title: Clinical utility of insulin-like growth factor 1 and 2; determination by high resolution mass spectrometry.
abstract: Measurement of insulin-like growth factor-1 (IGF-I) has utility for the diagnosis and management of growth disorders, but inter-assay comparison of results has been complicated by a multitude of reference standards, antibodies, detection methods, and pre-analytical preparation strategies. We developed a quantitative LC-MS method for intact IGF-I, which has advantages in throughput and complexity when compared to mass spectrometric approaches that rely on stable isotope dilution analysis of tryptic peptides. Since the method makes use of full-scan data, the assay was easily extended to provide quantitative measurement of IGF-II using the same assay protocol. The validated LC-MS assay for IGF-I and IGF-II provides accurate results across the pediatric and adult reference range and is suitable for clinical use.
authors.affiliation: Cleveland Heart Lab, Cleveland, Ohio, United States of America.
authors.forename: Cory
authors.initials: C
authors.lastname: Bystrom
authors.forename: Shijun
authors.initials: S
authors.lastname: Sheng
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
authors.forename: Michael
authors.initials: M
authors.lastname: Caulfield
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Clarke
authors.forename: Richard
authors.initials: R
authors.lastname: Reitz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002138:Calibration; D002648:Child; D002675:Child, Preschool; D002853:Chromatography, Liquid; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D016014:Linear Models; D008163:Luminescent Measurements; D013058:Mass Spectrometry / Q000379:methods*; D008875:Middle Aged; D011786:Quality Control; D011863:Radioimmunoassay; D051381:Rats; D012016:Reference Values; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II