Human embryonic kidney cell, HEK293-derived human IFN-alpha 4 protein Cys24-Asp189
>95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
<0.10 EU per 1 μg of the protein by the LAL method.
N-terminal sequence Analysis
Predicted Molecular Mass
17-23 kDa, under reducing conditions.
Measured in anti-viral assays using HeLa human cervical epithelial carcinoma cells infected with encephalomyocarditis (EMC) virus. Meager, A. (1987) in Lymphokines and Interferons, a Practical Approach. Clemens, M.J. et al. (eds): IRL Press. 129. The ED50 for this effect is 1.00-20.0 pg/mL.
Recombinant Human IFN-alpha-4A Protein, CF Scientific Data Examples
Recombinant Human IFN-alpha-4A Protein Bioactivity.
Recombinant Human IFN-alpha-4A Protein (Catalog # 10998-IF) demonstrates anti-viral activity in HeLa human cervical epithelial carcinoma cells infected with encephalomyocarditis (EMC) virus. The ED50 for this effect is 1.00‑20.0 pg/mL
Recombinant Human IFN-alpha-4A Protein SDS-PAGE.
2 μg/lane of Recombinant Human IFN-alpha-4A Protein (Catalog # 10998-IF) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 17-23 kDa, under reducing conditions.
Formulation, Preparation and Storage
What does CF mean?
CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our
Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant
protein to be stored at a more dilute concentration.
The carrier free version does not contain BSA.
What formulation is right for me?
In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or
as an ELISA standard.
In contrast, the carrier free protein is recommended for applications, in which the presence of BSA
Lyophilized from a 0.2 μm filtered solution in PBS.
Reconstitute at 100 μg/mL in PBS.
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage:
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
3 months, -20 to -70 °C under sterile conditions after reconstitution.
Background: IFN-alpha 4
Interferons (IFN) are a family of cytokines with potent antiviral, antiproliferative and immunomodulatory properties, classified based on their binding specificity to cell surface receptors (1). Human IFNA2 was originally cloned in the early ‘80s and now more than a dozen closely related IFN alpha subtypes have been identified in both the human and mouse genome, each sharing about 80% amino acid (aa) sequence homology (2-4). Structurally, type I IFNs belong to the class of five helical‑bundle cytokines, with the IFNA subtypes containing 2 conserved disulfide bonds (5). The mature human IFNA4 shares 57% aa sequence identity with mouse IFNA4. Two variants of human IFNA4 are known to exist, IFNA4a and IFNA4b, which only differ by residues at aa position 74 and 137 (6). The type I IFNs bind to the interferon alpha receptor (IFNAR), which consists of two subunits: IFNAR1 (alpha -subunit) and IFNAR2 (beta -subunit) (7, 8). Individual IFNA subtypes are known to display unique efficacies to viral protection, and IFNA4 has been shown to be an intermediate inducer of IFN-stimulated genes and anti-viral protection (9). Mutations in IFNA4 can cause impaired function and lead to Crohn's disease susceptibility (10). IFNA4 also exhibits strong antiviral effects against SARS-CoV-2 (11).
Pestka, S. et al. (1987) Annu Rev Biochem. 56:727.
Goeddel, D.V. et al. (1980) Nature 287:411.
Matsumiya, T. et al. (2007) J. Immunol. 179:4542.
Schreiber, G. and J. Piehler (2015) Trends Immunol. 36:139.
Wittling, M.C. et al. (2021) Front Immunol. 11:605673.
Hussain, M. et al. (1997) J. Interferon Cytokine Res. 17:559.
Which Brands are Currently Available on bio‑techne.com? R&D Systems, Tocris Bioscience and ProteinSimple branded products are available to purchase through bio‑techne.com. ProteinSimple branded instruments are available to quote. ACD branded products will be available on bio‑techne.com in the near future. Novus Biologicals branded products are not currently available on bio‑techne.com and can be found at novusbio.com.
Setting the standard in quality research reagents for over 30 years
A trusted leader in quality life science reagents
Your trusted supplier for innovative and high performance life science reagents
Proprietary systems and consumables for simpler, more quantitative and affordable protein analysis
Proprietary RNAscope® technology capable of detecting and quantifying RNA biomarkers in situ at single molecule sensitivity
A world leader in developing liquid biopsy based diagnostics