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.

Application Value of Blood Heparin-Binding Protein in the Diagnosis of Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Objective. To investigate the expression and clinical significance of serum heparin-binding protein (HBP), C-reactive protein (CRP), and white blood cell count (WBC) in an acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods. A prospective research model was used to select 63 patients with acute exacerbation of chronic obstructive pulmonary disease who were hospitalized in Xuzhou First People’s Hospital from January 2020 to June 2020, and among the chronic obstructive pulmonary disease patients who were followed up in our hospital during the same period, 18 patients were in the stable phase, and 43 healthy patients in our hospital during the same period were selected as the healthy control group. 18 patients with stable chronic obstructive pulmonary disease were selected as the observation group, and 43 healthy people who underwent examination at the same time as the control group. For patients with acute COPD recombination, 5 ml of venous blood was collected according to whether the condition of COPD patients with acute exacerbation was stable or not. 5 ml of venous blood was collected for acute exacerbation. According to their clinical symptoms (such as cough, sputum, and asthma), dyspnea score (MRC score), and pulmonary function (FEV1 and FEV1/FVC), it is determined whether the patient’s condition is stable. Patients in the stable COPD group will collect 5 ml of venous blood during the outpatient follow-up, and those in the healthy physical examination group will collect veins on the day of the physical examination. In 5 ml of blood, the levels of HBP and CRP in the blood were measured by the enzyme-linked immunosorbent method and the immunoturbidimetric method, respectively, and the peripheral blood WBC was measured by a blood cell analyzer and its supporting reagents. The differences of the three indicators in each group were statistically analyzed. Normally distributed measurement data were compared using t-test, homogeneity of variance of nonnormally distributed measurement data were compared using one-way analysis of variance, uneven variance of nonnormally distributed measurement data were compared using a rank-sum test, and Pearson linear analysis was used for correlation test. Subject working characteristic curve (ROC) was drawn, P < 0.05 means the difference is statistically significant, the receiver working characteristic curve was established, and the area under the curve (AUC) was calculated to analyze blood HBP. The value of blood CRP and peripheral blood WBC counts alone or in combination in the diagnosis of acute exacerbations of chronic obstructive pulmonary disease. Results. The level of blood heparin-binding protein in the acute exacerbation phase was significantly higher than that in the stable phase and healthy controls ( P < 0.05 ). In the acute exacerbation stage and stable stage group, the blood heparin binding protein, the percentage of leukocytes, neutrophils, and CRP were detected. There is a correlation between ( P < 0.05 ) and a correlation with lung function (FEV1) ( P < 0.05 ). The predictive value of heparin-binding protein, white blood cells, neutrophil percentage, CRP, etc. for the acute exacerbation of chronic obstructive pulmonary disease, with the area under the heparin-binding protein curve, is the largest, and compared with the stable phase, the comparison of heparin-binding protein, white blood cells, and CRP is statistically significant ( P < 0.05 ). Conclusion. Heparin-binding protein increases in the stable phase and acute exacerbation phase and is related to other inflammatory factors. It is one of the important inflammatory factors in chronic obstructive pulmonary disease. Heparin-binding protein, white blood cells, CRP, etc. have diagnostic and predictive value for acute exacerbation of chronic obstructive pulmonary disease. Heparin-binding protein has the best predictive result, and the combined index test has a better diagnostic predictive value, which is better than single index detection.

Heparin-Binding Protein in Critically Ill Children With Severe Community-Acquired Pneumonia

Objective: The aim of this study was to investigate possible associations between Heparin-binding protein (HBP) and the development of respiratory failure (RF) and sepsis in critically ill children with severe community-acquired pneumonia (CAP).Methods: This study enrolled 157 children with severe CAP admitted to Intensive Care Unit (ICU). At ICU admission, the levels of HBP and other biomarkers, including C-reactive protein, interleukin-6 (IL-6), procalcitonin, white blood cells, neutrophil percentage, and D-dimer, were determined.Results: Of the enrolled patients, 106 developed RF (35 with RF at enrollment and 71 with RF after enrollment), while 51 did not developed RF. The number of patients progressing to sepsis in those with or without RF were 34 (21 with severe sepsis) and 14, respectively. The plasma level of HBP at admission was more than eightfold higher than the upper normal value. HBP, IL-6, and D-dimer could significantly predict the development of RF, and a high level of HBP (odds ratio = 1.008, 95% confidence interval: 1.003–1.013) was independently associated with the development of RF in this population. Compared with other biomarkers, HBP was the best indicator of progression to severe sepsis, with an area under the receiver operating characteristic curve of 0.85, the best specificity at 96.30%, and a positive predictive value of 92.86% at the optimal cut-off value of 340.29 ng/mL. The HBP level was also positively correlated with other conventional biomarkers.Conclusion: HBP might represent a better predictor of disease progression in children with severe CAP than currently used biomarkers.

Heparin-binding protein is significantly increased in acute pancreatitis

Background Most patients with acute pancreatitis (AP) experience mild, self-limiting disease with little or no need for hospital care. However, 20–25% of patients develop a more severe and potentially life-threatening condition with progressive systemic inflammatory response syndrome (SIRS) and multiorgan failure, resulting in high morbidity and mortality rates. Predicting disease severity at an early stage is important, as immediate supportive care has been demonstrated to reduce the incidence of SIRS and organ failure, improving patient outcome. Several studies have demonstrated elevated levels of heparin-binding protein (HBP) in patients with sepsis and septic shock, and HBP is believed to play a part in endothelial dysfunction leading to vascular leakage. As HBP levels increase prior to other known biomarkers, HBP has emerged as a promising early predictor of severe sepsis with organ dysfunction. Methods Patients admitted to Skåne University Hospital in Malmö between 2010 and 2013 fulfilling the criteria for AP were identified in the emergency department and prospectively enrolled in this study. The primary outcome was measured levels of HBP upon hospital admission in patients with confirmed AP. Correlations among HBP concentrations, disease severity and fluid balance were considered secondary endpoints. The correlation between HBP levels and fluid balance were analysed using Pearson correlation, and the ability of HBP to predict moderately severe/severe AP was assessed using a receiver operating characteristic (ROC) curve. Results The overall median HBP level in this study was 529 (307–898) ng/ml. There were no significant group differences in HBP levels based on AP severity. Fluid balance differed significantly between patients with mild versus moderately severe and severe pancreatitis, but we found no correlation between HBP concentration and fluid balance. Conclusions HBP levels are dramatically increased in patients with AP, and these levels far exceed those previously reported in other conditions. In this study, we did not observe any significant correlation between HBP levels and disease severity or the need for intravenous fluid. Additional studies on HBP are needed to further explore the role of HBP in the pathogenesis of AP and its possible clinical implications.

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

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.