Recombinant Human Interferon-gamma (IFNy)
(Cat. No.: C014)

Background:
        The major interferon produced by mitogenically or antigenically stimulated lymphocytes. It is structurally different from type I interferon and its major activity is immunoregulation. It has been implicated in the expression of class II histocompatibility antigens in cells that do not normally produce them, leading to autoimmune disease. Interferon gamma is produced mainly by T-cells and natural killer cells activated by antigens, mitogens, or alloantigens. It is produced by lymphocytes expressing the surface antigens CD4 and CD8. The synthesis of IFN-gamma is induced, among other things, by Interleukin-2, FGF-basic, and EGF.

Description:
        Recombinant Human Interferon gamma produced in E. coli is a single, non-glycosylated, polypeptide chain containing 144 amino acids and having a molecular mass of 16879 Dalton.

Quality Control:
        Biological activity: The specific activity as determined in a viral resistance assay using VSV-WISH cells was found to be greater than 1.5 x 10⁷ 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: 16.8KD+/-10% determined by reduced SDS-PAGE.
        Isoelectric Point: the main zone between 8.1~9.1 analysis by IEF.
        Residual DNA: less than 300ng/mg analysis by solid phase blot.
        UV scan: the maximal absorption wave is 280+/-3nm.
        Amino-Acid Sequence: The sequence of the first fifteen N-terminal amino acids was determined and was found to be Gln-Asn-Pro-Tyr-Val-Lys-Glu-Ala-Glu-Asn-Leu-Lys-Lys- Tyr-Phe.
        Residual host cell protein: less than 0.1% analysis by ELISA.
        Endotoxin: Less than 1ng/µg (1IEU/µg) determined by LAL test.

Formulation: The protein was lyophilized after extensive dialysis from a concentrated (1mg/ml) solution in 10mM sodium Phosphate buffer pH=7.4+/-0.1.

Storage: Lyophilized rHuIFN-gamma although stable at room temperature for 3 weeks, should be stored desiccated below -18^oC. Upon reconstitution rHuIFN-gamma should be stored at 4^oC between 2-7 days and for future use below -18^oC. 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-gamma in sterile 18MΩ-cm H₂O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.