title: Levels of soluble ST2 in serum associated with severity of dengue due to tumour necrosis factor alpha stimulation.
abstract: The interleukin-1 receptor-like-1 protein (IL1RL1), also known as ST2, has been shown previously to regulate T-cell function and is produced by T cells and endothelial cells. It was reported recently to be elevated in mild dengue patients during acute disease. The ST2 gene encodes several splice products: L (long), V (short) and s (soluble). A cohort of 38 patients with dengue haemorrhagic fever (DHF) and mild dengue fever (DF) were evaluated using a secreted soluble ST2 (sST2) ELISA. The RNA expression of ST2 was evaluated by real-time quantitative RT-PCR using patients' peripheral blood mononuclear cells (PBMCs) and in vitro using human umbilical vein endothelial cells (HUVECs) exposed to sera from dengue patients. DHF patients had higher levels of serum sST2, tumour necrosis factor alpha (TNF-alpha), interleukin (IL)-8 and IL-10 compared with DF patients and normal healthy control individuals. However, viraemia was indistinguishable between mild and severe cases. No changes in ST2 mRNA expression were found in PBMCs from these two groups of dengue patients. In vitro, sST2 was elevated in HUVECs treated with patient sera. Neutralization of TNF-alpha in patient sera by pre-treatment with a TNF-alpha antibody inhibited the upregulation of sST2 expression in HUVECs. These results implicate serum TNF-alpha in the modulation of expression of sST2 in an in vitro system, and indicate that sST2 could be associated with the severity of disease. Further studies to determine whether sST2 levels are predictive of the severe form of the disease and the role of sST2 in immune regulation are warranted.
authors.affiliation: Grupo de Virología, Universidad El Bosque, Bogota, Colombia.
authors.forename: Natalia
authors.initials: N
authors.lastname: Houghton-Triviño
authors.forename: Doris M
authors.initials: DM
authors.lastname: Salgado
authors.forename: Jairo A
authors.initials: JA
authors.lastname: Rodríguez
authors.forename: Irene
authors.initials: I
authors.lastname: Bosch
authors.forename: Jaime E
authors.initials: JE
authors.lastname: Castellanos
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D002460:Cell Line; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology*; D042783:Endothelial Cells / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D000072179:Interleukin-1 Receptor-Like 1 Protein; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011956:Receptors, Cell Surface / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D044967:Serum / Q000737:chemistry; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*; D055815:Young Adult
chemical_list: D015415:Biomarkers; C079241:IL1RL1 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D011956:Receptors, Cell Surface; D014409:Tumor Necrosis Factor-alpha