity receptor complex that activates downstream signaling pathways such as JAK1/STAT6. This is essential for dissecting the molecular basis of cytokine signaling and receptor cooperativity.

• Functional Assays: Using recombinant IL-13 Rα1 allows you to reconstitute or block IL-13 signaling in cell-based assays, helping to elucidate its role in processes like alternative macrophage activation, inhibition of IFN-γ-induced gene expression, and modulation of immune responses. This is particularly relevant for studying type 2 immunity, allergic inflammation, and fibrosis.

• Therapeutic Target Validation: IL-13 Rα1 is highly expressed in various disease contexts, such as asthma, ulcerative colitis, and certain cancers (e.g., diffuse intrinsic pontine glioma). Recombinant protein can be used to screen for neutralizing antibodies, small molecules, or engineered ligands that modulate receptor activity, supporting drug discovery and immunotherapy development.

• Decoy and Soluble Receptor Studies: Soluble forms of IL-13 Rα1 can act as decoy receptors, regulating IL-13 bioavailability and downstream effects, such as glucose metabolism and immune modulation. Recombinant protein enables mechanistic studies of these regulatory pathways.

• Biochemical and Structural Analysis: Recombinant IL-13 Rα1 is essential for in vitro binding assays, crystallography, and biophysical characterization, providing insights into receptor structure, affinity, and complex stability.

Best practices:

• Use recombinant IL-13 Rα1 in combination with IL-13 and/or IL-4Rα to model physiological receptor complexes.
• Employ in cell-based assays to study signaling, gene expression, and functional outcomes.
• Apply in screening platforms for therapeutic antibody or antagonist development.

In summary, recombinant human IL-13 Rα1 is indispensable for mechanistic, functional, and translational research on IL-13 biology, immune regulation, and therapeutic targeting.

Recombinant Human IL-13 Rα1 can be used as a standard for quantification or calibration in ELISA assays specifically designed to detect IL-13 Rα1, but not for assays targeting IL-13 itself.

For ELISA assays that measure IL-13 Rα1 (the receptor subunit), recombinant human IL-13 Rα1 is suitable as a standard, as these assays are validated to recognize both recombinant and naturally produced forms of the protein. The standard curve generated with recombinant IL-13 Rα1 allows accurate quantification of this receptor in biological samples.

However, if your ELISA is designed to quantify IL-13 cytokine (not the receptor), you must use recombinant human IL-13 as the standard, since the assay antibodies are specific to IL-13 and do not recognize IL-13 Rα1. Using IL-13 Rα1 as a standard in an IL-13 assay would yield inaccurate results due to lack of cross-reactivity.

Best practices for ELISA calibration:

• Always match the standard protein to the target analyte of your assay (IL-13 Rα1 for receptor assays, IL-13 for cytokine assays).
• Confirm that your ELISA kit or protocol is validated for recombinant standards and check for any cross-reactivity or interference issues in the kit documentation.
• Prepare the standard curve according to the manufacturer’s instructions, using serial dilutions of the recombinant protein in the recommended diluent.

Summary Table:

If you are quantifying IL-13 Rα1, you may proceed with recombinant human IL-13 Rα1 as your standard. For IL-13 quantification, use recombinant human IL-13 instead. Always verify your assay’s specificity and validation details before proceeding.

Recombinant Human IL-13 Rα1 has been validated for several applications in published research, primarily in the context of immunology, cell signaling, and therapeutic target studies.

