VALIDATION PARAMETERS FOR A NOVEL BIOSENSOR ASSAY WHICH SIMULTANEOUSLY MEASURES SERUM CONCENTRATIONS OF A HUMANIZED MONOCLONAL-ANTIBODY ANDDETECTS INDUCED ANTIBODIES

This report documents the validation of an assay using BIAcore 2000 th at, with a single injection of mouse serum, allows the quantitation of a humanized monoclonal antibody and can also detect the presence of a ntibodies directed against this humanized antibody. The important comp onents required for the validation of biosensor assays including preci sion, accuracy, linearity, stability of the immobilized Ligand, specif icity and sensitivity are addressed. The tandem assay that is used as a model for biosensor validations is accomplished by flowing each samp le across the surface of two flowcells in sequence. The first flowcell has the antigen that the humanized mAb was generated against immobili zed while the humanized mAb itself is immobilized on the second flowce ll. The quantitation component of this assay is precise and accurate w ith a limit of quantitation of 1 mu g/ml in mouse serum samples. Any a ntibodies directed against the humanized mAb can be detected and also characterized as to isotype. This unique assay can be performed with a s little as 10 mu l of serum which is then diluted ten-fold prior to a nalysis. The small sample requirement allows analysis of individual mo use serum samples rather than requiring the use of pooled samples from multiple mice. A further advantage of this assay is the automation ca pability which allows unattended operation. (C) 1997 Elsevier Science B.V.