INTRODUCTION

Rituximab (Rituxan® ) is a chimeric mouse/human monoclonal antibody used for treating B cell malignancy, autoimmune conditions, and graft rejection by depleting B cells from the body. This immunogenicity assay employs the bridging ELISA technique. Four levels of QC samples give a qualitative reference signal which can be used to determine the level of anti- Rituximab antibody in the unknown samples. The color development is stopped and the intensity of the color is measured.

PRINCIPLE OF THE ASSAY

This immunogenicity assay employs the bridging ELISA technique. Capture antibody is precoated onto a 96 well microplate. Quality control and test samples are pipetted into the appropriate wells. Anti- Rituximab present in biological matrices is bound by the immobilized capture antibody. After washing away any unbound substances, secondary antibody is added to the wells and after a final wash a detection reagent is added. The plate is washed to remove any unbound antibody-enzyme reagent and a substrate solution is added to the wells for color development.
The color development is proportional to the amount of anti-Rituximab present in test samples. Three levels of QC samples give a qualitative reference signal which can be used to determine the level of anti-Rituxumab antibody in the unknown samples. The color development is stopped and the intensity of the color is measured.