Recombinant Human CD120b (TNFR2) (aa 24-206)

Recombinant Human CD120b (TNFR2) (aa 24-206) is widely used in research because it represents the extracellular domain of the human TNFR2 receptor, which is critical for studying TNF-α signaling, immune regulation, and therapeutic targeting in diseases such as cancer and autoimmune disorders.

Key reasons to use this protein in research applications:

• Functional Studies of TNF-α Signaling: TNFR2 (CD120b) is a primary receptor for membrane-bound TNF-α, mediating diverse biological processes including immune cell activation, proliferation, apoptosis, and inflammation. Using the recombinant extracellular domain (aa 24-206) allows you to study ligand binding, receptor activation, and downstream signaling events in a controlled, cell-free system.

• Immunology and Cancer Research: TNFR2 is highly expressed on regulatory T cells (Tregs) and some tumor cells, where it plays a key role in immunosuppression and tumor immune evasion. Recombinant TNFR2 can be used to:

  • Investigate Treg biology and their suppressive mechanisms.
  • Screen or characterize antibodies, antagonists, or agonists targeting TNFR2 for immunotherapy development.
  • Model the tumor microenvironment and study immune checkpoint pathways.

• Soluble Receptor Studies: The aa 24-206 fragment corresponds to the soluble extracellular domain (sTNFR2), which naturally occurs in vivo and can neutralize TNF-α activity. This makes it valuable for:

  • ELISA and other binding assays to quantify TNF-α or test neutralization.
  • Studying the regulation and function of soluble TNFR2 in inflammation and autoimmunity.

• Protein Engineering and Structural Biology: The recombinant form is suitable for:

  • Structural studies (e.g., crystallography, NMR) to elucidate ligand-receptor interactions.
  • Generating immunogens for antibody production or epitope mapping.

• Assay Development: Recombinant TNFR2 (aa 24-206) is commonly used as a standard or capture reagent in bioactivity assays, Western blotting, and SDS-PAGE, due to its high purity and defined sequence.

Technical considerations:

• The protein is typically expressed in mammalian cells to ensure proper folding and post-translational modifications.
• It is supplied in a lyophilized form for stability and ease of storage, with high purity (>95%) and low endotoxin levels, making it suitable for sensitive assays.

In summary, Recombinant Human CD120b (TNFR2) (aa 24-206) is a versatile tool for dissecting TNF-α/TNFR2 biology, developing immunotherapies, and creating robust immunological assays, especially where the extracellular domain’s interactions are of primary interest.

You can use Recombinant Human CD120b (TNFR2) (aa 24-206) as a standard for quantification or calibration in ELISA assays, provided it is highly purified and its concentration is accurately determined.

For ELISA quantification, the standard should be:

• Purified recombinant protein: Your protein is reported as >95% pure by SDS-PAGE and silver stain, which is suitable for use as a standard.
• Low endotoxin: The endotoxin level (<0.1 EU/µg) is appropriate for most immunoassays.
• Known concentration: You must accurately determine the concentration of your recombinant TNFR2, typically using absorbance at 280 nm or a protein assay, to prepare a reliable standard curve.
• Relevant sequence: The aa 24-206 fragment covers the extracellular domain commonly used in soluble TNFR2 ELISAs, making it suitable for calibration if your assay detects this region.

Best practices for ELISA standard preparation:

• Prepare serial dilutions of the recombinant protein in the same buffer as your samples to minimize matrix effects.
• Run a standard curve with each assay plate to ensure accurate quantification.
• Confirm that your assay antibodies recognize the same epitope(s) present in the recombinant fragment (aa 24-206) to avoid calibration errors.

Limitations and considerations:

• If your ELISA is designed to detect full-length or differently processed TNFR2, confirm that the aa 24-206 fragment matches the epitope recognized by your antibodies.
• Recombinant standards may differ in glycosylation or folding compared to native proteins, which can affect antibody binding and quantification. Validate recovery and parallelism with native samples if possible.

In summary, Recombinant Human CD120b (TNFR2) (aa 24-206) is suitable as an ELISA standard if it matches the assay’s detection region, is highly pure, and its concentration is precisely known. Always validate the standard curve and assay performance with control samples.

Based on the provided search results, the Recombinant Human CD120b (TNFR2) (aa 24-206) has been validated for the following applications in published research or manufacturer documentation:

• ELISA
• Immunogen
• SDS-PAGE
• Western Blot (WB)
• Bioactivity testing (in progress, as noted in the product description)

These applications are listed for the recombinant protein (Catalog No. EHD38903) expressed in mammalian cells, with the protein fragment spanning amino acids 24-206. The information is sourced from AntibodySystem.com (result ).

To reconstitute and prepare Recombinant Human CD120b (TNFR2) (aa 24-206) protein for cell culture experiments, follow these steps:

• Centrifuge the vial briefly to ensure all lyophilized protein is at the bottom before opening.
• Reconstitute the protein in sterile distilled water or sterile PBS (pH 7.2–7.4), depending on the formulation. For most protocols, a concentration of 0.1–0.5 mg/mL is recommended. Some sources specify at least 100 μg/mL as a minimum concentration for initial reconstitution.
• Avoid vigorous mixing: Do not vortex or pipette aggressively, as this can denature the protein.
• Add a carrier protein or stabilizer if the protein will be stored or used at low concentrations. Common stabilizers include 0.1% BSA, 5% HSA, 10% FBS, or 5% trehalose. Carrier proteins help prevent adsorption to tube walls and increase stability, especially for cell culture applications.
• Aliquot the reconstituted solution to minimize freeze-thaw cycles, which can degrade the protein.
• Storage after reconstitution: Store aliquots at –20°C to –80°C for long-term stability. For short-term use, aliquots can be kept at 2–8°C for up to several weeks.
• Dilute to working concentration in cell culture medium or assay buffer immediately before use. Ensure the final buffer is compatible with your cell culture system (e.g., serum-free or serum-containing medium).

Summary Table: Reconstitution Protocol

Additional Notes:

• Always consult the specific Certificate of Analysis (CoA) or datasheet for your batch for any manufacturer-specific instructions.
• If using for cell culture, ensure all reagents are sterile and endotoxin levels are appropriate for your application.
• For bioactivity assays, confirm the protein’s activity post-reconstitution if required.

This protocol ensures optimal solubility, stability, and biological activity of recombinant TNFR2 for cell culture experiments.