Long-term indoor gunshot exposure of special police forces induces bronchitic reactions and elevated blood lead levels-The Berlin shooting range study

BACKGROUND

Gunshot emissions contain toxic elements that can harm those frequently exposed, such as police officers. Several years ago, police indoor firing ranges were closed by the Berlin municipality in response to police officer health complaints, and an investigation was launched into the possible respiratory health risks of frequent gunshot emission exposure. We, therefore, conducted an exploratory cross-sectional study to investigate clinical and functional parameters of respiratory health as well as the burden of trace elements in policemen with long-term high exposure to indoor gunshot emissions, compared to low-exposure and control groups.

METHODS

We conducted lung function tests and collected blood and urine samples from Berlin police officers and government employees who were divided into three subject groups based on exposure to gunshot emissions: high exposure (n = 53), low exposure (n = 94) and no exposure (n = 76). Lung function was examined using body plethysmography. Blood and urine samples were tested via inductively coupled plasma mass spectrometry for the presence of common gunshot powder elements (antimony, lead and manganese). Exposure and symptoms were assessed using records as well as questionnaires.

RESULTS

Higher exposure was associated with more respiratory symptoms during gun shooting practice (64% vs. 21%, P < 0.001) compared to the low-exposure group. Headache, cough, discoloured mucous and shortness of breath were also more common as were some other symptoms. The cough symptomatology of the high-exposure group also persisted significantly longer (median: 0.67 vs. 0.01 days, range: 0 to 5 days, P = 0.029) compared to the low-exposure group. They also showed a lower forced expiratory volume in 1 s/forced vital capacity quotient (Tiffeneau index), P = 0.018 between the three groups and P = 0.005 for the high-exposure group, a possible marker of early, subclinical bronchial obstruction. We observed increased blood lead concentrations depending on subject's age (+1.2% per year, 95% confidence interval: 0.5-1.9%, P < 0.001) and cumulative gunshot exposure (+0.34% per 100 000 shots, 0.02-0.66%, P = 0.037).

CONCLUSIONS

These first results suggest that long-term exposure to indoor gunshot emissions induces bronchitic reactions due to repeated irritation of the airways. Higher levels of exposure lead to more negatively impacted lung function and higher blood lead levels with the possible reason that more frequent exposure may mean shorter regeneration phases for the respiratory mucous membrane. We recommend a reduction of exposure to gunshot emissions in order to decrease symptoms and avoid any-even small-deterioration in spirometry.

Patients' subjective assessment as a decisive predictor of malignancy in pelvic masses: results of a multicentric, prospective pelvic mass study

OBJECTIVE

The prognosis for ovarian cancer patients remains poor. A key to maximizing survival rates is early detection and treatment. This requires an accurate prediction of malignancy. Our study seeks to improve the accuracy of prediction by focusing on early subjective assessment of malignancy. We therefore investigated the assessment of patients themselves in comparison to the assessment of physicians.

METHODS

One thousand three hundred and thirty patients participated in a prospective and multicenter study in six hospitals in Berlin. Using univariate analysis and multivariate logistic regression models, we measured the accuracy of the early subjective assessment in comparison to the final histological outcome. Moreover, we investigated factors related to the assessment of patients and physicians.

RESULTS

The patients' assessment of malignancy is remarkably accurate. With a positive predictive value of 58%, the majority of patients correctly assessed a pelvic mass as malignant. With more information available, physicians achieved only a slightly more accurate prediction of 63%.

CONCLUSIONS

For the first time, our study considered subjective factors in the diagnostic process of pelvic masses. This paper demonstrates that the patients' personal assessment should be taken seriously as it can provide a significant contribution to earlier diagnosis and thus improved therapy and overall prognosis.

Imaging Keratan Sulfate in Ocular Tissue Sections by Immunofluorescence Microscopy and LA-ICP-MS

Carbohydrate-specific antibodies can serve as valuable tools to monitor alterations in the extracellular matrix resulting from pathologies. Here, the keratan sulfate-specific monoclonal antibody MZ15 was characterized in more detail by immunofluorescence microscopy as well as laser ablation ICP-MS using tissue cryosections and paraffin-embedded samples. Pretreatment with keratanase II prevented staining of samples and therefore demonstrated efficient enzymatic keratan sulfate degradation. Random fluorescent labeling and site-directed introduction of a metal cage into MZ15 were successful and allowed for a highly sensitive detection of the keratan sulfate landscape in the corneal stroma from rats and human tissue.

