Emzyme-Linked Immunosorbent Assay for Detection of Canine Chromogranin A by Use of Immunological Cross-Reactivity of Rabbit Anti-Bovine Chromogranin A Antibody

Abstract

Bovine and canine chromogranin A were extracted and purified from each specie's adrenal glands. Isolated bovine 70 kDa protein showed 100% identity to bovine CgA reported previously, whereas isolated canine 68 kDa protein showed 83.3% identity to bovine CgA by the NH₂-terminal amino acid sequence analysis. Rabbit antibody to purified bovine protein (CgA) was found to immunologically cross-reatced with purified canine protein (CgA). In sandwich ELISA with anti-bovine CgA, concentration-dependent curves were obtained ranging from 0.3 to 20 μg/ml for canine CgA. From these findings, sandwich ELISA with anti-bovine CgA is found to be useful to determine the concentration of canine CgA.