Recombinant Human Interleukin-8 (IL-8)

Recombinant Human Interleukin-8 (IL-8) is a valuable tool for a wide range of research applications due to its well-characterized biological functions and reproducible activity. Here are several key reasons why you should consider using recombinant human IL-8 in your research:

1. Consistent and Reproducible Activity

Recombinant IL-8 is produced under controlled conditions, ensuring batch-to-batch consistency and high purity. This allows for reliable and reproducible results in experiments, which is critical for both basic research and preclinical studies.

2. Neutrophil Chemotaxis and Activation

IL-8 is a potent chemoattractant for neutrophils and plays a central role in recruiting these cells to sites of inflammation. Using recombinant IL-8 enables researchers to study neutrophil migration, activation, and degranulation in vitro and in vivo, making it essential for immunology and inflammation research.

3. Study of Inflammatory Pathways

IL-8 signals through CXCR1 and CXCR2 receptors, activating downstream pathways involved in inflammation, cell survival, and proliferation. Recombinant IL-8 allows for the investigation of these signaling mechanisms and their roles in diseases such as atherosclerosis, arthritis, and inflammatory bowel disease.

4. Angiogenesis Research

IL-8 promotes angiogenesis by stimulating endothelial cell proliferation and migration. This makes it a useful reagent for studies on tumor neovascularization, wound healing, and ischemic tissue repair.

5. Cancer Biology

IL-8 is implicated in tumor progression, metastasis, and the tumor microenvironment. It can promote epithelial-mesenchymal transition (EMT), recruit immunosuppressive cells, and enhance cancer cell invasiveness. Recombinant IL-8 is therefore widely used in cancer research to model these processes.

6. Functional Assays and Cell Culture

Recombinant IL-8 is optimized for use in cell culture, differentiation studies, and functional assays. It can be used to stimulate primary cells or cell lines, assess cytokine responses, and evaluate the effects of inhibitors or modulators on IL-8-mediated pathways.

7. Disease Modeling and Therapeutic Development

IL-8 is upregulated in various pathological conditions, including acute respiratory distress syndrome (ARDS), myelodysplastic syndrome, and several cancers. Using recombinant IL-8 helps model these disease states and supports the development of targeted therapies.

8. Diagnostic and Prognostic Marker Studies

IL-8 levels are often elevated in patient samples and correlate with disease severity and prognosis. Recombinant IL-8 can be used as a standard in ELISA and other immunoassays to quantify IL-8 in biological samples.

9. Genome Editing and Functional Genomics

Recombinant IL-8 is used in studies involving CRISPR/Cas9 and other genome editing technologies to investigate the functional impact of IL-8 gene polymorphisms and haplotypes on neutrophil function and inflammatory responses.

10. Broad Application Range

Recombinant IL-8 is suitable for a variety of applications, including:

• Chemotaxis assays
• Cell migration and invasion studies
• Angiogenesis assays
• Inflammation and immune response studies
• Cancer biology and tumor microenvironment modeling
• Functional genomics and gene editing

In summary, recombinant human IL-8 is a versatile and essential reagent for researchers studying inflammation, immunity, cancer, angiogenesis, and related fields. Its use ensures precise control over experimental conditions and facilitates the generation of robust, reproducible data.

Yes, you can use Recombinant Human Interleukin-8 (IL-8) as a standard for quantification or calibration in your ELISA assays, provided that the recombinant IL-8 is compatible with the antibodies and detection system used in your specific ELISA kit.

Key Points:

• Standard Use: Recombinant IL-8 is commonly used as a reference standard to generate a standard curve in ELISA assays. This curve allows you to quantify the amount of IL-8 in your samples by comparing their signal to the standard curve.
• Compatibility: Ensure that the recombinant IL-8 standard is recognized by the capture and detection antibodies in your ELISA kit. Most commercial kits are calibrated using recombinant IL-8, often expressed in E. coli.
• Calibration: The standard should be serially diluted in the same matrix as your samples (e.g., assay diluent, buffer, or sample matrix) to create a standard curve. The concentration range of the standard should cover the expected range of IL-8 in your samples.
• Validation: Some kits may specify which form of IL-8 (e.g., 77 aa or 78 aa) is used as the standard. Make sure the recombinant IL-8 you are using matches the form specified by the kit manufacturer for optimal accuracy.

References:

• Many ELISA kits, such as those from R&D Systems, Thermo Fisher, and others, explicitly state that they use recombinant human IL-8 as the standard for calibration.
• The use of recombinant IL-8 as a standard is a standard practice in immunoassays for cytokines like IL-8.

If you are using a commercial ELISA kit, refer to the manufacturer's instructions for specific guidance on the use of recombinant IL-8 as a standard.

Recombinant Human Interleukin-8 (IL-8) has been validated for a broad range of applications in published research, primarily in studies of inflammation, immune cell recruitment, angiogenesis, cancer biology, and as a biomarker in clinical diagnostics.

