Immunoradiometric assay of a recombinant human alpha-2 interferon ( XXXX ).

@entity852 @entity1522 @entity13518 @entity10125 @entity4020 @entity69648
A sensitive immunoradiometric assay for recombinant alpha-2 interferon ( @entity4020 ; @entity69648 ) was developed by using the monoclonal antibody @entity10125 . A @entity852 bead with polyclonal sheep anti-human @entity4020 (Hu @entity4020 ) antibody adsorbed to it formed the solid phase of the assay. The monoclonal antibody, labeled with 125I, reacted with the @entity4020 which bound to the polyclonal antibody on the bead. The assay was sensitive, capable of measuring less than 5 IU/ml, and it was precise. Coefficients of variation were less than 10%, often less than 5%. Interassay coefficients of variation for the same sample were also less than 10%. Specificity of the monoclonal antibody for @entity4020 was greater than for Hu @entity4020 produced by leukocytes. In specificity studies it was necessary to add at least 200 IU of Hu @entity4020 per ml to 25 IU of @entity4020 per ml before the Hu @entity4020 affected the accuracy of the assay of @entity4020 . Accuracy as determined by correlation studies with the antiviral cytopathic effect assay was very high. Results of the two assays usually agreed within 15%. This correlation was maintained in studies of @entity4020 after storage under accelerated degradation conditions, when the IFN was cleaved into smaller sequences of @entity1522 by @entity13518 and when the IFN was carboxymethylated.