Plasma Proteome Fingerprints Reveal Distinctiveness and Clinical Outcome of SARS-CoV-2 Infection

Background: We evaluated how plasma proteomic signatures in patients with suspected COVID-19 can unravel the pathophysiology, and determine kinetics and clinical outcome of the infection. Methods: Plasma samples from patients presenting to the emergency department (ED) with symptoms of COVID-19 were stratified into: (1) patients with suspected COVID-19 that was not confirmed (n = 44); (2) non-hospitalized patients with confirmed COVID-19 (n = 44); (3) hospitalized patients with confirmed COVID-19 (n = 53) with variable outcome; and (4) patients presenting to the ED with minor diseases unrelated to SARS-CoV-2 infection (n = 20). Besides standard of care diagnostics, 177 circulating proteins related to inflammation and cardiovascular disease were analyzed using proximity extension assay (PEA, Olink) technology. Results: Comparative proteome analysis revealed 14 distinct proteins as highly associated with SARS-CoV-2 infection and 12 proteins with subsequent hospitalization (p < 0.001). ADM, IL-6, MCP-3, TRAIL-R2, and PD-L1 were each predictive for death (AUROC curve 0.80–0.87). The consistent increase of these markers, from hospital admission to intensive care and fatality, supported the concept that these proteins are of major clinical relevance. Conclusions: We identified distinct plasma proteins linked to the presence and course of COVID-19. These plasma proteomic findings may translate to a protein fingerprint, helping to assist clinical management decisions.

A Novel 29-Messenger RNA Host-Response Assay From Whole Blood Accurately Identifies Bacterial and Viral Infections in Patients Presenting to the Emergency Department With Suspected Infections: A Prospective Observational Study

OBJECTIVES

The rapid diagnosis of acute infections and sepsis remains a serious challenge. As a result of limitations in current diagnostics, guidelines recommend early antimicrobials for suspected sepsis patients to improve outcomes at a cost to antimicrobial stewardship. We aimed to develop and prospectively validate a new, 29-messenger RNA blood-based host-response classifier Inflammatix Bacterial Viral Non-Infected version 2 (IMX-BVN-2) to determine the likelihood of bacterial and viral infections.

DESIGN

Prospective observational study.

SETTING

Emergency Department, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Germany.

PATIENTS

Three hundred twelve adult patients presenting to the emergency department with suspected acute infections or sepsis with at least one vital sign change.

INTERVENTIONS

None (observational study only).

MEASUREMENTS AND MAIN RESULTS

Gene expression levels from extracted whole blood RNA was quantified on a NanoString nCounter SPRINT (NanoString Technologies, Seattle, WA). Two predicted probability scores for the presence of bacterial and viral infection were calculated using the IMX-BVN-2 neural network classifier, which was trained on an independent development set. The IMX-BVN-2 bacterial score showed an area under the receiver operating curve for adjudicated bacterial versus ruled out bacterial infection of 0.90 (95% CI, 0.85-0.95) compared with 0.89 (95% CI, 0.84-0.94) for procalcitonin with procalcitonin being used in the adjudication. The IMX-BVN-2 viral score area under the receiver operating curve for adjudicated versus ruled out viral infection was 0.83 (95% CI, 0.77-0.89).

CONCLUSIONS

IMX-BVN-2 demonstrated accuracy for detecting both viral infections and bacterial infections. This shows the potential of host-response tests as a novel and practical approach for determining the causes of infections, which could improve patient outcomes while upholding antimicrobial stewardship.

The need for cardiac surgery differential tariffs in Israel at the era of aging population and emerging technology: Importance of procedure type and patient complexity as assessed by EuroSCORE

Background

Reimbursement for cardiac surgical procedures in Israel is uniform and does not account for diversity in costs of various procedures or for diversity in patient mix. In an era of new and costly technology coupled with higher risk patients needing more complex surgery, these tariffs may not adequately reflect the true financial burden on the caregivers. In the present study we attempt to determine whether case mix and complexity of procedures significantly affect cost to justify differential tariffs.

