Background:
Assay Used to Measure Bioactivity: Interferon was titrated with the use of the cytopathic effect inhibition assay as described [Rubinstein, S., Familletti, P.C., and Pestka, S. (1981) "Convenient Assay for Interferons," J. Virol. 37, 755-758; Familletti, P.C., Rubinstein, S., and Pestka, S. (1981) "A Convenient and Rapid Cytopathic Effect Inhibition Assay for Interferon," in Methods in Enzymology, Vol. 78 (S. Pestka, ed.), Academic Press, New York, 387-394]. In this antiviral assay for interferon about 1 unit/ml of interferon is the quantity necessary to produce a cytopathic effect of 50%. The units are determined with respect to the international reference standard for mouse interferon gamma (mouse IFN-g) provided by the National Institutes of Health [see Pestka, S. (1986) "Interferon Standards and General Abbreviations," in Methods in Enzymology (S. Pestka, ed.), Academic Press, New York 119, 14-23]. Unit of activity measured on mouse L929 cells with encephalomyocarditis virus (EMCV).
Specific Activity:
~1x10e7units/mg
Storage and Stability:
Product should be kept at -70 degrees C or below for retention of full activity. When thawing, the contents should be aliquoted to keep freezing and thawing to a minimum.