ArrayExpress Uploaderarrayexpress_sidhuman242maleWhite65minLT6248maleWhite70minGTE6218femaleWhite120minLT6311femaleWhite140minGTE6176femaleWhite70minLT6222maleBlack/African American110minLT6118maleWhite100minGTE6159maleWhite120minLT6176maleBlack/African American135minGTE6187femaleWhite80minLT694femaleWhite125minGTE6216104Objective. Follistatin-like protein 1 (FSTL-1) is a secreted glycoprotein that is over-expressed in certain inflammatory diseases. Our...E-GEOD-38849/profile/8773/arrayexpressuploader511arthritiscelldiseaseerythrocyteglycoproteinjuvenile idiopathic arthritismacrophageperipheralproteinserumsyndromeDec.12, 2014Falseserum-follistatin-like-protein-1-is-a-biomarker-foE-GEOD-38849_A-AFFY-44Serum Follistatin-Like Protein 1 Is a Biomarker for Macrophage Activation Syndrome and May Predict Disease Course in Systemic Juvenile Idiopathic ArthritisJul.11, 2014Objective. Follistatin-like protein 1 (FSTL-1) is a secreted glycoprotein that is over-expressed in certain inflammatory diseases. Our objective in this study was to correlate FSTL-1 levels with measures of clinical disease activity in systemic juvenile idiopathic arthritis (sJIA), including macrophage activation syndrome (MAS). Methods. FSTL-1 serum levels were measured by ELISA in 28 patients with sJIA, including 7 patients who developed MAS, as well as in 30 normal controls. Levels were correlated with erythrocyte sedimentation rate (ESR), ferritin and sIL-2Rα expression. Differential gene expression based on FSTL-1 levels was analyzed in peripheral blood mononuclear cells (PBMCs). Results. FSTL-1 serum levels were elevated at time of presentation (pre-treatment) of sJIA (mean 200.7 ng/ml) and decreased to normal (mean 133.7 ng/ml) over 24 months (p<0.01). FSTL-1 levels were markedly elevated during acute MAS (mean 279.8 ng/ml) and decreased to normal (mean 120.3 ng/ml) following treatment (p<0.001). FSTL-1 levels correlated with serum markers of inflammation, including sIL-2Rα and ferritin, in patients with MAS. PBMCs from patients with FSTL-1 levels >200 ng/ml showed an increase in expression of genes related to innate immunity and erythropoiesis, and decrease in NK cell function. Patients with the highest FSTL-1 levels at disease onset (>300 ng/ml) ultimately required cyclosporine treatment. Conclusion. In patients with sJIA, serum FSTL-1 is a biomarker for MAS and FSTL-1 levels at presentation may predict subsequent disease course. Patients with FSTL-1 levels >200 ng/ml had altered gene expression patterns suggestive of subclinical MAS and may represent a subgroup of sJIA with more severe disease. FSTL-1 serum levels were measured by ELISA in 28 patients with sJIA, including 7 patients who developed MAS, as well as in 30 normal controls. Levels were correlated with erythrocyte sedimentation rate (ESR), ferritin and sIL-2Rα expression. Differential gene expression based on FSTL-1 levels was analyzed in peripheral blood mononuclear cells (PBMCs). Only 11 patients were run on microarray.http://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-38849http://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-38849/samples/