IgG and IgA Concentrations Determined in Serum and Milk from Atlantic Bottlenose Dolphins (Tursiops truncatus) with Monoclonal Antibodies Specific for the Immunoglobulin Isotypes
To determine concentrations of the various isotypes of immunoglobulins in serum or milk samples from Atlantic bottlenose dolphins (Tursiops truncatus), it was first necessary to produce reagents for the individual proteins. Serum and milk samples were provided by researchers working with wild dolphins and from facilities within and outside of the United States. Monoclonal antibodies were produced in this laboratory, which were specific for either the gamma heavy chain of IgG or the alpha heavy chain of IgA. The antibodies were tested not only for their specificity for the chain of individual immunoglobulins, but also for species specificity. When tested by Western blot/immunostain against IgG and IgA from Commerson's dolphin (Cephalorhynchus commersonii), Pacific white-sided dolphin (Lagenorhynchus obliquidens), killer whale (Orcinus orca), and beluga whale (Delphinapterus leucas), the monoclonal antibodies showed no cross-reactivity. When an enzyme-linked assay (ELISA) was performed, however, there was weak cross-reactivity between the anti-dolphin gamma heavy chain monoclonal antibody and the Commerson's dolphin IgG, and weak cross-reactivity between the anti-dolphin alpha heavy chain and the Commerson's dolphin IgA and Pacific white-sided dolphin IgA. Subsequently, these monoclonal antibodies were used in a competitive ELISA to determine the concentrations of IgG and IgA in the serum and milk samples.