title: Evaluation and Validation of the Detection of soluble Triggering Receptor Expressed on Myeloid Cells 1 by Enzyme-linked immunosorbent Assay.
abstract: Triggering receptor expressed on myeloid cells (TREM)-1 plays an important role in innate immune responses and is upregulated under infectious as well as non-infectious conditions. In addition, a soluble TREM-1 variant (sTREM-1) is detectable in sera or bronchoalveolar-lavage fluids from patients. Currently, various studies are difficult to compare, since the methods of detection by enzyme-linked immunosorbent assays (ELISA) vary among different research groups. In this study, we compared three different s-TREM-1 specific ELISAs and identified individual assay characteristics finding notable differences in sTREM-1 concentrations in part depending on the employed buffers. Investigating potential confounding factors for sTREM-1 detection, serum heat-inactivation (HI) showed improved recovery compared to non-HI (NHI) serum, reproducible by addition of complement and re-heat-inactivation. Hence we identified complement as a heat-sensitive confounder in some sTREM-1 ELISAs. We conclude that it is difficult to directly compare data of several studies, in particular if different ELISAs are engaged. Immunoassays for research use only are in general hampered by lack of standardization. Further standardization is needed until sTREM-1 ELISA is capable for better reproducibility of studies and clinical application.
authors.affiliation: IIIrd Department of Medicine, Johannes-Gutenberg University Medical Center, Mainz, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Hasibeder
authors.affiliation: Center for Thrombosis and Haemostasis, Johannes-Gutenberg University Medical Center, Mainz, Germany.
authors.forename: Pamela
authors.initials: P
authors.lastname: Stein
authors.affiliation: R&D department, Hycult Biotech, Uden, The Netherlands.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Brandwijk
authors.affiliation: Institute of Immunology, Johannes-Gutenberg University Medical Center, Mainz, Germany.
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Schild
authors.affiliation: IIIrd Department of Medicine, Johannes-Gutenberg University Medical Center, Mainz, Germany.
authors.forename: Markus P
authors.initials: MP
authors.lastname: Radsak
mesh_terms: D015415:Biomarkers; D003165:Complement System Proteins / Q000378:metabolism; D015986:Confounding Factors, Epidemiologic; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008562:Membrane Glycoproteins / Q000097:blood*; D020033:Protein Isoforms; D011971:Receptors, Immunologic / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000073871:Triggering Receptor Expressed on Myeloid Cells-1
chemical_list: D015415:Biomarkers; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D011971:Receptors, Immunologic; C408842:TREM1 protein, human; D000073871:Triggering Receptor Expressed on Myeloid Cells-1; D003165:Complement System Proteins