Circulating Concentrations of Follistatin-Like 1 in Healthy Individuals and Patients with Acute Coronary Syndrome as Assessed by an Immunoluminometric Sandwich Assay

摘要: Background: Follistatin-like 1 (FSTL1) is a 308–amino acid secreted glycoprotein. Tissue levels of FSTL1 are induced in animal models and patients with chronic inflammatory cardiovascular disease. We hypothesized that can be measured the human circulation used as biomarker acute coronary syndrome (ACS). Methods: developed an immunoluminometric assay (ILMA), assessed preanalytic characteristics FSTL1, determined circulating concentrations 120 apparently healthy individuals 216 ACS. Results: The had limit detection 0.17 μg/L, quantification 1.02 intraassay imprecision ≤12.7%, interassay ≤15.4%. Selectivity was demonstrated size-exclusion chromatography lack cross-reactivity related proteins. not appreciably influenced by unrelated biological substances. serum or whole blood stable at room temperature for 48 h resistant to 4 freeze-thaw cycles. Measured citrated plasma heparin-treated were 18% 17% lower, respectively, than serum. Apparently presented median concentration 7.18 (range 1.06–18.49) μg/L. Serum increased ACS risk all-cause mortality during follow-up. Conclusions: ILMA permits plasma. expect favorable reference limits defined here will facilitate future studies various disease settings, including ACS.