Interleukin-28A (IL-28A), also known as IFN-λ2, is a cytokine distantly related to type I interferons and the IL-10 family. It exerts its biological effects through a receptor that also binds IL-28B and IL-29 (1). This receptor is a heterodimeric class II cytokine receptor that consists of IL-10RB and IL-28RA. IL-28A activities overlap those of type I IFNs and include anti-viral activity and up-regulation of MHC class I antigen expression (2). The expression of IL-28A is induced by virus infection or double-stranded RNA. Upon binding to the receptor, it also induces JAK kinase activation and phosphorylation of STAT and STAT2 (3). IL-28A represents a potential novel approach for therapy of Th1-mediated inflammatory diseases such as T cell-mediated hepatitis (4).
>97% by SDS-PAGE and analyzed by silver stain.
<0.1 EU/µg as determined by the LAL method
The biological activity of Human IFN-λ2 was determined by in an anti-viral assay using human HepG2 cells infected with encephalomyocarditis virus (Sheppard, P. et al., 2003, Nature Immunol. 4:63). The expected ED50 for this effect is typically 1 - 5 ng/ml.
Fusion Protein Tag
Protein Accession No.
Amino Acid Sequence
vpvar lhgalpdarg chiaqfksls pqelqafkra kdaleeslll kdcrchsrlf prtwdlrqlq vrerpmalea elaltlkvle atadtdpalv dvldqplhtl hhilsqfrac iqpqptagpr trgrlhhwly rlqeapkkes pgcleasvtf nlfrlltrdl ncvasgdlcv dihhhhhh
N-terminal Sequence Analysis
State of Matter
Predicted Molecular Mass
The predicted molecular weight of Recombinant Human IL-28A is Mr 20.8 kDa. However, the actual molecular weight as observed by migration on SDS-PAGE is Mr 24 kDa.
This recombinant protein was 0.2 µm filtered and lyophilized from modified Dulbecco’s phosphate buffered saline (1X PBS) pH 7.2 – 7.3 with no calcium, magnesium, or preservatives.
Storage and Stability
This lyophilized protein is stable for six to twelve months when stored desiccated at -20°C to -70°C. After aseptic reconstitution, this protein may be stored at 2°C to 8°C for one month or at -20°C to -70°C in a manual defrost freezer. Avoid Repeated Freeze Thaw Cycles. See Product Insert for exact lot specific storage instructions.
Country of Origin
Next Day Ambient
NCBI Gene Bank
References & Citations
1. Zitzmann, K. et al. (2006) Biochem. Biophys. Research Commun. 344:1334
2. Kotenko, SV. et al. (2003) Nat. Immunol. 4:69
3. Maher, SG. et al. (2008) Cancer Biol. Ther. 7:1109
4. Neurath, MF. et al. (2007) Gastroenterology 132:358
IMPORTANT Use lot specific datasheet for all technical information pertaining to this recombinant protein.
Products are for research use only. Not for use in diagnostic or therapeutic procedures.