Recombinant Human SDF-1β

Recombinant Human SDF-1β (CXCL12β) is a chemokine widely used in research for its ability to regulate cell migration, promote tissue regeneration, modulate immune responses, and influence angiogenesis and fibrosis. Its applications span stem cell biology, tissue engineering, immunology, and disease modeling.

Key scientific reasons to use recombinant SDF-1β in your research:

• Chemotaxis and Cell Migration: SDF-1β binds to the CXCR4 receptor, activating signaling pathways that direct the migration of various cell types, including hematopoietic stem cells, endothelial progenitor cells, and immune cells. This property is essential for studies on stem cell homing, tissue repair, and immune cell trafficking.

• Angiogenesis and Tissue Regeneration: SDF-1β enhances angiogenesis (formation of new blood vessels) and muscle regeneration, particularly in ischemic tissues. It upregulates markers such as VEGF and phosphorylated Akt, facilitating blood flow restoration and tissue repair. This makes it valuable for research in regenerative medicine and vascular biology.

• Wound Healing and Fibrosis Modulation: Recombinant SDF-1β improves wound healing in vitro in a concentration-dependent manner and has demonstrated anti-fibrotic effects in models of lung injury, reducing collagen deposition and improving tissue architecture. These properties are relevant for studies on tissue remodeling and fibrosis.

• Neuroprotection: SDF-1β administration has shown neuroprotective effects, reducing infarct volume and improving neural plasticity in models of cerebral ischemia. This supports its use in neuroscience research, especially in studies of neurodegeneration and brain injury.

• Immunomodulation: SDF-1β regulates lymphopoiesis and enhances survival of myeloid progenitor cells, making it useful for immunology research and studies on hematopoietic stem cell biology.

• Bioassay Utility: Recombinant SDF-1β is used in bioassays to study chemotactic responses, receptor-ligand interactions, and downstream signaling events in various cell types.

Best practices for using recombinant SDF-1β:

• Select appropriate concentrations based on your cell type and application (e.g., 12–120 ng/mL for chemotaxis assays, up to 100 ng/mL for wound healing studies).
• Confirm receptor expression (CXCR4) in your target cells to ensure responsiveness.
• Use carrier-free preparations for sensitive bioassays to avoid interference.

In summary, recombinant human SDF-1β is a versatile tool for investigating cell migration, tissue regeneration, angiogenesis, fibrosis, neuroprotection, and immune cell biology, making it highly relevant for a broad range of biomedical research applications.

Recombinant Human SDF-1β can be used as a standard for quantification or calibration in ELISA assays, provided the assay is designed to detect SDF-1β and the recombinant protein is of appropriate purity and formulation.

Key considerations and supporting details:

• ELISA kits specific for SDF-1β: Several commercial ELISA kits for human SDF-1β use recombinant SDF-1β as the calibration standard, indicating its suitability for quantification in these assays. The standard curve is generated using known concentrations of recombinant SDF-1β, and sample concentrations are interpolated from this curve.

• Assay specificity: It is essential to confirm that your ELISA is specific for the SDF-1β isoform. Some kits are designed for SDF-1α, SDF-1β, or total SDF-1/CXCL12, and cross-reactivity between isoforms can vary. For example, one SDF-1α ELISA reports only 4.4% cross-reactivity with SDF-1β, meaning SDF-1β is not reliably detected in that assay. Always check the assay documentation for cross-reactivity data.

• Standard protein quality: The recombinant SDF-1β used as a standard should be of high purity, preferably carrier-free or with a defined carrier (such as BSA) if compatible with your assay. The protein should be reconstituted and stored according to the manufacturer’s instructions to maintain stability and activity.

• Matrix effects and validation: If you are using a custom or in-house ELISA, validate the recombinant SDF-1β standard in your specific assay matrix (e.g., serum, plasma, cell culture supernatant) to ensure accurate quantification. Recovery and linearity should be assessed by spiking known amounts of the standard into representative samples.

