Interlaboratory reproducibility of selective reaction monitoring assays using multiple upfront analyte enrichment strategies.
Over the past few years, mass spectrometry has emerged as a technology to complement and potentially replace standard immunoassays in routine clinical core laboratories. Application of mass spectrometry to protein and peptide measurement can provide advantages including high sensitivity, the ability to multiplex analytes, and high specificity at the amino acid sequence level. In our previous study, we demonstrated excellent reproducibility of mass spectrometry-selective reaction monitoring (MS-SRM) assays when applying standardized standard operating procedures (SOPs) to measure synthetic peptides in a complex sample, as lack of reproducibility has been a frequent criticism leveled at the use of mass spectrometers in the clinical laboratory compared to immunoassays. Furthermore, an important caveat of SRM-based assays for proteins is that many low-abundance analytes require some type of enrichment before detection with MS. This adds a level of complexity to the procedure and the potential for irreproducibility increases, especially across different laboratories with different operators. The purpose of this study was to test the interlaboratory reproducibility of SRM assays with various upfront enrichment strategies and different types of clinical samples (representing real-world body fluids commonly encountered in routine clinical laboratories). Three different, previously published enrichment strategies for low-abundance analytes and a no-enrichment strategy for high-abundance analytes were tested across four different laboratories using different liquid chromatography-SRM (LC-SRM) platforms and previously developed SOPs. The results demonstrated that these assays were indeed reproducible with coefficients of variation of less than 30% for the measurement of important clinical proteins across all four laboratories in real world samples.
Thermo Fisher Scientific, BRIMS (Biomarker Research in Mass Spectrometry), Cambridge, Massachusetts 02139, United States. amol.prakash@thermofisher.com
Amol
A
Prakash
Taha
T
Rezai
Bryan
B
Krastins
David
D
Sarracino
Michael
M
Athanas
Paul
P
Russo
Hui
H
Zhang
Yuan
Y
Tian
Yan
Y
Li
Vathany
V
Kulasingam
Andrei
A
Drabovich
Christopher R
CR
Smith
Ihor
I
Batruch
Paul E
PE
Oran
Claudia
C
Fredolini
Alessandra
A
Luchini
Lance
L
Liotta
Emanuel
E
Petricoin
Eleftherios P
EP
Diamandis
Daniel W
DW
Chan
Randall
R
Nelson
Mary F
MF
Lopez
D000595:Amino Acid Sequence; D001774:Blood Chemical Analysis / Q000592:standards*; D056148:Chromatography, Reverse-Phase; D005260:Female; D019382:Human Growth Hormone / Q000652:urine; D006801:Humans; D007753:Laboratories / Q000592:standards*; D057230:Limit of Detection; D008297:Male; D013058:Mass Spectrometry / Q000592:standards*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood; D012015:Reference Standards; D015203:Reproducibility of Results; D029589:Seminal Plasma Proteins / Q000737:chemistry
D010446:Peptide Fragments; D029589:Seminal Plasma Proteins; D019382:Human Growth Hormone; D017430:Prostate-Specific Antigen