SRM/MRM targeted proteomics as a tool for biomarker validation and absolute quantification in human urine

Area of Science:

• Clinical Proteomics and Biomarker Discovery
• Analytical Chemistry and Mass Spectrometry

Background:

• Urine is a prime body fluid for clinical analysis due to its accessibility.
• Accurate quantification of protein biomarkers in urine is crucial for disease diagnosis and monitoring.
• Traditional methods like ELISA face challenges in multiplexed biomarker identification within complex biological samples.

Purpose of the Study:

• To review the workflow of selected reaction monitoring (SRM)/multiple reaction monitoring (MRM) for disease biomarker validation in urine.
• To describe the assay performance of SRM/MRM in recent clinical studies.
• To highlight targeted mass spectrometry as an alternative for validating multiple urine biomarkers simultaneously.

Main Methods:

• Utilizes targeted mass spectrometry, specifically triple quadrupole instruments.
• Employs selected reaction monitoring (SRM)/multiple reaction monitoring (MRM) mode for peptide quantification.
• Peptides serve as surrogates for absolute protein biomarker quantification in urine.

Main Results:

• Targeted mass spectrometry enables accurate and specific simultaneous quantification of multiple biomarkers (multiplexing).
• The SRM/MRM workflow provides a robust method for urine biomarker validation.
• Recent studies demonstrate the effectiveness and performance of SRM/MRM assays in clinical urine samples.

Conclusions:

• Selected reaction monitoring/multiple reaction monitoring is a powerful technique for validating disease biomarkers in urine.
• This targeted mass spectrometry approach offers advantages in multiplexing and accuracy over traditional methods.
• The described workflow and performance data support the use of SRM/MRM in clinical proteomic applications.