Amylin antibodies frequently display cross-reactivity with CGRP: characterization of eight amylin antibodies.

Amylin is a 37 amino acid endocrine hormone secreted from the pancreas in response to nutrient intake, acting centrally to promote meal ending satiation. With many studies linking amylin action to the nervous system, determining the distribution or expression of amylin in the nervous system is critical. However, amylin shares sequence identity and structural homology to the related neuropeptide calcitonin-gene related peptide (CGRP). This creates challenges in identifying selective amylin antibodies that do not cross-react with CGRP, especially in neural tissues, where CGRP is densely packed into secretory vesicles. Here, we characterized eight amylin antibodies to determine their ability to detect amylin and cross-react with rat or human αCGRP, using immunoblots and pre-absorption controls in rat pancreas. We observed that amylin antibodies frequently cross-reacted with αCGRP and are therefore not suitable for use in tissues which highly express CGRP. Prior work using these antibodies should be revisited in light of our findings.