Recombinant Human Oncostatin M

Recombinant Human Oncostatin M (OSM) is widely used in research because it is a multifunctional cytokine with key roles in inflammation, cell differentiation, proliferation, hematopoiesis, tissue remodeling, and cancer biology. Using the recombinant form ensures high purity, batch-to-batch consistency, and species specificity, which are critical for reproducible and interpretable experimental results.

Key scientific applications and rationales for using Recombinant Human OSM:

• Modeling Inflammatory Diseases: OSM is a member of the interleukin-6 (IL-6) cytokine family and is implicated in the pathogenesis of inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, and severe COVID-19, where it contributes to cytokine storm and tissue damage. Recombinant OSM allows for controlled studies of these mechanisms in vitro and in vivo.

• Cancer Research: OSM regulates tumor cell proliferation, invasion, and metastasis. It promotes the expression of proteases and proangiogenic factors (e.g., VEGF, HIF1α), and its signaling is associated with tumor recurrence and poor prognosis in several cancers. Recombinant OSM is used to dissect these pathways and to screen for inhibitors targeting OSM/OSMR signaling.

• Cell Differentiation and Development: OSM is essential for the differentiation of liver progenitor cells, osteogenesis, neurogenesis, and hematopoiesis. It is commonly used in protocols for generating hepatocyte-like cells from stem cells and for studying bone and nerve development.

• Functional Assays: Recombinant OSM is used in bioassays to induce cytokine production (e.g., G-CSF, GM-CSF), activate STAT3 signaling, and modulate gene expression in various cell types, including endothelial cells, fibroblasts, and immune cells.

• Drug Discovery and Structural Biology: Recombinant, isotopically labeled OSM is valuable for NMR-based drug screening and structure-function studies, enabling the identification of small molecule inhibitors and mapping of binding sites.

• Reproducibility and Standardization: Recombinant proteins provide defined activity and concentration, reducing variability compared to native or serum-derived cytokines. This is crucial for quantitative and comparative studies.

Summary of major research uses:

• Studying inflammatory signaling and cytokine networks
• Modeling and manipulating tumor microenvironments
• Inducing differentiation in stem cell and organoid systems
• Screening and characterizing OSM pathway inhibitors
• Investigating tissue remodeling, wound healing, and fibrosis

In summary, Recombinant Human Oncostatin M is a versatile tool for dissecting cytokine biology, disease mechanisms, and therapeutic interventions in a controlled and reproducible manner.

Yes, recombinant human Oncostatin M can be used as a standard for quantification or calibration in ELISA assays, provided it is appropriately formulated and validated for this purpose.

Essential context and supporting details:

• Formulation: Recombinant Oncostatin M is often supplied with carrier proteins such as BSA to enhance stability and solubility, which is suitable for use as an ELISA standard. Carrier-free formulations are also available, but these are typically recommended for bioassays rather than ELISA calibration unless specifically validated for standard curve generation.

• Validation: It is critical that the recombinant protein used as a standard is validated for ELISA applications. Many ELISA kits and DuoSet development kits specify that their standards can be either natural or recombinant human Oncostatin M, and they are calibrated to ensure accurate quantification in biological samples. The standard should be reconstituted and diluted according to the manufacturer’s instructions to generate a reliable standard curve.

• Matrix Effects: When using recombinant Oncostatin M as a standard, ensure that the diluent used for the standard curve matches the sample matrix as closely as possible to minimize matrix effects and ensure accurate quantification. Internal controls and parallelism studies are recommended to confirm that the recombinant standard behaves similarly to endogenous Oncostatin M in your sample type.

• Assay Compatibility: Most commercial ELISA kits for Oncostatin M are designed to detect both natural and recombinant forms, and their standard curves are typically generated using recombinant protein. Always confirm that your assay’s antibodies recognize the recombinant form you intend to use.

• Best Practices:

  • Reconstitute the recombinant protein in the recommended buffer (often PBS with 0.1% BSA) to maintain stability and reproducibility.
  • Prepare fresh standard dilutions for each assay, as working standards may not store well.
  • Validate the linearity and recovery of the recombinant standard in your specific sample matrix.

