App Note I July 13, 2015

Characterization of a high-affinity anti-EPO antibody by switching speed measurements

Erythropoietin (EPO) is a glycoprotein that upregulates the production of red blood cells. Recombinantly produced EPO is used as a drug to treat anemia and also as an illegal doping agent in sports. Understanding the interaction of antibodies with EPO is important for the diagnosis of a potentially fatal immune response of patients to exogenous EPO as well as for the development of assays for the in-vitro detection of EPO. The kinetic rate constants as well as the dissociation constant were successfully determined for a high-affinity monoclonal antibody against EPO. A quick quantification of the Ab concentration is possible by analyzing the initial signal change after Ab injection. Sub-pM concentrations of the antibody could be detected in less than 20 min.