Single Epitope Sandwich assay for SES™

A novel immunoassay for improved sensitivity and minimal bias

B-type natriuretic peptide (Brain natriuretic peptide, BNP) is an acknowledged marker of heart failure (HF) widely used in clinical practice for HF diagnosis and patient management.                    

The majority of BNP assays are designed as sandwich-type immunoas­says utilizing two mAbs specific to distantly located epitopes. In commercially available assays at least one of these two antibodies is spe­cific to the ring structure, while the other is usu­ally specific to the C-terminus of the BNP molecule. Recent data regarding BNP instability in circulation suggests that immunoassays utilizing at least one MAb specific to the terminal epitope could underes­timate the real BNP content in the blood sample.

CLINICAL UTILITY OF BNP

• Identification or exclusion of heart failure (HF)
• Assessment of the severity of HF
• Prognosis of the disease development
• Monitoring of drug therapy in the presence of HF

BENEFITS OF SES™ -BNP ASSAY

• Equally recognizes proBNP, BNP and their truncated forms
• Enables extremely high sensitivity (1 pg/ml)
• Targeted to a stable epitope 11-17 aar of BNP

Monoclonal Antibodies

Antigens

SES™ -BNP is a trademark or a registered trademark of HyTest Ltd.

Problem – In most commercially available assays, at least one mAb is specific to the C-terminus of the BNP molecule. Since BNP in circulation is often partially truncated, this type of assay may not detect all BNP forms present in blood.

 

Solution – In our proprietary SES™ -BNP assay the capture antibody (mAb 24C5) is specific to the stable ring part of the BNP molecule. The detection antibody (mAb Ab-BNP2) is specific to the complex formed by capture antibody and BNP (or proBNP). Detection antibody does not recognize BNP or capture antibody separately, the epitope for antibody binding is only formed when these two molecules are in a complex. In the SES™ -BNP assay the accuracy and specificity are not compromised by truncation of BNP allowing reliable quantitation of the biomarker.

 

Articles:

Tamm NN, et al. (2008) Novel immunoassay for quantification of brain natriuretic peptide and its precursor in human blood. Clin Chem 54(9), 1511-8. doi: 10.1373/clinchem.2007.10054

Tamm NN, et al. (2011) Measurement of B-type natriuretic peptide by two assays utilizing antibodies with different epitope specificity. Clin Biochem 44(2-3), 257-259

Rosjo, H et al. (2012) Diagnostic utility of a single-epitope sandwich B-type natriuretic peptide assay in stable coronary artery disease: Data from the Akershus Cardiac Examination (ACE) 1 Study. Clin. Biochem. 45, 1269–1275