Validated Applications:

• Functional Assays: IL-8 is widely used to assess its biological activity, such as neutrophil chemotaxis, activation, and degranulation. It is also employed in bioassays to study its effects on various cell types, including endothelial cells, monocytes, and tumor cells.
• ELISA (Enzyme-Linked Immunosorbent Assay): Recombinant IL-8 serves as a standard or control for quantifying IL-8 levels in biological samples, particularly in studies of inflammation, infection, and cancer.
• Western Blot: Used as a positive control for IL-8 detection in protein expression studies.
• Blocking Assays: Applied to investigate the specificity of IL-8-mediated signaling by blocking its interaction with receptors or downstream pathways.
• Immunohistochemistry: Utilized to localize IL-8 in tissue sections, especially in studies of inflammatory or neoplastic lesions.

Research Contexts and Disease Models:

• Neutrophil Chemotaxis and Activation: IL-8 is a prototypical chemoattractant for neutrophils, validated in both in vitro and in vivo migration assays.
• Angiogenesis: IL-8 promotes endothelial cell proliferation and migration, validated in angiogenesis assays and wound healing models.
• Cancer Biology: Used in bioassays to study tumor cell proliferation, metastasis, epithelial-mesenchymal transition (EMT), and resistance to therapies (e.g., EGFR inhibitors).
• Immunomodulation: IL-8 is validated in assays examining recruitment and activation of other immune cells (monocytes, basophils, CD8+ T cells), and its role in immunosuppressive microenvironments.
• Biomarker Studies: IL-8 is validated as a biomarker for diagnosis, prognosis, and monitoring of diseases such as urinary bladder cancer, pulmonary infections, and neonatal bacterial infections.
• Cell Signaling and Pathway Analysis: Used to dissect signaling pathways (e.g., Akt, STAT, ILK) involved in inflammation, cell migration, and tissue remodeling.

Representative Published Research Applications:

• Bioassays for neutrophil migration, monocyte recruitment, and endothelial cell homing.
• ELISA standards for quantifying IL-8 in serum, plasma, or cell culture supernatants in studies of dust exposure, infection, and cancer.
• Functional studies of IL-8-induced apoptosis, chemoresistance, and stemness in tumor cells.
• Imaging: Radiolabeled IL-8 for scintigraphy to visualize infection sites in animal models.
• Gene editing and haplotype analysis to study IL-8 transcriptional regulation and its impact on neutrophil transmigration.

Summary Table of Validated Applications

Key Insights:

• IL-8 is indispensable for neutrophil migration and function, validated in both acute and chronic inflammatory disease models.
• Its role in angiogenesis and cancer progression is supported by functional and bioassay data.
• IL-8 is a clinically relevant biomarker, validated in diagnostic and prognostic studies across multiple medical subspecialties.

These applications are supported by extensive published research, confirming the utility of recombinant human IL-8 in both basic and translational studies.

To reconstitute and prepare Recombinant Human Interleukin-8 (IL-8) for cell culture experiments, follow these best-practice steps:

1. Reconstitution Buffer Selection

• Use sterile phosphate-buffered saline (PBS) or sterile water as the reconstitution buffer. For enhanced protein stability and to minimize adsorption to plastic, add a carrier protein such as 0.1–1% human or bovine serum albumin (HSA/BSA).

2. Reconstitution Concentration

• Commonly, reconstitute the lyophilized IL-8 at 100 μg/mL in your chosen buffer.
• If a different concentration is required for your assay, adjust the volume accordingly, but keep the concentration within 50–100 μg/mL for stock solutions.

3. Reconstitution Procedure

• Briefly centrifuge the vial to collect all lyophilized material at the bottom before opening.
• Add the calculated volume of sterile buffer (with or without carrier protein) directly to the vial.
• Gently mix by pipetting up and down or by slow vortexing. Avoid vigorous agitation to prevent protein denaturation.
• Allow the solution to sit at room temperature for a few minutes to ensure complete dissolution.

4. Aliquoting and Storage

• Aliquot the reconstituted protein into small volumes to avoid repeated freeze-thaw cycles, which can degrade IL-8 activity.
• Store aliquots at –20°C or –80°C for long-term storage. For short-term use (up to one week), store at 2–8°C.
• Avoid multiple freeze-thaw cycles by using single-use aliquots.

5. Working Solution Preparation

• Before adding to cell cultures, dilute the stock solution to the desired working concentration using cell culture medium or sterile PBS with carrier protein if needed.
• Typical working concentrations for cell stimulation range from 0.5–100 ng/mL, depending on the cell type and experimental design.

6. Additional Notes

• If using for ELISA or other quantitative assays, follow the specific protocol for standard preparation, which may involve reconstitution in water and serial dilution in assay buffer.
• Always use sterile technique to prevent contamination.

Summary Table: IL-8 Reconstitution for Cell Culture

These guidelines ensure protein stability, activity, and sterility for reliable cell culture experiments.