Recombinant @entity19 -human chimeric antibodies as calibrators in immunoassays that measure antibodies to XXXX .

@entity1 @entity19 @entity19490 @entity3204 @entity9510
In the present study, we examined the feasibility of using recombinant antibodies containing @entity19 variable regions and @entity1 constant regions as calibrators or controls in immunoassays. As a model system, we chose the Abbott IMx Toxo immunoglobulin M (IgM) and Toxo IgG assays designed to detect antibodies to @entity3204 . Two mouse monoclonal antibodies were selected based on their reactivity to the T. gondii antigens @entity9510 and @entity19490 . Heavy- and light-chain variable-region genes were cloned from both hybridomas and transferred into immunoglobulin expression vectors containing @entity1 kappa and IgG1 or IgM constant regions. The constructs were stably transfected into Sp2/0-Ag14 cells. In the IMx Toxo IgG assay, immunoreactivity of the anti- @entity9510 chimeric IgG1 antibody paralleled that of the positive @entity1 plasma-derived assay calibrators. Signal generated with the anti- @entity19490 chimeric IgG1 antibody was observed to plateau below the maximal reactivity observed for the assay calibrator. Examination of the IgM chimeric antibodies in the IMx Toxo IgM assay revealed that both the anti- @entity9510 and anti- @entity19490 antibodies matched the assay index calibrator manufactured with @entity1 Toxo IgM-positive plasma. When evaluated with @entity1 samples, the correlation between results obtained with the chimeric antibody calibrators and the positive @entity1 plasma calibrators was > or =0.985. These data demonstrate that chimeric mouse-human antibodies are a viable alternative to high-titer positive @entity1 plasma for the manufacture of calibrators and controls for diagnostic assays.
