SYSTEM FOR THE ADAPTATION OF CELL-BASED ASSAYS FOR ANALYSIS ON AUTOMATED IMMUNO-ASSAY PLATFORMS

摘要

Cell based assays are required for the detection of biological activity and hence are required for use as potency assays, detection of neutralizing antibodies and detection and quantification of the effector cell function of therapeutic antibodies or the quantification of the potency or neutralizing antibody response to virus vectors such as AAV vectors used in gene therapy. Cell-based assay are also required for the quantification of antibody mediated effector functions including complement-dependent cytotoxicity (CDC), antibody-dependent cellular phagocytosis (ADCP), and antibody- dependent cell-mediated cytotoxicity (ADCC). Cell based assays are difficult to adapt for use on automated immuno-assay platforms. Reporter-genes that encode readily visible proteins that can be quantified using fluorescence or luminescence such as luciferases (firefly, Renilla, Gaussia, Nano Luciferase etc), fluorescent proteins such as green fluorescent protein (GFP) or dsRED or an enzyme such as chloramphenicol acetyltransferase (CAT) or a protease and respond to signal transduction, that is directly related to the mechanism of action of a drug, can be used to quantify the potency of a drug following binding of a drug to a soluble target or cell surface target (receptor or other cell-surface molecule), anti-drug neutralizing antibodies, and therapeutic antibody induced effector cell function. The principal of the invention is that reporter-gene product or by-product produced either during the course of the cell-based assay or onconclusion of the cell based assay is quantified either in the cell medium or cell supernatant, for a secreted protein, or following lysis of the cells with a suitable passive lysis buffer. The reporter- gene product such as firefly luciferase is then detected in the cell medium or cell supernatant or cell lysate using an antibody pair (monoclonal or polyclonal) specific for the gene product such as a firefly luciferase labelled with the dual detection system specific for an ELISA or a particular automated assay platform such as Meso Scale Discovery electro- chemiluminescence (MSD-ECL), Luminex, SMC, Alpco, AlphaLISA, Gyros or label free detection using SPR such as the Biacore platform. The expression of the reporter-gene product such as firefly luciferase can be normalized with respect to the expression of a second reporter gene product such as Renilla luciferase or Nano Luciferase under the control of a constitutive promoter.