Summary of scientific application:

• Recombinant human Oncostatin M is widely used as a standard for ELISA quantification, provided it is formulated and validated for this purpose.
• Always follow best practices for reconstitution, dilution, and validation to ensure accurate calibration and quantification in your ELISA assays.

Recombinant human Oncostatin M (OSM) has been validated for a diverse range of applications across multiple research domains, as demonstrated in published literature.

Molecular and Cellular Assays

The protein has been extensively validated for functional assays, ELISA, and Western blot applications. These techniques are fundamental for detecting OSM-induced signaling events, particularly the phosphorylation of STAT3, which serves as a key biomarker of OSM receptor activation. Mass spectrometry and circular dichroism have also been employed to characterize the protein's purity and structural integrity.

Cell Culture and Differentiation Studies

Recombinant OSM has been validated for use in cell culture and differentiation applications. Research has demonstrated its utility in studying stem cell fate determination, including the differentiation of human embryonic stem cells toward hepatocyte-like cells and definitive endoderm lineages. The protein has also been applied in pluripotent stem cell-based platforms for investigating viral tropism and infection models.

Immunological and Inflammatory Research

OSM has been validated in bioassay applications examining immune cell responses. Published studies have utilized recombinant OSM to investigate its effects on dendritic cell trafficking, endothelial cell activation in both macro- and microvascular contexts, and its role in modulating cytokine production during inflammatory responses. The protein has been used to study OSM's interactions with synovial fibroblasts in inflammatory contexts.

Wound Healing and Tissue Regeneration

Recombinant murine OSM has been validated for topical wound healing applications, with studies demonstrating improved wound re-epithelialization and accelerated healing in full-thickness excisional wounds.

Structural and Drug Discovery Applications

For advanced applications, isotopically enriched recombinant OSM has been validated for NMR-based structural studies and small molecule screening. This application has enabled direct binding studies with small molecule inhibitors and structure-based drug design approaches.

Immunohistochemistry

The protein has been validated for immunohistochemistry applications, enabling visualization of OSM signaling in tissue contexts.

To reconstitute and prepare Recombinant Human Oncostatin M (OSM) protein for cell culture experiments, follow these best-practice steps:

• Reconstitution Concentration: Reconstitute the lyophilized OSM at 100 μg/mL in sterile PBS (phosphate-buffered saline). For enhanced stability and to prevent protein adsorption to surfaces, include at least 0.1% human or bovine serum albumin (BSA) as a carrier protein. Some protocols recommend up to 1% BSA or 5–10% fetal bovine serum (FBS) for even greater stability.

• Procedure:

  • Briefly centrifuge the vial to collect the lyophilized powder at the bottom before opening.
  • Add the appropriate volume of sterile PBS (with carrier protein) directly to the vial to achieve the desired concentration (e.g., 100 μg/mL).
  • Gently mix by pipetting up and down or by gentle swirling. Do not vortex, as vigorous agitation can denature the protein.
  • Allow the protein to fully dissolve at room temperature for 20–30 minutes, with occasional gentle mixing.

• Aliquoting and Storage:

  • Once fully dissolved, aliquot the solution into small volumes to avoid repeated freeze-thaw cycles, which can degrade the protein.
  • Store aliquots at –20°C or –80°C for long-term storage. For short-term use (up to 1 week), store at 4°C.
  • Avoid repeated freeze-thaw cycles.

• Working Solution Preparation:

  • Before adding to cell cultures, dilute the stock solution to the desired working concentration using cell culture medium or PBS with carrier protein. Typical working concentrations for bioassays range from 0.05–0.3 ng/mL (ED₅₀ for TF-1 cell proliferation), but optimal concentrations should be empirically determined for your specific application.

Key technical notes:

• Always check the product-specific datasheet or Certificate of Analysis for any unique instructions, as formulations may vary between suppliers.
• If using a carrier-free preparation, ensure all solutions and plasticware are low-protein binding to minimize loss of protein due to adsorption.
• For animal-free or serum-free applications, use recombinant human albumin or other defined carriers as appropriate.

Summary Table:

This protocol ensures maximal stability and biological activity of recombinant human Oncostatin M for cell culture experiments.