Recombinant Human CCL23 (aa 46-137)

Recombinant Human CCL23 (aa 46-137) is widely used in research due to its potent biological activity, especially in studies of immune cell migration, tumor microenvironment modulation, and inflammatory signaling.

Key scientific reasons to use this truncated form (aa 46-137) include:

• Enhanced Biological Activity: The truncated CCL23 (aa 46-137) displays significantly greater biological activity compared to the full-length protein, making it more effective for in vitro and in vivo assays investigating chemotactic responses and signaling pathways.

• Chemotactic Function: CCL23 is a chemokine that induces migration of monocytes, resting T cells, neutrophils, and endothelial cells, but not activated lymphocytes. This makes it valuable for dissecting mechanisms of immune cell recruitment and trafficking in inflammation, infection, and cancer models.

• Tumor Microenvironment Studies: CCL23 plays a dual role in cancer biology. It can contribute to immunosuppression by inducing T-cell exhaustion markers (CTLA-4, PD-1, TIGIT, TIM-3, LAG-3) in CD8+ T cells via GSK3β phosphorylation, relevant for studies on immune checkpoint regulation and tumor immune evasion. Conversely, in hepatocellular carcinoma (HCC), higher CCL23 levels are associated with improved antitumor immunity and better prognosis, suggesting its use in research on tumor suppression and immunotherapy.

• Inflammation and ER Stress: CCL23 modulates inflammatory responses by inhibiting pro-inflammatory cytokines (TNF-α, IL-6, IL-8) and alleviating endoplasmic reticulum (ER) stress, which is important for studies on cellular stress responses and chronic inflammation.

• Matrix Remodeling: CCL23 enhances expression of matrix metalloproteinase-2 (MMP-2) in endothelial cells, implicating it in angiogenesis and tissue remodeling research.

• Biomarker Research: Circulating CCL23 levels are being investigated as biomarkers for acute inflammatory reactions, brain damage, and prognosis in various cancers, making recombinant CCL23 useful for assay development and validation.

Typical applications include:

• Chemotaxis assays for immune cell migration.
• Functional studies of immune checkpoint regulation.
• Tumor microenvironment modeling.
• Investigation of ER stress and inflammatory signaling.
• Angiogenesis and tissue remodeling assays.
• Biomarker validation in disease models.

Best practices: Use the truncated recombinant form (aa 46-137) for optimal activity in cell-based assays, dose-response studies, and mechanistic investigations. Validate purity and bioactivity for reproducibility in experimental protocols.

In summary, Recombinant Human CCL23 (aa 46-137) is a versatile tool for immunology, oncology, and inflammation research due to its enhanced activity and multifaceted roles in immune modulation, cell migration, and tissue remodeling.

You can use recombinant human CCL23 (aa 46-137) as a standard for quantification or calibration in your ELISA assays, provided that the ELISA antibodies recognize this specific fragment and the standard is prepared and validated appropriately.

Key considerations and supporting details:

• Recombinant proteins are commonly used as ELISA standards: Most commercial CCL23 ELISA kits use recombinant CCL23 or synthetic peptides as standards for generating the calibration curve. This is standard practice in quantitative ELISA assays.

• Amino acid sequence compatibility: The fragment you mention (aa 46-137) corresponds to the mature form of human CCL23, which is the biologically active region and is commonly used in both recombinant protein preparations and as ELISA standards. Many commercial kits use similar fragments (e.g., aa 46-137 or aa 46-120) as their standard.

• Antibody recognition: The critical requirement is that the capture and detection antibodies in your ELISA must recognize epitopes within the aa 46-137 region. Most ELISA kits are designed to detect the mature form of CCL23, but you should confirm the epitope mapping in your specific assay documentation or by contacting the antibody supplier.

• Standard preparation: The recombinant protein should be highly pure, accurately quantified, and reconstituted in the same buffer as your samples to ensure reliable standard curves. Serial dilutions should be prepared freshly and used within the recommended time frame to avoid degradation.

• Validation: It is good practice to validate that the standard curve generated with your recombinant CCL23 (aa 46-137) shows parallelism with endogenous CCL23 in your sample matrix, confirming that the assay quantifies both forms equivalently.

Summary Table: Use of Recombinant CCL23 (aa 46-137) as ELISA Standard

Conclusion:
You can use recombinant human CCL23 (aa 46-137) as an ELISA standard if your assay antibodies recognize this region and you follow best practices for standard preparation and validation. Always confirm compatibility with your specific ELISA system.

Recombinant Human CCL23 (aa 46-137) has been validated for use in several key applications in published research, including:

• Blocking Assay
• ELISA (Enzyme-Linked Immunosorbent Assay)
• Functional Assay
• Western Blot

These applications are supported by validation data from reputable sources and are commonly used for studying CCL23's biological activity, quantification, and interaction with its receptor CCR1.

To reconstitute and prepare Recombinant Human CCL23 (aa 46-137) for cell culture experiments, dissolve the lyophilized protein in sterile PBS containing at least 0.1% human or bovine serum albumin (BSA) to a final concentration of 10 μg/mL. Alternatively, some protocols recommend reconstitution at 100 μg/mL in sterile PBS. The presence of carrier protein (such as BSA) is important to prevent adsorption and loss of activity.

Step-by-step protocol:

1. Centrifuge the vial briefly to collect all lyophilized powder at the bottom before opening.
2. Add sterile PBS (phosphate-buffered saline) containing at least 0.1% BSA to the vial to achieve the desired concentration (commonly 10 μg/mL or 100 μg/mL, depending on your application and downstream dilution requirements).
3. Gently mix by pipetting up and down or by gentle vortexing. Avoid vigorous agitation to prevent protein denaturation.
4. Allow the solution to sit at room temperature for 10–30 minutes to ensure complete dissolution.
5. Aliquot the reconstituted protein into small volumes to avoid repeated freeze-thaw cycles.
6. Storage:
   • Store aliquots at 2–8°C for up to one month.
   • For longer-term storage, keep at –20°C to –70°C.
   • Avoid repeated freeze-thaw cycles, as this can reduce protein activity.

Additional notes:

• If your experimental protocol requires a different buffer (e.g., water or a specific cell culture medium), ensure the buffer is sterile and contains a carrier protein such as BSA to stabilize the chemokine.
• For cell-based assays, dilute the reconstituted stock to the working concentration (e.g., 10–50 ng/mL for chemotaxis assays) in cell culture medium immediately before use.
• Always consult the specific product datasheet for any unique instructions or recommendations.

Summary of key points:

• Reconstitute in sterile PBS + 0.1% BSA.
• Typical stock concentration: 10–100 μg/mL.
• Aliquot and store at –20°C to –70°C for long-term use.
• Avoid repeated freeze-thaw cycles.

These steps will help maintain the stability and bioactivity of recombinant CCL23 for cell culture experiments.