Different conformational forms of serum carnosinase detected by a newly developed sandwich ELISA for the measurements of carnosinase concentrations

• Published in: Amino acids 2012-07, Vol.43 (1), p.143-151
• Main Authors: Adelmann, Katja, Frey, Dirk, Riedl, Eva, Koeppel, Hannes, Pfister, Frederick, Peters, Verena, Schmitt, Claus P., Sternik, Paula, Hofmann, Stephanie, Zentgraf, Hans Walter, Navis, Gerjan, van den Born, Jacob, Bakker, Stephan J. L., Krämer, Bernhard K., Yard, Benito A., Hauske, Sibylle J.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Animals; Antibodies; Antibodies, Monoclonal; Assaying; Biochemical Engineering; Biochemistry; Biomedical and Life Sciences; Cell Line; Cercopithecus aethiops; Correlation; COS Cells; Dipeptidases - blood; Dipeptidases - chemistry; Dipeptidases - immunology; EDTA; ELISA; Enzyme-Linked Immunosorbent Assay - methods; Heparins; Humans; Life Sciences; Mice; Neurobiology; Original Article; Protein Conformation; Proteins; Proteomics; Serums
• ISSN: 0939-4451; 1438-2199
• DOI: 10.1007/s00726-012-1244-8

Serum carnosinase (CN-1) measurements are at present mainly performed by assessing enzyme activity. This method is time-consuming, not well suited for large series of samples and can be discordant to measurements of CN-1 protein concentrations. To overcome these limitations, we developed sandwich ELISA assays using different anti-CN-1 antibodies, i.e., ATLAS (polyclonal IgG) and RYSK173 (monoclonal IgG1). With the ATLAS-based assay, similar amounts of CN-1 were detected in serum and both EDTA and heparin plasma. The RYSKS173-based assay detected CN-1 in serum in all individuals at significantly lower concentrations compared to the ATLAS-based assay (range: 0.1–1.8 vs. 1–50 μg/ml, RYSK- vs. ATLAS-based, P