• Documentation and traceability: Record the lot number, concentration, and storage conditions of the recombinant SDF-1β standard for reproducibility and traceability in your experiments.

Summary Table: Use of Recombinant SDF-1β as ELISA Standard

In conclusion: You can use recombinant human SDF-1β as a standard for quantification or calibration in ELISA assays, provided the assay is validated for this isoform and the standard is of suitable quality. Always verify assay compatibility and validate performance in your specific experimental context.

Recombinant Human SDF-1β (CXCL12β) has been validated for several key applications in published research, including chemotaxis assays, functional bioassays, fibrosis models, and tissue engineering.

Validated Applications:

• Chemotaxis Assays: SDF-1β is widely used to induce chemotaxis of various cell types, such as Baf3-hCXCR4 transfectant cells and human peripheral blood lymphocytes, in a dose-dependent manner. This application is central to studies of immune cell migration, stem cell homing, and cancer metastasis.

• Functional Bioassays: The protein is validated for use in bioassays measuring cell survival, proliferation, and autophagy, particularly in bone marrow mesenchymal stem cells. It is also used to study the mobilization of CD34+ progenitors and the regulation of anti-apoptotic pathways.

• Fibrosis Models: Overexpression of SDF-1β has been shown to attenuate fibrosis in bleomycin-injured rat lungs by inducing apoptosis of myofibroblasts, demonstrating its utility in pulmonary fibrosis research.

• Tissue Engineering and Regenerative Medicine: SDF-1β biopatterning on acellular dermal matrix (ADM) has been validated to augment BMP-2-induced osteogenesis, enhancing bone regeneration in tissue engineering applications.

• Inflammation and Immunology: SDF-1β is used to study inflammatory processes in lung, brain, joint, and intestine models, as well as chemotaxis of T, B, and cancer cells.

Additional Notes:

• SDF-1β interacts with the CXCR4 receptor, activating signaling pathways relevant to cell migration, survival, and angiogenesis.
• It is important to distinguish SDF-1β from SDF-1α, as both isoforms have overlapping but distinct biological activities due to their structural differences.
• Recombinant SDF-1β is typically used in research-only applications and is not validated for clinical diagnostics.

Summary Table of Validated Applications

These applications are supported by peer-reviewed studies and product validation data, confirming the utility of recombinant human SDF-1β in diverse experimental contexts.

To reconstitute and prepare Recombinant Human SDF-1β (CXCL12β) for cell culture experiments, follow these steps:

• Centrifuge the vial briefly before opening to ensure all lyophilized protein is at the bottom.
• Reconstitute the protein in sterile deionized water or an appropriate sterile buffer (such as PBS) to a concentration between 0.1–1.0 mg/mL to regain full activity.
• For improved protein stability and to prevent adsorption to plastic, you may add carrier protein (e.g., 0.1% BSA or HSA) to your buffer, especially if you plan to make further dilutions or store aliquots.
• Gently mix (do not vortex vigorously) until the protein is fully dissolved. If the protein appears as a film or does not dissolve immediately, allow it to sit at room temperature for 15–30 minutes with gentle agitation.
• Aliquot the reconstituted protein to avoid repeated freeze-thaw cycles, which can reduce activity.
• Storage: Store aliquots at –20°C or –80°C for long-term storage. For short-term use (up to 1 month), 2–8°C is acceptable under sterile conditions.

Preparation for cell culture:

• Before adding to cell culture, dilute the reconstituted stock to the desired working concentration using sterile cell culture medium or buffer containing carrier protein if needed.
• Filter sterilize if required, especially if the buffer or water used was not sterile.

Summary Table: SDF-1β Reconstitution and Preparation

Additional notes:

• Always consult the specific product datasheet for any unique recommendations.
• Avoid repeated freeze-thaw cycles to maintain protein activity.
• If the protein is difficult to dissolve, allow more time at room temperature or gently pipette up and down.

These steps will ensure optimal activity and stability of SDF-1β for your cell culture experiments.