Recombinant Rat IL-13

Recombinant Rat IL-13 is used in research applications to model and investigate the biological functions of IL-13, a cytokine central to immune regulation, allergic inflammation, and airway disease in rodent systems.

Key scientific reasons to use recombinant rat IL-13:

• Modeling Allergic and Airway Disease: Recombinant rat IL-13 can induce hallmark features of allergic inflammation, such as eosinophilia, mucus hypersecretion, and airway hyperresponsiveness in rodent models. This is essential for studying the mechanisms of asthma and evaluating potential therapeutics targeting IL-13 signaling.

• Immunological Studies: IL-13 modulates immune cell function, including suppressing proinflammatory cytokine production by macrophages and promoting immunoglobulin class switching in B cells. Recombinant protein enables controlled in vitro and in vivo experiments to dissect these pathways.

• Neuroimmune Research: IL-13 has neuromodulatory effects, such as regulating dopaminergic neuron activity and influencing reward-related behaviors. Recombinant rat IL-13 allows for precise manipulation in neurobiology studies.

• Cell Culture and Bioassays: Recombinant rat IL-13 is used as a standard or stimulant in cell-based assays, ELISA, and Western blotting to quantify responses or validate antibody specificity.

• Therapeutic Target Validation: By administering recombinant IL-13, researchers can assess the efficacy of neutralizing antibodies, siRNAs, or receptor antagonists in preclinical models, supporting drug development for asthma, COPD, and other inflammatory diseases.

Technical advantages of recombinant rat IL-13:

• High Purity and Bioactivity: Recombinant rat IL-13 is typically produced in yeast or baculoviral systems, ensuring proper folding and post-translational modifications for reliable biological activity.
• Carrier-Free and Endotoxin-Free: The protein is supplied without carrier proteins or endotoxins, minimizing experimental artifacts and ensuring compatibility with sensitive assays.
• Consistent Molecular Weight: The recombinant form maintains a precise molecular weight (∼13.3 kDa), supporting reproducibility in quantitative applications.

Typical applications include:

• Inducing or blocking IL-13-mediated responses in rodent models of allergy, asthma, and inflammation.
• Investigating IL-13’s role in immune cell differentiation, cytokine signaling, and tissue remodeling.
• Validating therapeutic strategies targeting IL-13 or its receptors.

Using recombinant rat IL-13 is essential for mechanistic studies, assay development, and preclinical validation in immunology, allergy, and neuroimmune research, where rodent models are the standard experimental system.

Yes, recombinant rat IL-13 can generally be used as a standard for quantification or calibration in ELISA assays, provided it is of high purity, properly reconstituted, and validated for this purpose. The recombinant rat IL-13 protein is specifically described as suitable for use as an ELISA standard, with high purity (>95%), carrier-free formulation, and consistent molecular weight, which are all critical for reliable quantification.

Key considerations and best practices:

• Purity and Formulation: The recombinant rat IL-13 described is >95% pure, lyophilized, and carrier-free, making it appropriate for use as a standard in ELISA assays.
• Reconstitution: It should be reconstituted in sterile phosphate-buffered saline (PBS) containing at least 0.1% carrier protein (such as BSA) to maintain stability and prevent adsorption to plasticware.
• Validation: While recombinant IL-13 is commonly used as a standard in commercial rat IL-13 ELISA kits, it is essential to ensure that the standard curve generated with your recombinant protein is parallel to the curve generated with the kit’s supplied standard, if applicable. This ensures comparable quantification.
• Bioactivity and Structure: Recombinant proteins expressed in eukaryotic systems (such as yeast) are more likely to have correct folding and post-translational modifications, supporting their use as standards.
• Documentation: Always refer to the ELISA kit’s protocol to confirm compatibility. Some kits specify that only their supplied standard should be used for calibration, as differences in protein folding or glycosylation can affect antibody recognition.

