title: Measurement of soluble C-type lectin-like receptor 2 in human plasma.
abstract: Detection of platelet activation in vivo is useful to identify patients at risk of thrombotic diseases. Platelet factor 4 (PF4) and β-thromboglobulin (β-TG) are used for this purpose; however, they are easily released upon the minimal platelet activation that occurs during sampling. Soluble forms of several platelet membrane proteins are released upon platelet activation; however, the soluble form of C-type lectin-like receptor 2 (sCLEC-2) has not yet been fully investigated. Western blotting with an anti-CLEC-2 antibody showed that sCLEC-2 was released from washed human platelets stimulated with collagen mimetics. To detect sCLEC-2 in plasma, we established a sandwich enzyme-linked immunosorbent assay (ELISA) using F(ab')2 anti-CLEC-2 monoclonal antibodies. Although plasma mixed with citrate, adenosine, theophylline and adenosine (CTAD) is needed for the PF4 and β-TG assays, effects of anti-coagulants (EDTA, citrate and CTAD) on the sCLEC-2 ELISA were negligible. Moreover, while special techniques are required for blood sampling and sample preparation for PF4 and β-TG assay, the standard blood collections procedures used in daily clinical laboratory tests have shown to suffice for sCLEC-2 analysis. In this study, we found that two forms of sCLEC-2 are released after platelet activation: a shed fragment and a microparticle-bound full-length protein, both of which are detected by the sCLEC-2 ELISA. The average concentration of sCLEC-2 in the plasma of 10 healthy individuals was 97 ± 55 pg/ml, whereas that in the plasma of 25 patients with diabetes mellitus (DM) was 149 ± 260 pg/ml. A trend towards an increase in sCLEC-2 concentration in the DM patients may reflect in vivo platelet activation in the patients, suggesting that sCLEC-2 may have clinical significance as a biomarker of in vivo platelet activation.
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Fuminori
authors: F
authors: Kazama
authors: b Department of Antibody Group, Narita R&D Department, Research and Development Division , LSI Medicine Corporation , Takomachi, Katori-gun , Chiba , Japan .
authors: Junya
authors: J
authors: Nakamura
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Makoto
authors: M
authors: Osada
authors: c Faculty of Medicine , Infection Control Office, University of Yamanashi Hospital, University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Osamu
authors: O
authors: Inoue
authors: b Department of Antibody Group, Narita R&D Department, Research and Development Division , LSI Medicine Corporation , Takomachi, Katori-gun , Chiba , Japan .
authors: Mitsuru
authors: M
authors: Oosawa
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .|d Japan Society for the Promotion of Science , Tokyo , Japan , and.
authors: Shogo
authors: S
authors: Tamura
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Nagaharu
authors: N
authors: Tsukiji
authors: e Department of Internal Medicine III , Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo , Yamanashi , Japan.
authors: Kaoru
authors: K
authors: Aida
authors: e Department of Internal Medicine III , Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo , Yamanashi , Japan.
authors: Akio
authors: A
authors: Kawaguchi
authors: e Department of Internal Medicine III , Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo , Yamanashi , Japan.
authors: Soichi
authors: S
authors: Takizawa
authors: e Department of Internal Medicine III , Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo , Yamanashi , Japan.
authors: Masahiro
authors: M
authors: Kaneshige
authors: e Department of Internal Medicine III , Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi , Chuo , Yamanashi , Japan.
authors: Shoichiro
authors: S
authors: Tanaka
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Katsue
authors: K
authors: Suzuki-Inoue
authors: a Department of Clinical and Laboratory Medicine, Faculty of Medicine , University of Yamanashi , Chuo , Yamanashi , Japan .
authors: Yukio
authors: Y
authors: Ozaki
mesh_terms: D015415:Biomarkers; D016022:Case-Control Studies; D003920:Diabetes Mellitus / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards; D006801:Humans; D037181:Lectins, C-Type / Q000097:blood*; D008562:Membrane Glycoproteins / Q000097:blood*; D015539:Platelet Activation; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; C104778:CLEC2B protein, human; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins
keywords: Biomarker; CLEC-2; platelet activation; platelets; thrombosis