The Dynamics of Circulating Heparin-Binding Protein: Implications for Its Use as a Biomarker

Heparin-binding protein (HBP) is a promising biomarker for the development and severity of sepsis. To guide its use, it is important to understand the factors that could lead to false-positive or negative results, such as inappropriate release and inadequate clearance of HBP. HBP is presumably released only by neutrophils, and the organs responsible for its elimination are unknown. In this study, we aimed to determine whether non-neutrophil cells can be a source of circulating HBP and which organs are responsible for its removal. We found that in two cohorts of neutropenic patients, 12% and 19% of patients in each cohort, respectively, had detectable plasma HBP levels. In vitro, three leukemia-derived monocytic cell lines and healthy CD14+ monocytes constitutively released detectable levels of HBP. When HBP was injected intravenously in rats, we found that plasma levels of HBP decreased rapidly, with a distribution half-life below 10 min and an elimination half-life of 1–2 h. We measured HBP levels in the liver, spleen, kidneys, lungs, and urine using both ELISA and immunofluorescence quantitation, and found that the majority of HBP was present in the liver, and a small amount was present in the spleen. Immunofluorescence imaging indicated that HBP is associated mainly with hepatocytes in the liver and monocytes/macrophages in the spleen. The impact of hematologic malignancies and liver diseases on plasma HBP levels should be explored further in clinical studies.

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The dynamics of circulating heparin-binding protein (HBP) - implications for its use as a biomarker

10.21203/rs.3.rs-640497/v1 ◽

2021 ◽

Author(s):

Jane Fisher ◽

Fredrik Kahn ◽

Elena Wiebe ◽

Pontus Gustafsson ◽

Thomas Kander ◽

...

Keyword(s):

Half Life ◽

Binding Protein ◽

Hematologic Malignancies ◽

Heparin Binding ◽

Monocytic Cell ◽

Negative Results ◽

Heparin Binding Protein ◽

Neutropenic Patients ◽

The Impact

Abstract Background Heparin Binding Protein (HBP) is a promising new biomarker for the development and severity of sepsis. To guide the use of HBP as a biomarker it is important to understand the factors that may lead to false positive or negative results. The mechanisms that could lead to falsely elevated HBP levels include inappropriate release and inadequate clearance of HBP by the responsible cells and organs. HBP is presumably released only by neutrophils and the organs responsible for its elimination are unknown. Therefore, in this study we aimed to determine whether non-neutrophil cells can be a source of HBP in the circulation and which organs are responsible for its removal.Results We measured HBP in two cohorts of neutropenic patients and found that 12% and 19% of patients in each cohort respectively had detectable HBP levels. In vitro, we found that three leukemia-derived monocytic cell lines and healthy CD14 + monocytes constitutively released detectable levels of HBP. Next we injected HBP intravenously in rats found that plasma levels of HBP decreased rapidly, with a distribution half-life below 10 minutes and an elimination half-life of 1–2 hours. We measured HBP levels in the liver, spleen, kidneys, lungs, and urine using both ELISA and immunofluorescence quantitation and found that the majority of HBP was present in the liver and a small amount was present in the spleen. Immunofluorescence imaging indicated that HBP is associated mainly with hepatocytes in the liver and monocytes/macrophages in the spleen.Conclusions HBP can be found in some neutropenic patients. Other than neutrophils, malignant myeloid cells and monocytic cells may be an additional source of HBP. HBP disappears rapidly from the circulation and distributes primarily to liver hepatocytes and spleen monocytes/macrophages. The impact of hematologic malignancies and liver diseases on plasma HBP levels should be explored further in clinical studies.

