Description : |
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 double-stranded RNA. All three cytokines exert bioactivities that overlap those of type I IFNs, including antiviral activity and up-regulation 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. |
Source : |
E.coli |
Species : |
Human |
Form : |
Lyophilized from a 0.2μm filtered concentrated solution in PBS, pH 7.4. |
Bio-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 5 ng/ml, corresponding to a specific activity of > 2.0 × 10⁵ IU/mg. |
Molecular Mass : |
Approximately 19.8 kDa, a single non-glycosylated polypeptide chain containing 181 amino acids. |
Protein length : |
181 |
AA Sequence : |
GPVPTSKPTTTGKGCHIGRFKSLSP QELASFKKARDALEESLKLKNWSCS SPVFPGNWDLRLLQVRERPVALEAE LALTLKVLEAAAGPALEDVLDQPLH TLHHILSQLQACIQPQPTAGPRPRG RLHHWLHRLQEAPKKESAGCLEASV TFNLFRLLTRDLKYVADGNLCLRTS THPEST |
Endotoxin : |
Less than 1 EU/μg of rHuIFN-λ1/IL-29 as determined by LAL method. |
Purity : |
>97% by SDS-PAGE and HPLC analysis. |
Storage : |
Use a manual defrost freezer and avoid repeated freeze-thaw cycles. 12 months from date of receipt, -20 to -70 centigrade as supplied. 1 month, 2 to 8 centigrade under sterile conditions after reconstitution. 3 months, -20 to -70 centigrade under sterile conditions after reconstitution. |
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 centigrade. Further dilutions should be made in appropriate buffered solutions. |