Recombinant Human Interferon-alpha 2b (IFNa2b)
(Cat. No.: C005)
At least 23 different variants of IFN-alpha are known. The individual proteins have molecular masses between 19-26 kDa and consist of proteins with lengths of 156-166 and 172 amino acids. All IFN-alpha subtypes possess a common conserved sequence region between amino acid positions 115-151 while the amino-terminal ends are variable. Many IFN-alpha subtypes differ in their sequences at only one or two positions. Naturally occurring variants also include proteins truncated by 10 amino acids at the carboxyl-terminal end.
Recombinant Human Interferon-alpha 2b produced in E. coli is a single, non-glycosylated, polypeptide chain containing 166 amino acids and having a molecular mass of 19400 Dalton. The Interferon-alpha 2b gene was obtained from human leukocytes.
Biological activity: The specific activity as determined in a viral resistance assay using VSV- WISH cells was found to be greater than 1.0 x 108 IU/ mg.
Purity: Greater than 95% as determined by
(a) Analysis by SEC-HPLC.
(b) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
Molecular weight: 19.2KD+/-10% determined by reduced SDS-PAGE.
Isoelectric Point: The main zone between 5.5~6.8 analysis by IEF.
UV Scan: The maximal absorption wave is 278+/-3nm.
Amino-Acid Sequence: The sequence of the first fifteen N-terminal amino acids was determined and was found to be Met-Cys-Asp-Leu-Pro-Gln-Thr-His-Ser-Leu-Gly-Ser-Arg- Arg-Thr-Leu.
Residual DNA: less than 300ng/mg analysis by solid phase blot.
Residual host cell protein: less than 0.1% analysis by ELISA.
Endotoxin: Less than 0.3ng/µg (0.3IEU/µg) determined by LAL test.
Formulation: Lyophilized from a (1mg/ml) solution in containing 8.8mg sodium chloride, 0.4mg sodium acetate and 1.0mg acetate acid buffer.
Storage: Lyophilized rHuIFN-alpha 2b although stable at room temperature for 3 weeks, should be stored desiccated below -18oC. Upon reconstitution rHuIFN-alpha 2b should be stored at 4oC between 2-7 days and for future use below -18oC. For long-term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please avoid freeze-thaw cycles.
Reconstitution: It is recommended to reconstitute the lyophilized rHuIFN-alpha2b in sterile 18MΩ-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.