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 5ng/ml, corresponding to a specific activity of >2.0×105IU/mg.
Physical Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.
Formulation
Lyophilized from a 0.2μM filtered concentrated solution in PBS, pH7.4.
Endotoxin
Less than 1EU/μg of rHuIFN-λ1/IL-29 as determined by LAL method.
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 0.1-1.0mg/ml. Stock solutions should be apportioned into working aliquots and stored at ≤-20℃. Further dilutions should be made in appropriate buffered solutions.
Category
Cytokine
Background
IL-28A, IL-28B, and IL-29, also named interferon-λ2 (IFN-λ2), IFN-λ3, and IFN-λ1, respectively, are newly identified class II cytokine receptor ligands that are distantly related to members of the IL-10 family (11-13%a.a. sequence identity) and the type I IFN family (15-19%a.a. sequence identity). The expression of IL-28A, B, and IL-29 is induced by virus infection or doublestranded RNA. All three cytokines exert bioactivities that overlap those of type I IFNs, including antiviral activity and upregulation of MHC class I antigen expression. The three proteins signal through the same heterodimeric receptor complex that is composed of the IL-10 receptor β (IL-10 Rβ) and a novel IL-28 receptor α (IL-28 Rα, also known as IFN-λR1). Ligand binding to the receptor complex induces Jak kinase activation and STAT1 and STAT2 tyrosine phosphorylation.