Methods

We included all patients undergoing cardiac surgery at Shaare Zedek Medical Center between the years 1993–2016. Patients were stratified according to (1) type of surgery and (2) clinical profile as reflected by the predicted operative risk according to the European System for Cardiac Operative Risk Evaluation (EuroSCORE). Approximate cost of each group of patients was estimated by the average number of days in the Intensive Care Unit and days in the postoperative ward multiplied by the respective daily costs as determined by the Ministry of Health. We then added the fixed cost of the components used in the operating room (manpower and disposables). The final estimated cost (the outcome variable) was then evaluated as it relates to type of surgery and clinical profile. ANOVA was used to analyze cost variability between groups, and backward regression analysis to determine the respective effect of the abovementioned variables on cost. Because of non-normal distribution, both costs and lengths of stay were Log-transformed.

Results

Altogether there were 5496 patients: 3863, 836, 685 and 112 in the isolated CABG, CABG + valve, 1 valve and 2 valves replacement groups. By ANOVA, the costs in all EuroSCORE subgroups were significantly different from each other, increasing with increased EuroSCORE subgroup. Cost was also significantly different among procedure groups, increasing from simple CABG to single valve surgery to CABG + valve surgery to 2-valve surgery. In backward stepwise multiple regression analysis, both type of procedure and EuroSCORE group significantly impacted cost. ICU stay and Ward stay were significantly but weakly related while EuroSCORE subgroup was highly predictive of both ICU stay and ward stay.

Conclusions

The cost of performing heart surgery today is directly influenced by both patient profile as well as type of surgery, both of which can be quantified. Modern day technology is costly yet has become mandatory. Thus reimbursement for heart surgery should be based on differential criteria, namely clinical risk profile as well as type of surgery. Our results suggest an urgent need for design and implementation of a differential tariff model in the Israeli reimbursement system. We suggest that a model using a fixed, average price according to the type of procedure costs, in addition to a variable hospitalization cost (ICU + ward) determined by the patient EuroSCORE or EuroSCORE subgroup should enable an equitable reimbursement to hospitals, based on their case mix.

Glycosylation is a key in SARS-CoV-2 infection

SARS-CoV-2 causes the respiratory syndrome COVID-19 and is responsible for the current pandemic. The S protein of SARS-CoV-2-mediating virus binding to target cells and subsequent viral uptake is extensively glycosylated. Here we focus on how glycosylation of both SARS-CoV-2 and target cells crucially impacts SARS-CoV-2 infection at different levels: (1) virus binding and entry to host cells, with glycosaminoglycans of host cells acting as a necessary co-factor for SARS-CoV-2 infection by interacting with the receptor-binding domain of the SARS-CoV-2 spike glycoprotein, (2) innate and adaptive immune response where glycosylation plays both a protective role and contributes to immune evasion by masking of viral polypeptide epitopes and may add to the cytokine cascade via non-fucosylated IgG, and (3) therapy and vaccination where a monoclonal antibody-neutralizing SARS-CoV-2 was shown to interact also with a distinct glycan epitope on the SARS-CoV-2 spike protein. These evidences highlight the importance of ensuring that glycans are considered when tackling this disease, particularly in the development of vaccines, therapeutic strategies and serological testing.

Delayed Antibody and T-Cell Response to BNT162b2 Vaccination in the Elderly, Germany

We detected delayed and reduced antibody and T-cell responses after BNT162b2 vaccination in 71 elderly persons (median age 81 years) compared with 123 healthcare workers (median age 34 years) in Germany. These data emphasize that nonpharmaceutical interventions for coronavirus disease remain crucial and that additional immunizations for the elderly might become necessary.

A Matter of Caution: Coagulation Parameters in COVID-19 Do Not Differ from Patients with Ruled-Out SARS-CoV-2 Infection in the Emergency Department

