Quantitative measurement of full-length and C-terminal proteolyzed RBP4 in serum of normal and insulin-resistant humans using a novel mass spectrometry immunoassay.

ABSTRACT: Serum retinol-binding protein 4 (RBP4) levels are increased in insulin-resistant humans and correlate with severity of insulin resistance in metabolic syndrome. Quantitative Western blotting (qWestern) has been the most accurate method for serum RBP4 measurements, but qWestern is technically complex and labor intensive. The lack of a reliable, high-throughput method for RBP4 measurements has resulted in variability in findings in insulin-resistant humans. Many commonly used ELISAs have limited dynamic range. Neither the current ELISAs nor qWestern distinguish among full-length and carboxyl terminus proteolyzed forms of circulating RBP4 that are altered in different medical conditions. Here, we report the development of a novel quantitative mass spectrometry immunoaffinity assay (qMSIA) to

SUBMITTER: Yang Q 

PROVIDER: S-EPMC3281532 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature