Description
IL-28B (also named interferon-lambda 3, IFN-lambda 3), IL-28A (IFN-lambda 2) and IL-29 (IFN-lambda 1) are type III interferons that are class II cytokine receptor ligands. They are distantly related to members of the IL-10 family and type I IFN family. Human IL-28B cDNA encodes a 200 amino acid (aa) protein with a 25 aa signal peptide and a 175 aa mature protein that lacks N-glycosylation sites. Mature human IL-28B shares 64% and 75% aa sequence identity with mouse and canine IL-28B, respectively, and is active across species. Human IL-28B shares 94% and 69% aa identity with human IL-28A and IL29, respectively. Type III interferons are widely expressed, but are mainly produced by antigen presenting cells in response to viruses and double-stranded RNA that interact with Toll-like receptors or RIG-1 family helicases. They signal through a widely expressed receptor that is a heterodimer of the IL-10 receptor beta (IL-10 R beta ) and IL-28 receptor alpha (IL-28 R alpha ; also called IFN-lambda R1). Interaction of either type I or type III IFNs with their receptors activates similar pathways, including JAK tyrosine kinase activation, STAT phosphorylation and formation of the IFN-stimulated regulatory factor 3 (ISGF-3) transcription factor complex. Both type I and III IFNs induce antiviral activity and upregulate MHC class I antigen expression. Cell lines responsive to type III IFNs are also responsive to type I IFNs, but in general, higher concentrations of type III IFNs are needed for similar in vitro responses. In vivo, however, type III IFNs enhance levels of IFN-gamma in serum, suggesting that the robust anti-viral activity of type III IFNs may stem in part from activation of the immune system. Anti-proliferative and antitumor activity in vivo has also been shown for type III IFNs.
Product Properties
Synonyms |
Interleukin 28B;Interferon lambda-3;IFN-lambda-3;Interleukin-28B |
Accession |
|
GeneID |
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Source |
E.coli-derived mouse Interferon-lambda3/Interleukin-28B protein, Asp20-Val193 |
Molecular Weight |
Approximately 19.6 kDa. |
AA Sequence |
DPVPRATRLP VEAKDCHIAQ FKSLSPKELQ AFKKAKGAIE KRLLEKDMRC SSHLISRAWD LKQLQVQERP KALQAEVALT LKVWENINDS ALTTILGQPL HTLSHIHSQL QTCTQLQATA EPKPPSRRLS RWLHRLQEAQ SKETPGCLED SVTSNLFQLL LRDLKCVASG DQCV |
Tag |
None |
Physical Appearance |
Sterile Filtered White lyophilized (freeze-dried) powder. |
Purity |
> 98 % by SDS-PAGE and HPLC analyses. |
Biological Activity |
Fully biologically active when compared to standard. The ED50 as determined by an anti-viral assay using human HepG2 cells infected with encephalomyocarditis is less than 30 ng/ml, corresponding to a specific activity of > 3.3 × 104 IU/mg. |
Endotoxin |
< 1.0 EU per 1μg of the protein by the LAL method. |
Formulation |
Lyophilized from a 0.2 µm filtered concentrated solution in PBS, pH 7.4. |
Reconstitution |
We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1 % BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20 °C. Further dilutions should be made in appropriate buffered solutions. |
Shipping and Storage
The products are shipped with ice pack and can be stored at -20℃ to -80℃ for 1 year.
Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles.
Cautions
1. Avoid repeated freeze-thaw cycles.
2. For your safety and health, please wear lab coats and disposable gloves for operation.
3. For research use only!