COVID-19 (coronavirus disease 2019) patients often show excessive activation of coagulation, associated with increased risk of thrombosis. However, the diagnostic value of coagulation at initial clinical evaluation is not clear. We present an in-depth analysis of coagulation in patients presenting to the emergency department (ED) with suspected COVID-19. N  = 58 patients with clinically suspected COVID-19 in the ED were enrolled. N  = 17 subsequently tested positive using SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) polymerase chain reaction (PCR) swabs, while in n  = 41 COVID-19 was ruled-out. We analyzed both standard and extended coagulation parameters, including thromboplastin time (INR), activated partial thromboplastin time (aPTT), antithrombin, plasminogen, plasminogen activator inhibitor-1 (PAI-1), D-dimers, and fibrinogen at admission, as well as α2-antiplasmin, activated protein C -resistance, factor V, lupus anticoagulant, protein C, protein S, and von Willebrand diagnostics. These data, as well as mortality and further laboratory parameters, were compared across groups based on COVID-19 diagnosis and severity of disease. In patients with COVID-19, we detected frequent clotting abnormalities, including D-dimers. The comparison cohort in the ED, however, showed similarly altered coagulation. Furthermore, parameters previously shown to distinguish between severe and moderate COVID-19 courses, such as platelets, plasminogen, fibrinogen, aPTT, INR, and antithrombin, as well as multiple nonroutine coagulation analytes showed no significant differences between patients with and without COVID-19 when presenting to the ED. At admission to the ED the prevalence of coagulopathy in patients with COVID-19 is high, yet comparable to the non-COVID-19 cohort presenting with respiratory symptoms. Nevertheless, coagulopathy might worsen during disease progression with the need of subsequent risk stratification.

Assessment of serum ferritin as a biomarker in COVID-19: bystander or participant? Insights by comparison with other infectious and non-infectious diseases

BACKGROUND

The 2019 coronavirus disease (COVID-19) caused by the SARS-CoV-2 virus has an impact on all aspects of patient care. Serum ferritin generally represents a biomarker of choice when iron deficiency is suspected. However, ferritin is also an acute-phase-protein exhibiting elevated serum concentration in various inflammatory diseases. Here we focus on the role of serum ferritin for diagnostic and clinical management of patients with COVID-19 in comparison with other infectious and non-infectious diseases.

METHODS

We examined scientific articles listed in PubMed reporting on ferritin in various infectious and non-infectious diseases. We then compared these results with nine current COVID-19 ferritin reports published in 2020.

RESULTS

Several non-infectious, as well as non-COVID-19 infectious diseases, are characterised by a partly dramatic elevation of serum ferritin levels. All COVID-19 studies published between February and May 2020, which documented laboratory serum ferritin, indicate ferritin as a biomarker of COVID-19 severity in hospitalised patients.

CONCLUSIONS

Serum ferritin may be considered both a prognostic and stratifying biomarker that can also contribute to therapeutic decision-making concerning patients with COVID-19. It should be emphasised, however, that most scientific reports refer to cohorts in the Asian region. Further validation in other cohorts is urgently required.

Severe COVID-19 Is Marked by a Dysregulated Myeloid Cell Compartment

Coronavirus disease 2019 (COVID-19) is a mild to moderate respiratory tract infection, however, a subset of patients progress to severe disease and respiratory failure. The mechanism of protective immunity in mild forms and the pathogenesis of severe COVID-19 associated with increased neutrophil counts and dysregulated immune responses remain unclear. In a dual-center, two-cohort study, we combined single-cell RNA-sequencing and single-cell proteomics of whole-blood and peripheral-blood mononuclear cells to determine changes in immune cell composition and activation in mild versus severe COVID-19 (242 samples from 109 individuals) over time. HLA-DRhiCD11chi inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DRlo monocytes. Our study provides detailed insights into the systemic immune response to SARS-CoV-2 infection and reveals profound alterations in the myeloid cell compartment associated with severe COVID-19.

Pooling, room temperature, and extended storage time increase the release of adult-specific biologic response modifiers in platelet concentrates: a hidden transfusion risk for neonates?

BACKGROUND

Adult donor platelets (PLTs) are frequently transfused to prevent or stop bleeding in neonates with thrombocytopenia. There is evidence for PLT transfusion-related morbidity and mortality, leading to the hypothesis on immunomodulatory effects of transfusing adult PLTs into neonates. Candidate factors are biologic response modifiers (BRMs) that are expressed at higher rates in adult than in neonatal PLTs. This study investigated whether storage conditions or preparation methods impact on the release of those differentially expressed BRMs.

STUDY DESIGN AND METHODS

Pooled PLT concentrates (PCs) and apheresis PCs (APCs) were stored under agitation for up to 7 days at room temperature (RT) or at 2 to 8°C. The BRMs CCL5/RANTES, TGFβ1, TSP1, and DKK1 were measured in PCs' supernatant, lysate, and corresponding plasma. PLT function was assessed by light transmission aggregometry.

