Chromogranin A ELISA Kit (CgA)

INTENDED USE

Human chromogranin A ELISA kit is intended for determining in vitro quantitative amounts of chromogranin A (CgA, parathyroid secretory protein-1) in human serum and plasma (EDTA). This assay has a minimum sensitivity limit of 5.0 µg/l.

BACKGROUND

Chromogranin A (CgA) which can also be known as parathyroid secretory protein-1, is part of the granins (chromogranin/secretogranin) family that are found located in secretory vesicles of neurons and endocrine cells (such as islet beta cell secretory granules in pancreas). It is also a precursor to a number of functional peptides for example catestatin, pancreastatin, parastatin and vasostatin, all of these peptides have a role in negatively modulating the neuroendocrine function of autocrine and paracrine cells.

Parathyroid secretory protein-1 is now also regarded as one of the most important circulating tumour marker many kinds of neuroendocrine tumours, its concentrations are found to be elevated in neuroblastoma, gastrinoma, gastroentero-pancreatic and pheochromocytoma tumors. Chromogranin A concentrations are found to display a high correlation to the tumour mass, this has led to it being used widely in order to monitor the outcome of a number of therapies. For example, an elevation in the levels of CgA in patients having prostate carcinoma hint at an unfavourable outcome of the disease. Parathyroid secretory protein-1 is elevated in pheochromocytomas and has also been discovered as an autoantigen in type 1 diabetes.

CONTENT

All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

• Chromogranin A Microtiter Strips: Antibody precoated microwell plate in a resealable pouch with desiccant.
• Standard (A-E): Concentrations 0, 30, 110, 450, 900 µg/l.
• Control Low & High.
• Antibody Conjugate: Rabbit anti-chromogranin A antibody, conjugated with peroxidase.
• Substrate: Tetramethylbenzidine (TMB).
• Wash Buffer Concentrate (50x).
• Stop Solution: Causes severe skin burns and eye damage.

SENSITIVITY

The minimum detection sensitivity level of human chromogranin A (Parathyroid secretory protein-1 and CgA) using current CgA ELISA kit was 5.0 µg/l. The dynamic range for this assay is 30.0 – 700.0 µg/l.

ASSAY CHARACTERISTICS

– Analytical Sensitivity: Limit of Detection (LOD)(Serum 6.5 µg/l), Limit of Quantification (LOQ) (Serum 7.4 µg/l).
– Intra-Assay Variations: 4.3 – 5.6%
– Inter-Assay Variations: 9.4 –11.0%
– Recovery: 93 – 96%
– Linearity: 94 – 109%
– High-Dose-Hook Effect: No hook effect was observed in samples with concentrations higher than 200,000 µg/l Chromogranin A.

REFERENCES

1. A Critical Approach to Clinical Biochemistry of Chromogranin-A. Adv Exp Med Biol. (2015) 867: 317-23. Review. Bottoni P., et al.
2. Chromogranin A: a multifaceted cardiovascular role in health and disease. Curr Med Chem. (2012) 19 (24): 4042-50. Review. Angelone T., et al.
3. Metabolic effects and mechanism of action of the chromogranin A-derived peptide pancreastatin. Regul Pept. (2010) 161 (1-3): 8-14. Review. Sánchez-Margalet V., et al.
4. Catestatin: a multifunctional peptide from chromogranin A. Regul Pept. (2010) 162 (1-3): 33-43. Review. Mahata S.K., et al.

ADDITIONAL INFORMATION

• Full Name: Chromogranin A ELISA Kit (CgA)
• Reactivity: Human
• Sample Type: Serum, Plasma (EDTA)
• Sensitivity: 5.0 µg/l

OTHER RELATED ELISA KITS

• Alpha-Fetoprotein (AFP) ELISA Kit
• Beta-2 Microglobulin (B2M) ELISA Kit
• Neuron Specific Enolase (NSE) ELISA Kit