Recombinant Human Contactin-1

Recombinant Human Contactin-1 is used in research applications to study its roles in neural development, cell adhesion, cancer biology, and neurodegenerative diseases, as well as to model its molecular interactions and test therapeutic strategies.

Key scientific reasons to use Recombinant Human Contactin-1:

• Neuroscience and Cell Biology: Contactin-1 is a cell adhesion molecule critical for the formation and maintenance of paranodal domains in myelinated nerve fibers, influencing saltatory conduction and axo-glial signaling. Recombinant protein enables controlled studies of its structure, function, and interactions, such as with neurofascin 155, which are essential for nervous system wiring and myelination.

• Disease Modeling: Dysfunction or altered expression of Contactin-1 is implicated in neuropsychiatric disorders, neurodevelopmental syndromes, demyelinating neuropathies, and neurodegenerative diseases (e.g., Alzheimer’s, Parkinson’s). Recombinant Contactin-1 allows for in vitro and in vivo modeling of these conditions, facilitating mechanistic studies and biomarker validation.

• Cancer Research: Contactin-1 (CNTN1) is dysregulated in various carcinomas and is associated with cancer cell invasion, metastasis, and chemoresistance, particularly through epithelial-mesenchymal transition (EMT) and activation of pathways such as PI3K/AKT. Recombinant protein is essential for functional assays, drug screening, and pathway analysis in cancer biology.

• Immunology and Autoimmunity: Contactin-1 is a specific antigen in certain immune-mediated demyelinating neuropathies, making recombinant protein valuable for developing diagnostic assays and studying autoimmune mechanisms.

• Experimental Applications: Recombinant Contactin-1 is suitable for use as an immunogen, protein standard, in cell culture, and other cell biology applications where precise control over protein concentration, purity, and modifications is required.

Best practices for use:

• Select the appropriate recombinant format (e.g., full-length, domain-specific, tagged) based on your experimental needs.
• Use carrier-free preparations for ELISA or binding assays, and BSA-containing formulations for cell culture to maintain protein stability.
• Confirm bioactivity and purity for functional studies, as some preparations may be untested or partial fragments.

Summary: Recombinant Human Contactin-1 is a versatile tool for dissecting its molecular functions in neural and cancer biology, modeling disease mechanisms, and developing diagnostic or therapeutic strategies. Its use enables reproducible, mechanistic research that cannot be achieved with endogenous protein alone.

Yes, you can use recombinant human Contactin-1 as a standard for quantification or calibration in ELISA assays, provided it is properly purified and its concentration is accurately determined. Recombinant proteins are commonly used as standards in quantitative ELISA protocols when native protein standards are unavailable or impractical.

Key considerations for using recombinant Contactin-1 as an ELISA standard:

• Purity and Quantification: The recombinant protein should be highly purified, and its concentration must be precisely measured, typically by absorbance at 280 nm, BCA assay, or HPLC.
• Standard Curve Preparation: Prepare a serial dilution of the recombinant Contactin-1 in the same buffer or diluent used for your samples to generate a standard curve covering the expected concentration range in your assay.
• Matrix Effects: Ideally, dilute the recombinant standard in a matrix similar to your samples (e.g., serum, plasma, or cell culture medium) to minimize matrix effects and ensure comparable binding and detection.
• Validation: Confirm that the recombinant protein is recognized equivalently by the ELISA antibodies compared to the native protein. Some ELISA kits are optimized for native proteins and may show different reactivity to recombinant forms, especially if post-translational modifications differ.
• Documentation: Follow best practices for ELISA standard curve setup, including duplicate or triplicate wells for each standard point, and ensure all pipetting steps are consistent.

Scientific best practice:

• Recombinant proteins are widely accepted as ELISA standards when native proteins are unavailable, as long as the recombinant form is structurally and immunologically similar to the native protein.
• Some commercial ELISA kits include recombinant Contactin-1 as their calibrator, indicating suitability for quantitative calibration.

Limitations:

• If your ELISA kit is specifically designed to detect only native Contactin-1, confirm with the kit documentation or by a pilot experiment that the recombinant standard is detected equivalently.
• Always ensure the recombinant protein is free of contaminants that could interfere with antibody binding or signal generation.

Summary Table: Recombinant Contactin-1 as ELISA Standard

In conclusion:
Recombinant human Contactin-1 is suitable as a standard for ELISA quantification if it meets the above criteria and is validated for your specific assay system.

Recombinant Human Contactin-1 has been validated in published research for several key applications, primarily in studies of cell signaling, neurobiology, immunology, and cancer biology.