RESULTS

Concerning the preparation method, higher concentrations of DKK1 were found in pooled PCs compared to APCs. In supernatants, the concentrations of CCL5, TGFβ1, TSP1, and DKK1 significantly increased, both over standard (≤4 days) and over extended storage times (7 days). Each of the four BRMs showed an up to twofold increase in concentration after storage at RT compared to cold storage (CS). There was no difference in the aggregation capacity.

CONCLUSION

This analysis shows that the release of adult-specific BRMs during storage is lowest in short- and CS APCs. Our study points to strategies for reducing the exposure of sick neonates to BRMs that can be specifically associated to PLT transfusion-related morbidity.

Underfilling of vacuum blood collection tubes leads to increased lactate dehydrogenase activity in serum and heparin plasma samples

Background Lactate dehydrogenase (LD) activity is routinely monitored for therapeutic risk stratification of malignant diseases, but is also prone to preanalytical influences. Methods We systematically analyzed the impact of defined preanalytical conditions on the hemolysis-susceptible parameters LD, potassium (K) and hemolysis index in vacuum blood collection tubes (serum [SE], heparin plasma [HP]). Blood was collected by venipuncture from healthy volunteers. Tubes were either filled or underfilled to approximately 50%, then processed directly or stored at room temperature for 4 h. Potassium (K), sodium (Na), chloride (Cl), LD, creatine kinase (CK), total cholesterol, and indices for hemolysis, icterus, and lipemia were analyzed. Filling velocity was determined in a subset of tubes. Findings in healthy volunteers were reconfirmed in an in-patient cohort (n = 74,751) that was analyzed for plasma yield and LD data distribution. Results LD activity was higher in HP compared to SE. Underfilling led to higher LD values (SE: +21.6%; HP: +28.3%), K (SE: +4.2%; HP: +5.3%), and hemolysis index (SE: +260.8%; HP: +210.0%), while other analytes remained largely unchanged. Filling velocity of tubes was approximately 3-fold higher in the first half compared to the second half in both HP and SE collection tubes. Importantly, plasma yield also inversely correlated with LD in routine patients. By calculating reference limits, the lowest plasma yield quartile of the patient cohort displayed LD values clearly exceeding current reference recommendations. Conclusions Underfilling of tubes leads to a higher proportion of blood aspirated with high velocity and relevant elevations in LD. This finding should be considered in cases of clinically implausible elevated LD activities.

Platelet-derived growth factor receptor β activation and regulation in murine myelofibrosis

There is prevailing evidence to suggest a decisive role for platelet-derived growth factors (PDGF) and their receptors in primary myelofibrosis. While PDGF receptor β (PDGFRβ) expression is increased in bone marrow stromal cells of patients correlating with the grade of myelofibrosis, knowledge on the precise role of PDGFRβ signaling in myelofibrosis is sparse. Using the Gata-1^low mouse model for myelofibrosis, we applied RNA sequencing, protein expression analyses, multispectral imaging and, as a novel approach in bone marrow tissue, an in situ proximity ligation assay to provide a detailed characterization of PDGFRβ signaling and regulation during development of myelofibrosis. We observed an increase in PDGFRβ and PDGF-B protein expression in overt fibrotic bone marrow, along with an increase in PDGFRβ–PDGF-B interaction, analyzed by proximity ligation assay. However, PDGFRβ tyrosine phosphorylation levels were not increased. We therefore focused on regulation of PDGFRβ by protein tyrosine phosphatases as endogenous PDGFRβ antagonists. Gene expression analyses showed distinct expression dynamics among PDGFRβ-targeting phosphatases. In particular, we observed enhanced T-cell protein tyrosine phosphatase protein expression and PDGFRβ–T-cell protein tyrosine phosphatase interaction in early and overt fibrotic bone marrow of Gata-1^low mice. In vitro, T-cell protein tyrosine phosphatase (Ptpn2) knockdown increased PDGFRβ phosphorylation at Y⁷⁵¹ and Y¹⁰²¹, leading to enhanced downstream signaling in fibroblasts. Furthermore, Ptpn2 knockdown cells showed increased growth rates when exposed to low-serum growth medium. Taken together, PDGF signaling is differentially regulated during myelofibrosis. Protein tyrosine phosphatases, which have so far not been examined during disease progression, are novel and hitherto unrecognized components in myelofibrosis.

