Isotype Control Antibodies

Isotype control antibodies serve as essential negative controls for identifying non-specific binding in immunoassays such as flow cytometry and immunohistochemistry. While isotype control antibodies are raised in the same host species and share the same class of immunoglobulin (e.g. IgG, IgM, etc.) as the experimental antibody, their antigen binding Fab region is specific for an antigen that is not expressed in the sample being studied. This means that any signal observed in an isotype control condition is likely due to a non-specific interaction with the constant Fc region of the antibody, such as by interacting with Fc receptors on cells of the immune system. Including isotype control antibodies in an experiment allows researchers to identify specific signal and therefore correctly interpret experimental results. See our guides on isotype controls or controls to run for immunohistochemistry, flow cytometry, and ChIP for more information on choosing the perfect isotype control for your experiment.