Development and evaluation of an immuno-MALDI (iMALDI) assay for angiotensin I and the diagnosis of secondary hypertension

Clinical Proteomics

Christoph H Borchers¹  Jessica Grace van der Gugten²  Daniel T Holmes²  Robert Popp³  Alexander G Camenzind³ 

[1] Genome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaDepartment of Biochemistry and Microbiology, University of Victoria, Victoria, CanadaGenome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaGenome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaDepartment of Biochemistry and Microbiology, University of Victoria, Victoria, CanadaDepartment of Biochemistry and Microbiology, University of Victoria, Victoria, CanadaGenome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaDepartment of Biochemistry and Microbiology, University of Victoria, Victoria, Canada;Department of Pathology and Laboratory Medicine, St. Paul’s Hospital, University of British Columbia, Vancouver, CanadaDepartment of Pathology and Laboratory Medicine, St. Paul’s Hospital, University of British Columbia, Vancouver, CanadaDepartment of Pathology and Laboratory Medicine, St. Paul’s Hospital, University of British Columbia, Vancouver, Canada;Genome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaGenome British Columbia Proteomics Centre, University of Victoria, Victoria, CanadaGenome British Columbia Proteomics Centre, University of Victoria, Victoria, Canada

关键词: Hypertension;    Angiotensin-I;    Plasma renin activity;    PRA;    iMALDI;    Immuno-MALDI;   

DOI  :  10.1186/1559-0275-10-20

来源: Humana Press Inc

【 摘 要 】

Abstract

Plasma renin activity (PRA) is an essential analytical tool for screening and diagnosis of secondary forms of hypertension. Typically, PRA is measured by competitive radioimmunoassay, but there are significant drawbacks to this technique including non-specificity, long analysis times, narrow calibration range, and the requirement for radionucleotides. In this paper, we report a method for plasma renin activity determination by immuno-MALDI mass spectrometry detection. This method overcomes the issues of non-specificity and long analytical times present with RIA, and does not require the use of radionucleotides. As an initial methodological evaluation, plasma renin activity results obtained by radioimmunoassay, LC/ESI-MS/MS, and immuno-MALDI on 64 samples from an outpatient primary aldosteronism screening program have been compared. A strong correlation was found between immuno-MALDI and radioimmunoassay (R² = 0.9412, 62/64 within the 95% CI of the Bland-Altman plot), and iMALDI and LC/ESI-MS/MS (R² = 0.9471, 62/64 within the 95% CI of the Bland-Altman plot). Technical replicates showed a 4.8% CV, while inter- and intra-day replicates showed CVs of 17.3% and 17.2% respectively. We have developed an assay capable of measuring PRA without the use of radionucleotides. This immuno-MALDI approach affords the specificity of MS while avoiding the long analytical run times and technical problems associated with HPLC. With the use of robotic sample preparation to optimize precision, this assay should be adaptable to clinical environments.

【 授权许可】

Unknown