Kidney Injury after Intravenous versus Intra-arterial Contrast Agent in Patients Suspected of Having Coronary Artery Disease: A Randomized Trial

Background In the absence of randomized studies, it has been controversial whether the likelihood of acute kidney injury (AKI) differs between intravenous and intra-arterial contrast agent administration. Purpose To compare intravenous versus intra-arterial contrast agent administration in relationship to AKI and analyze the association between AKI and chronic kidney disease (defined as at least mildly decreased estimated glomerular filtration rates [eGFRs]). Materials and Methods This was a prospective study (ClinicalTrials.gov: NCT00844220) that involved randomizing participants with atypical chest pain and suspected coronary artery disease (CAD) between February 2009 and August 2015 to undergo coronary CT angiography with intravenous contrast agent administration or cardiac catheterization angiography with intra-arterial contrast agent administration. This prespecified secondary analysis compared AKI (serum creatinine increase of ≥ 25% or 0.5 mg/dL after 18-24 or 46-50 hours) determined by blinded investigators using absolute differences and relative risks, including two-sided 95% confidence intervals (CIs). Results A total of 320 participants (163 [50.9%] women; mean age, 60 years ± 11) were included. Baseline eGFR did not differ between the CT angiography group (84.3 mL/min/1.73 m² ± 17.2) and the catheterization group (87.1 mL/min/1.73 m² ± 16.7) (P = .14). AKI occurred in nine of 161 participants in the CT angiography group (5.6%; 95% CI: 3%, 10%) and in 21 of 159 participants in the catheterization group (13.2%; 95% CI: 9%,19%) (relative risk, 2.4; 95% CI: 1.1, 5.0; P = .02). Also in the subgroup of participants without obstructive CAD, in those not requiring coronary interventions, AKI was more common in the catheterization group (11.9%; 95% CI: 8%, 19%) than in the CT angiography group (4.3% [95% CI: 2%, 9%]; difference, 7.7% [95% CI: 1.3%, 14.1%]; relative risk, 2.8 [95% CI: 1.1, 7.0]; P = .02). Obstructive CAD (odds ratio [OR]: 2.7 [95% CI: 1.1, 6.6]; P = .02), femoral catheter access (OR: 2.5 [95% CI: 1.1, 5.6]; P = .04), and cine ventriculography were associated with AKI (OR: 2.3 [95% CI: 1.0, 4.9]; P = .03). In multivariable analysis, the presence of postcontrast AKI was associated with chronic kidney disease (hazard ratio: 12.4 [95% CI: 4.5, 34.6]; P < .01). Conclusion Acute kidney injury was more common after cardiac catheterization than after CT angiography in this prospective randomized study of patients suspected of having coronary artery disease. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Einstein and Newhouse in this issue.

The effect of blood sampling and preanalytical processing on human N-glycome

Glycome modulations have been described in the onset and progression of many diseases. Thus, many studies have proposed glycans from blood glycoproteins as disease markers. Astonishingly, little effort has been given unraveling preanalytical conditions potentially influencing glycan analysis prior to blood biomarker studies. In this work, we evaluate for the first time the effect of hemolysis, storage and blood collection, but also influence of various times and temperatures between individual processing steps on the total N-glycome and on a glycan-biomarker score. Venous blood was collected from 10 healthy donors in 11 blood collection tubes with different additives, processed variously to obtain 16 preanalytical variables and N-glycans released from serum or plasma were analyzed by MALDI-TOF-MS and capillary electrophoresis coupled with fluorescence detection (CE-LIF) for the first time. Long time storage of deep frozen samples at -20°C or -80°C exerted only a minor influence on the glycome as demonstrated by CE-LIF. The N-glycome was very stable evidenced by MALDI-TOF when stored at 4°C for at least 48 hours and blood collected in tubes devoid of additives. The glycome was stable upon storage after centrifugation and aliquoting, which is an important information considering future diagnostic applications. Hemolysis, however, negatively correlated with an established glycan score for ovarian cancer, when evaluated by MALDI-TOF-MS measurement by affecting relative intensities of certain glycans, which could lead to false negative / positive results in glycan biomarker studies.

Use of Hepatocytes in Adhesion and Suspension Cultures for Liver Support Bioreactors

Hepatocyte cultivation in bioreactors for hybrid liver support systems is possible under two conditions: attached to a substrate like membranes or microcarriers or in suspension culture. To compare the ammonia metabolism of hepatocytes cultivated under these two conditions, cultures of primary seeded rat hepatocytes were cultivated either attached to collagen coated tissue culture plastic or as a suspension culture.