Validated Applications in Published Research:

• Protein–Protein Interaction Studies:
  Recombinant Contactin-1 has been used in structural and biophysical assays to characterize its interaction with neurofascin 155, including cell-clustering assays, surface plasmon resonance, and analytical ultracentrifugation to study oligomerization and binding affinities. These studies elucidate the molecular basis of axo-glial junction formation and myelin maintenance.

• Cellular Functional Assays:
  Overexpression and transfection of recombinant Contactin-1 in cell lines (e.g., HEK293, A549) have been used to investigate its role in innate immune signaling, specifically its regulation of the RIG-I/MAVS pathway and type I interferon response during viral infection. Functional assays include:

  • Reporter gene assays for IFN-β promoter activity
  • ELISA for interferon quantification
  • Immunoblotting for pathway protein expression and phosphorylation
  • Co-immunoprecipitation and pull-down assays to confirm direct protein interactions

• Immunogen and Protein Standard:
  Recombinant Contactin-1 is recommended as an immunogen for antibody production and as a protein standard in immunoassays such as Western blotting and ELISA. These uses are foundational for generating and validating detection reagents.

• Cell Culture and Cell Biology Applications:
  The protein is used in cell culture to study cell adhesion, signaling, and differentiation, particularly in neural and cancer cell models. It is also applied in assays investigating the effects of Contactin-1 on cell migration, proliferation, and signaling pathway modulation.

• Disease Mechanism Studies:
  Recombinant Contactin-1 has been utilized in research on autoimmune nodopathies and cancer progression, serving as a tool to dissect its role in disease mechanisms, including its dysregulation in carcinomas and its function as an autoantigen in neuropathies.

Summary Table: Applications of Recombinant Human Contactin-1 in Research

Additional Notes:

• Most published studies use recombinant Contactin-1 expressed in mammalian or bacterial systems, often with affinity tags for purification and detection.
• The protein is frequently used in both in vitro biochemical assays and in vivo cellular models to dissect molecular mechanisms.
• While some commercial sources recommend applications such as immunogen and protein standard, published research most often validates recombinant Contactin-1 in mechanistic and functional assays relevant to neuroscience, immunology, and oncology.

If you require protocols or more specific details about a particular application, please specify the context or experimental system.

To reconstitute and prepare Recombinant Human Contactin-1 protein for cell culture experiments, follow these general guidelines based on manufacturer recommendations and best practices:

Reconstitution

1. Reconstitution Buffer

   • Most recombinant Contactin-1 proteins are lyophilized and should be reconstituted with sterile, endotoxin-free PBS (phosphate-buffered saline) or sterile distilled water, unless otherwise specified by the Certificate of Analysis (COA) or product datasheet.
   • For example, Leinco Technologies recommends reconstituting with sterile PBS or water, while Cayman Chemical and MedChemExpress do not specify a buffer but recommend sterile, distilled water for general use.

2. Concentration

   • Reconstitute to a concentration typically between 0.1–1.0 mg/mL. For example, if you have 100 µg of protein, add 100–1000 µL of buffer to achieve the desired concentration.
   • Always refer to the COA or datasheet for lot-specific instructions.

3. Procedure

   • Centrifuge the vial briefly before opening to ensure all lyophilized powder is at the bottom.
   • Add the appropriate volume of buffer slowly down the side of the vial to avoid foaming.
   • Gently swirl or rotate the vial until the protein is fully dissolved. Avoid vigorous shaking to prevent denaturation.

Preparation for Cell Culture

1. Sterility

   • Ensure all buffers and equipment are sterile to prevent contamination of cell cultures.

2. Storage

   • After reconstitution, aliquot the protein and store at 2–8°C for short-term use (up to one month) or at –20°C to –70°C for long-term storage.
   • Avoid repeated freeze-thaw cycles to maintain protein activity.

3. Dilution for Cell Culture

   • Dilute the reconstituted protein in serum-free cell culture medium or PBS to the desired working concentration.
   • If using serum-containing medium, ensure compatibility with the protein and your experimental system.

4. Quality Control

   • Check the protein concentration using a suitable assay (e.g., Bradford or BCA).
   • Verify activity and purity if possible, especially for sensitive cell culture experiments.

Additional Notes

• Always refer to the specific product datasheet or COA for lot-specific instructions, as formulations and recommendations may vary between suppliers.
• For cell culture applications, it is advisable to test the protein in a small-scale experiment to confirm activity and compatibility with your cell type.

By following these steps, you can ensure proper reconstitution and preparation of Recombinant Human Contactin-1 protein for use in cell culture experiments.