Chromogranin A (CGA) antibodies are immunological tools used to detect Chromogranin A, a glycoprotein widely expressed in neuroendocrine cells. CGA is a key component of secretory granules in neurons and endocrine cells, playing a role in hormone storage, secretion regulation, and granulogenesis. It is co-released with peptide hormones and neurotransmitters, making it a reliable biomarker for neuroendocrine tumors (NETs), such as pheochromocytomas, paragangliomas, and carcinoid tumors.
CGA antibodies are primarily employed in immunohistochemistry (IHC) and enzyme-linked immunosorbent assays (ELISA) to identify and quantify CGA in tissue samples or blood. Their diagnostic utility stems from CGA's high specificity for neuroendocrine differentiation, aiding in distinguishing NETs from non-neuroendocrine malignancies. Additionally, elevated serum CGA levels detected via these antibodies can indicate disease progression or recurrence.
Research also explores CGA's involvement in cardiovascular diseases, inflammatory conditions, and neurodegenerative disorders, broadening the scope of CGA antibody applications. However, factors like renal impairment or proton pump inhibitor use may affect CGA levels, requiring careful interpretation. Despite limitations, CGA antibodies remain indispensable in both clinical diagnostics and experimental studies of neuroendocrine systems.