Key validated applications include:

• ELISA (Enzyme-Linked Immunosorbent Assay): Used as a standard or capture reagent to quantify IL-13 or to study IL-13/IL-13Rα1 interactions.
• Western Blot: Employed to detect IL-13Rα1 protein expression in cell or tissue lysates.
• 3D Cell Culture: Utilized in advanced cell culture models to study receptor-ligand interactions and downstream signaling.
• Cell and Gene Therapy Research: Investigated as a target or component in studies aiming to modulate immune responses or develop therapeutic interventions.
• Cell-based Functional Assays: Used to study IL-13 signaling, including activation of JAK/STAT pathways and cellular responses to IL-13 stimulation.
• Immunohistochemistry: Applied to detect IL-13Rα1 expression in tissue samples, such as in studies of diffuse intrinsic pontine glioma (DIPG).
• Therapeutic Target Validation: Explored as a target for monoclonal antibodies (e.g., tralokinumab) in clinical research for diseases like atopic dermatitis and ulcerative colitis, where blocking IL-13/IL-13Rα1 interaction is therapeutically relevant.

Supporting details:

• Recombinant IL-13 Rα1 is often used to reconstitute receptor complexes in vitro to study IL-13 and IL-4 signaling, including JAK1, STAT3, and STAT6 activation.
• It is also used in metabolic research, such as studies on adipogenesis and glucose metabolism, by examining the effects of IL-13/IL-13Rα1 signaling in preadipocytes.
• In immunological studies, recombinant IL-13 Rα1 helps characterize T cell subsets and their regulatory roles, particularly in autoimmune models like NOD mice.

Summary of main validated applications:

• ELISA
• Western blot
• Cell-based signaling and functional assays
• Immunohistochemistry
• 3D cell culture
• Therapeutic antibody validation
• Metabolic and immunological research models

These applications are supported by both product datasheets and primary research literature, reflecting the broad utility of recombinant human IL-13 Rα1 in basic and translational research.

To properly reconstitute and prepare Recombinant Human IL-13 Rα1 protein for cell culture experiments, follow these general best practices based on manufacturer protocols and scientific recommendations:

Reconstitution Protocol

1. Centrifuge the Vial
   Before opening, briefly centrifuge the lyophilized protein vial in a microcentrifuge (20–30 seconds) to ensure all powder is at the bottom.

2. Reconstitution Solution
   Reconstitute the protein in sterile, endotoxin-free distilled water (ddH₂O) or sterile PBS (phosphate-buffered saline), depending on the manufacturer’s instructions.

   • Typical recommended concentration: 0.1–0.5 mg/mL (some protocols suggest up to 1 mg/mL).
   • For example, for 100 µg of protein, add 100–500 µL of sterile water or PBS.

3. Gentle Mixing

   • Gently pipette the solution down the sides of the vial.
   • Do not vortex or mix vigorously to avoid denaturation or aggregation.

4. Allow Complete Dissolution
   Let the vial sit at room temperature for several minutes to ensure complete reconstitution.

Preparation for Cell Culture

• Aliquot and Store

  • Aliquot the reconstituted protein into small volumes to avoid repeated freeze-thaw cycles.
  • For short-term storage (≤1 month), keep at 2–8°C.
  • For long-term storage, freeze at –20°C to –80°C (preferably –80°C for maximum stability).

• Carrier Protein (Optional)
  For prolonged storage, consider adding a carrier protein such as 0.1% BSA (bovine serum albumin) or 0.1% HSA (human serum albumin) to prevent adsorption and loss of activity.

Additional Notes

• Avoid Repeated Freeze-Thaw Cycles
  Repeated freezing and thawing can reduce protein activity and stability.

• Check Manufacturer’s Instructions
  Always refer to the specific Certificate of Analysis (CoA) or product insert for lot-specific recommendations, as formulations may vary (e.g., presence of tags, buffer composition).

Summary

• Centrifuge vial before opening.
• Reconstitute in sterile ddH₂O or PBS to 0.1–0.5 mg/mL.
• Gently mix; do not vortex.
• Aliquot and store at –20°C to –80°C.
• Add 0.1% BSA/HSA for long-term storage if desired.
• Avoid repeated freeze-thaw cycles.

These steps will help maintain the activity and integrity of Recombinant Human IL-13 Rα1 for reliable results in cell culture experiments.