Production and Purification of a PER.C6-Expressed IgM Antibody Therapeutic

By Christopher Valasek, Joshua Cole, Frank Hensel, Pei Ye, Michael A. Conner, and Michiel E. Ultee

Mmunoglobulin G (IgG) antibodies have been used to treat cancer for many years. Another class of antibodies — immunoglobulin M (IgM) — has been overlooked in spite of offering unique advantages that make them highly desirable as cancer therapeutics. Serving a valuable function in our innate immune system, IgM antibodies are the first to be secreted when an abnormal cell is present. These antibodies play a critical role in recognition and elimination of infectious particles, in removal of intracellular components, and in immunosurveillance mechanisms against malignant cells. IgMs also can bind to multiple copies of a target on a cancer cell surface. Such high avidity leads to cross-linking and more effective cell killing.