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Heparin-Binding Protein 17/Fibroblast Growth Factor-Binding Protein-1 Knockout Inhibits Proliferation and Induces Differentiation of Squamous Cell Carcinoma Cells

Cancers ◽

10.3390/cancers13112684 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2684

Author(s):

Tomoaki Shintani ◽

Mirai Higaki ◽

Tetsuji Okamoto

Keyword(s):

Growth Factor ◽

Fibroblast Growth Factor ◽

Squamous Cell ◽

Binding Protein ◽

Squamous Cell Carcinomas ◽

Fibroblast Growth ◽

Heparin Binding ◽

Heparin Binding Protein

Heparin-binding protein 17/fibroblast growth factor-binding protein-1 (HBp17/FGFBP-1) has been observed to induce the tumorigenic potential of epithelial cells and is highly expressed in oral cancer cell lines and tissues. It is also recognized as a pro-angiogenic molecule because of its interaction with fibroblast growth factor (FGF)-2. In this study, we examined the functional role of HBp17/FGFBP-1 in A431 and HO-1-N-1 cells. Originally, HBp17/FGFBP-1 was purified from A431 cell-conditioned media based on its capacity to bind to FGF-1 and FGF-2. We isolated and established HBp17/FGFBP-1-knockout (KO)-A431 and KO-HO-1-N-1 cell lines using the clusters of regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9) gene editing technology. The amount of FGF-2 secreted into conditioned medium decreased for A431-HBp17-KO and HO-1-N-1-HBp17-KO cells compared to their WT counterparts. Functional assessment showed that HBp17/FGFBP-1 KO inhibited cell proliferation, colony formation, and cell motility in vitro. It also inhibited tumor growth in vivo compared to controls, which confirmed the significant difference in growth in vitro between HBp17-KO cells and wild-type (WT) cells, indicating that HBp17/FGFBP-1 is a potent therapeutic target in squamous cell carcinomas (SCC) and oral squamous cell carcinomas (OSCC). In addition, complementary DNA/protein expression analysis followed by Gene Ontology and protein–protein interaction (PPI) analysis using the Database for Visualization and Integrated Discovery and Search Tool for the Retrieval of Interacting Genes/Proteins showed that both gene and protein expression related to epidermal development, cornification, and keratinization were upregulated in A431-HBp17-KO and HO-1-N-1-KO cells. This is the first discovery of a novel role of HBp17/FGFBP-1 that regulates SCC and OSCC cell differentiation.

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Possible Involvement of Heparin-Binding Protein in Antibody-Mediated Non-Hemolytic Transfusion Reaction.

Blood ◽

10.1182/blood.v110.11.4014.4014 ◽

2007 ◽

Vol 110 (11) ◽

pp. 4014-4014

Author(s):

Rika A. Furuta ◽

Kazuta Yasui ◽

Nobuki Matsuyama ◽

Yasuo Fukumori ◽

Takafumi Kimura ◽

...

Keyword(s):

Cell Activation ◽

Binding Protein ◽

Heparin Binding ◽

Human Antibodies ◽

Heparin Binding Protein ◽

Hemolytic Transfusion Reaction ◽

A Cell ◽

Cell Culture Assay ◽

Transfusion Reactions

Abstract In antibody-mediated non-hemolytic transfusion reactions, Transfusion-Related Acute Lung Injury (TRALI) tends to occur immediately after a blood transfusion. Leukocyte antibodies or immune complexes have been frequently shown to be associated with the syndrome, although the mechanisms by which they induce TRALI are poorly understood. To explore the mechanism of TRALI, an in vitro whole blood cell culture assay was established in which cells were stimulated by human antibodies and the activation of neutrophils was monitored by a cell surface marker (Mac-1) with FCM. To identify soluble mediators that were released instantly following immune stimulation, we examined the release of soluble factors, including, Perforin, IL-6, TNF-a, and Heparin binding protein (HBP) using ELISAs. In addition, the involvement of two neutrophil FcγRs (FcγRIIIb and FcγRIIa, also known as CD16 and CD32, respectively) in release of HBP was examined during antibody-induced cell activation using anti-FcγR blocking antibodies. Substantial amounts of HBP were released within 30 min upon stimulation by human antibodies, although other soluble mediators were not released within such an eary period. Furthermore, the release of HBP was mediated via signals though both FcγRIIIb and FcγRIIa. HBP that have been known as a multifunctional molecule in early inflammation appears to be a one of the primary effector molecules of antibody-mediated non-hemolytic transfusion reactions including TRALI.

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