Limitations and caveats:

• Kit-Specific Requirements: Some ELISA kits may require the use of their proprietary standard for optimal accuracy, due to differences in antibody specificity or protein conformation. Always check the kit documentation.
• Matrix Effects: If you are quantifying IL-13 in complex matrices (e.g., serum, plasma), ensure that the recombinant standard behaves similarly to endogenous IL-13 in your assay system. This can be checked by performing spike-and-recovery and parallelism experiments.

Summary Table: Use of Recombinant Rat IL-13 as ELISA Standard

In conclusion: You can use recombinant rat IL-13 as a standard for ELISA quantification if it is of high purity and properly reconstituted, but always validate its performance in your specific assay and confirm compatibility with your ELISA kit.

Recombinant Rat IL-13 has been validated for several key applications in published research, primarily in the context of immunology and allergy studies. The most commonly validated applications include:

• Bioactivity assays: Used to confirm the protein’s ability to elicit a biological response, such as stimulating cell proliferation or signaling pathways in vitro.
• ELISA standard: Employed as a quantitative standard in enzyme-linked immunosorbent assays to measure IL-13 levels in biological samples.
• Western blot control: Used as a positive control to verify antibody specificity and protein detection in Western blotting experiments.
• Binding assays: Utilized to study interactions between IL-13 and its receptors or neutralizing antibodies.
• Neutralization assays: Applied to assess the efficacy of neutralizing antibodies or inhibitors targeting IL-13 activity.

Additional context and supporting details:

• Recombinant rat IL-13 is widely used in cell culture experiments to stimulate cells and study downstream effects, particularly in models of allergic inflammation and immune regulation.
• The protein has been used to generate neutralizing antisera in animal models, which is valuable for functional studies and immunization protocols.
• Its role in immunology and allergy research is well established, especially for investigating mechanisms of asthma, atopy, and tissue inflammation.
• The protein is typically validated for bioactivity using cell proliferation assays (e.g., with TF-1 cells) and for use as a standard in quantitative immunoassays.

Summary Table: Validated Applications for Recombinant Rat IL-13

These applications are supported by both vendor validation and published research, with bioactivity and immunoassay use being the most frequently cited.

To reconstitute and prepare Recombinant Rat IL-13 protein for cell culture experiments, dissolve the lyophilized protein in sterile phosphate-buffered saline (PBS) containing at least 0.1% carrier protein, such as Bovine Serum Albumin (BSA), or directly in your complete cell culture medium if it contains serum. This ensures protein stability and bioactivity for downstream applications.

Step-by-step protocol:

• Equilibrate the vial to room temperature before opening to minimize condensation.
• Centrifuge the vial briefly to collect the lyophilized powder at the bottom.
• Add sterile PBS with 0.1% BSA (or your cell culture medium with serum) to the vial. The recommended concentration for reconstitution is typically 10 μg/mL, but you may adjust based on your experimental needs.
• Mix gently by pipetting up and down or by gentle vortexing until fully dissolved. Avoid vigorous agitation to prevent protein denaturation.
• Aliquot the solution to avoid repeated freeze-thaw cycles, which can degrade the protein.
• Store reconstituted protein at −20°C for up to 3 months. For short-term use (2–7 days), store at 4–8°C.

Additional notes:

• If using for cell stimulation, you may reconstitute directly in your cell culture medium (e.g., DMEM with 10% FBS), as this provides sufficient carrier protein for stability.
• Always use sterile technique to prevent contamination.
• The final concentration of carrier protein should be at least 0.1%; higher concentrations (up to 1–10%) can be used if additional stability is required.
• Avoid repeated freeze/thaw cycles by aliquoting into single-use volumes.

Example calculation:If you have a 5 μg vial and reconstitute in 100 μL PBS + 0.1% BSA, your stock concentration will be 50 μg/mL.

Summary of best practices:

• Use sterile PBS + 0.1% BSA or cell culture medium with serum.
• Gentle mixing and aliquoting are essential.
• Store at −20°C and avoid freeze/thaw cycles.

These steps will ensure optimal stability and bioactivity of recombinant rat IL-13 for cell culture experiments.