During the time course of culture, the ability of hepatocytes to reduce the ammonia content of the medium decreased in both adhesion and suspension cultures, though to different extents.

In suspension cultures, ammonia content was reduced from 350 μM to about 100 μM (day 4) and to about 180 μM (day 6). No significant reduction was seen on day 8 of culture. In contrast, hepatocytes attached to collagen coated dishes remained viable and functional for at least 8 days after plating, reducing ammonia content from 350 μM to 70 μM (day 4), 90 μM (day 6) and 180 μM (day 8). The period of useful metabolism of hepatocytes in bioreactors for hybrid liver support systems appears to depend on the culture conditions

[PSMA-targeted radioligand therapy in prostate cancer]

Radioligand therapy (RLT) directed against prostate-specific membrane antigen (PSMA) enables tumor-specific treatment directed against PSMA-overexpressing prostate cancer cells. Several PSMA ligands such as PSMA-617 or PSMA-I&T have been developed that can be labeled with β‑radiating lutetium-177. These are currently applied in compassionate use programs to treat metastatic castration-resistant prostate cancer (mCRPC). PSMA-directed RLT is currently being offered in several nuclear medicine departments throughout Germany. Several retrospective case series demonstrate its activity with a prostate-specific antigen (PSA) decrease >50% in 30-60% of mCRPC patients. The toxicity seems to be low. Hematologic grade 4 toxicity has not been observed and grade 3 toxicities rarely occur. The main nonhematologic adverse events are intermittent dry mouth because of unspecific PSMA expression in the salivary glands as well as fatigue and nausea. Currently there are no prospective studies available for evaluation of PSMA-targeted RLT and a survival benefit over approved standard therapies such as abiraterone, enzalutamide, radium-223-dichloride, docetaxel or cabazitaxel has not been shown. PSMA-targeted RLT should therefore currently only be offered after critical evaluation in patients who exhausted the approved standard therapies.

Reducing Macro- and Microheterogeneity of N-Glycans Enables the Crystal Structure of the Lectin and EGF-Like Domains of Human L-Selectin To Be Solved at 1.9 Å Resolution

L-Selectin, a cell-adhesion receptor on the surface of most leukocytes, contains seven N-glycosylation sites. In order to obtain the crystal structure of human L-selectin, we expressed a shortened version of L-selectin comprising the C-type lectin and EGF-like domains (termed LE) and systematically analysed mutations of the three glycosylation sites (Asn22, Asn66 and Asn139) in order to reduce macroheterogeneity. After we further removed microheterogeneity, we obtained crystals that diffracted X-rays up to 1.9 Å from a variant (LE010) with exchanges N22Q and N139Q and one GlcNAc₂ Man₅ N-glycan chain attached to Asn66. Crystal-structure analysis showed that the terminal mannose of GlcNAc₂ Man₅ of one LE010 molecule was coordinated to Ca²⁺ in the binding site of a symmetry-related LE010. The orientation of the lectin and EGF-like domain was similar to the described "bent" conformation of E- and P-selectins. The Ca²⁺ -binding site reflects the binding mode seen in E- and P-selectin structures co-crystallised with ligands.

The Cell-Surface N-Glycome of Human Embryonic Stem Cells and Differentiated Hepatic Cells thereof

Human embryonic stem cells (hESCs) are pluripotent stem cells that offer a wide range of applications in regenerative medicine. In addition, they have been proposed as an appropriate alternative source of hepatocytes. In this work, hESCs were differentiated into definitive endodermal cells (DECs), followed by maturation into hepatocyte-like cells (HLCs). Their cell-surface N-glycome was profiled and also compared with that of primary human hepatocytes (PHHs). Undifferentiated hESCs contained large amounts of high-mannose N-glycans. In contrast, complex-type N-glycans such as asialylated or monosialylated biantennary and triantennary N-glycans were dominant in HLCs, and fully galactosylated structures were significantly more abundant than in undifferentiated hESCs. The cell-surface N-glycosylation of PHHs was more biologically processed than that of HLCs, with bisialylated biantennary and trisialylated triantennary structures predominant. This is the first report of the cell surface N-glycome of PHHs and of HLCs being directly generated from hESCs without embryoid body formation.

