Antibodies are secreted molecules of B-cells and majorly involved in immune responses against infectious diseases, or during autoimmunity, allergies, and other acute and chronic diseases. Antibodies can be distinguished into different classes and subclasses (isotypes), that have distinct functions during immune responses. Isotype-specific responses are of broad interest for biomedical research applications to decipher and optimize host immunity and protection against infection, or to mechanistically understand the pathogenesis of non-infectious diseases. Previously, we developed monoclonal antibodies (mAbs) against canine immunoglobulin M (IgM) and IgG. Our hypothesis is that canine IgG and IgM-specific mAbs will advance canine biomedical and applied research for a broad spectrum of diseases. In Aim 1, we will characterize the IgM and IgG mAbs using purified serum IgM and different IgG fractions by Western blotting and in fluorescent bead-based assays. Aim 2 is to clone and express the different IgG isotypes genes from canine peripheral blood B-cells. IgG transfectants will be stained with the individual canine IgG mAbs to determine each mAb’s IgG isotype specificity by flow cytometry. Fluorescent-bead based assays to identify canine IgM and IgG
isotypes will be developed. The project goals are to characterize new mAbs for quantification of canine IgG isotype and IgM in serum and to provide new tools to advance research and diagnostics in dogs and other canines.