Chromium-51 Cellular Cytotoxicity Assay
ADCC assays are live cell-based assays consisting of an effector cell, an antibody, and a target cell. The assay consists of preincubating target cells are with a tracer, adding the antibody, if the matching antigen is present the target cell will have antibodies bound to it, then effector cells are added which recognize the antibodies and then lyse the target cell. The classic method which is the most sensitive and a direct measure of lysis is the Chromium-51 Release Assay in which radioactive sodium chromate is pre-incubated with the target cells, and upon lysis free Cr51 is determined by gamma counting or scintillation counting. The non-radioactive calcein-AM Assay has been used as an alternative which is an indirect measure of cell lysis determined by fluorescence absorption spectroscopy.