IFNG Human, His Active
Description
Definition and Composition
"IFNG Human, His Active" is a recombinant protein produced by expressing the human IFNG gene in heterologous systems such as E. coli or HEK 293 cells. The protein includes a C-terminal or N-terminal His-tag for affinity chromatography purification . The mature protein spans amino acids 24–166 (or 24–161 in some constructs) and forms a homodimer essential for its biological activity .
Key Functions
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Immune Activation: Enhances antigen presentation via upregulation of MHC class I/II molecules and immunoproteasome subunits .
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Antiviral and Antitumor Effects: Activates macrophages, induces nitric oxide synthase (iNOS), and primes NK cells .
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Signaling Pathway: Binds to IFNGR1/IFNGR2 receptors, triggering JAK-STAT signaling and transcription of interferon-stimulated genes (ISGs) .
Mechanistic Insights
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The His-tag does not interfere with receptor binding or activity .
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Proteolytic processing at the C-terminus (e.g., Gly-150, Met-157) may influence heparan sulfate binding and receptor interaction kinetics .
Experimental Uses
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Cytotoxicity Assays: Validated in HT-29 cells to measure potency (ED<sub>50</sub> <1 ng/mL) .
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Immunoproteasome Studies: Induces PA28 and immunoproteasome subunits to enhance MHC-I peptide loading .
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Therapeutic Development: Used in screening monoclonal antibodies (e.g., Fontolizumab) that block IFN-γ signaling .
Comparative Activity
| Application | Details |
|---|---|
| Antiviral Activity | Synergizes with type I interferons to amplify antiviral responses . |
| Macrophage Activation | Upregulates IL-12 and cathepsins B/H/L for MHC-II antigen processing . |
Quality Control
Product Specs
Immune Interferon, type II interferon, T cell interferon, MAF, IFNG, IFG, IFI, IFN-gamma.
MGSSHHHHHH SSGLVPRGSH MQDPYVKEAE NLKKYFNAGH SDVADNGTLF LGILKNWKEE SDRKIMQSQI VSFYFKLFKN FKDDQSIQKS VETIKEDMNV KFFNSNKKKR DDFEKLTNYS VTDLNVQRKA IHELIQVMAE LSPAAKTGKR KRSQMLFRG.
Product Science Overview
Interferon-gamma (IFN-γ) is a dimerized soluble cytokine and the only member of the type II class of interferons. It plays a crucial role in the immune system by inhibiting viral replication directly and through its immunostimulatory and immunomodulatory effects . Human recombinant IFN-γ, particularly with a His tag, is a form of this cytokine that has been engineered for research and therapeutic purposes.
Recombinant human IFN-γ is typically produced in various expression systems, such as HEK293 cells or E. coli. The His tag, a sequence of histidine residues, is added to facilitate purification through affinity chromatography. This recombinant protein is often expressed as a single, non-glycosylated polypeptide chain containing 159 amino acids and having a molecular mass of approximately 18.4 kDa .
IFN-γ is known for its broad-spectrum antiviral properties. It is produced by lymphatic T cells and natural killer cells upon stimulation by antigens . The cytokine activates effector immune cells and enhances antigen presentation, making it a vital component in the body’s defense against infections and tumors . Recombinant IFN-γ retains these biological activities, making it a valuable tool in clinical research and therapeutic applications.
The production of recombinant human IFN-γ involves several steps:
- Gene Cloning: The gene encoding human IFN-γ is cloned into an expression vector.
- Transformation: The vector is introduced into a suitable host cell line, such as HEK293 or E. coli.
- Expression: The host cells are cultured under conditions that promote the expression of the recombinant protein.
- Purification: The His tag allows for easy purification of the protein using affinity chromatography techniques.
- Validation: The purity and biological activity of the recombinant protein are validated through various assays, such as SDS-PAGE and functional assays .
Recombinant human IFN-γ is used in various research and clinical applications, including:
- Antiviral Research: Studying the mechanisms of viral inhibition and developing antiviral therapies.
- Cancer Research: Investigating the role of IFN-γ in tumor suppression and developing immunotherapies.
- Immunology: Understanding the modulation of immune responses and the enhancement of antigen presentation .