High incidence of cardiac dysfunction and response to antiviral treatment in patients with chronic hepatitis C virus infection

AIMS

Hepatitis C virus (HCV) has been associated with cardiomyopathies. Former anti-HCV therapies employing interferon could have serious side effects in patients with advanced heart failure since interferon may adversely impact upon cardiac function. We, therefore, examined whether the novel, interferon-free and highly virus-selective anti-HCV combination therapy might be applicable even in advanced or end-stage heart failure.

METHODS AND RESULTS

In a retrospective series of HCV-positive patients admitted to our institution with suspected cardiac disease, coronary, valvular or hypertensive heart disease was diagnosed in 70/146 (47.9%). Among the others, 36/76 (47.4%) had myocardial disease: LV (32.9%)/RV (13.2%) hypertrophy, RV dysfunction (13.2%)/dilation (6.6%), severe diastolic dysfunction (7.9%), pulmonary hypertension (22.4%). One critically ill patient listed for heart transplantation (HTX) had previously not tolerated an interferon-based protocol. To still improve her chance of enduring transplant survival, we attempted an interferon-free virus-selective antiviral combination drug protocol under careful monitoring of possible side effects. Regarding clinical status she tolerated this treatment well, with the exception of transient severe hyponatremia requiring substitution. Her NYHA functional class improved from II-IV before to class II immediately after successful complete HCV elimination.

CONCLUSIONS

Whereas prevalence of cardiac dysfunction and potential benefit from antiviral treatment was reported previously, there is lack of data regarding the response of patients with advanced heart failure. Since the highly HCV-selective drugs used above do not eliminate other cardiotropic viruses and have no direct effect on inflammation, massive improvement in such critically ill patients indicates a causal role of HCV in their cardiac failure, and of HCV elimination in their functional recovery.

[Bone-specific therapy with radium-223 dichloride : Castration-resistant prostate cancer with symptomatic bone metastases]

Radium-223 dichloride (Xofigo®, Alpharadin) is approved for the treatment of metastatic castration-resistant prostate cancer with symptomatic bone metastases and no known visceral metastases. As a calcium mimetic, it is integrated into osteoplastic bone lesions and emits alpha particles with high energy which leads to local destruction of tumor cells. In the 2013 published ALSYMPCA trial, a significant advantage for overall survival and quality of life in comparison to placebo was found. Recent data suggest an increased potential in combination with next generation hormonal treatment.

Structural requirements of mono- and multivalent L-selectin blocking aptamers for enhanced receptor inhibition in vitro and in vivo

L-selectin mediates extravasation of leukocytes from blood into the surrounding tissue during inflammation and is therefore a therapeutical target in certain overwhelming immune reactions. In this study, we characterized an L-selectin specific blocking DNA aptamer with respect to nucleotide composition and target binding. Introduction of deletions and nucleotide exchanges resulted in an optimized DNA sequence but preservation of the IC50 in the low nanomolar range. The inhibitory potential was significantly increased when the aptamer was displayed as a di- and trimer connected via appropriate linker length. Similar to monoclonal antibodies, trimer yielded picomolar IC50 values in a competitive binding assay. In comparison to the monovalent aptamer, the trivalent assembly reduced PBMC interactions to L-selectin ligands 90-fold under shear and exerted superior inhibition of PBMC rolling in vivo. In conclusion, our work demonstrates the feasibility of optimizing aptamer sequences and shows that multivalent ligand presentation enables superior adhesion receptor targeting.

FROM THE CLINICAL EDITOR

During inflammation, leukocytes extravasate from blood vessels under chemotaxic signals. The presence of L-selectin on endothelium acts as a mediator for the extravasation process. In this study, the authors investigated an L-selectin specific blocking DNA aptamer in various forms, as inhibitors to leukocyte binding and extravasation. This new approach confirmed the potential use of aptamers in clinical setting.

Rapid analysis of cell surface N-glycosylation from living cells using mass spectrometry

Cell surfaces are covered with a dense carbohydrate layer referred to as the glycocalyx. Because different cell types express different glycan signatures, it is of paramount importance to have robust methods to analyze the glycome of living cells. To achieve this, a common procedure involves cell lysis and extraction of membrane (glyco)proteins and yields a major proportion of high-mannose N-glycans that most likely stem from intracellular proteins derived from the ER. Using HEK 293 cells as a model system, we developed a reproducible, sensitive, and fast method to profile surface N-glycosylation from living cells. We directly released glycopeptides from cell surfaces through tryptic digestion of freshly harvested and vital cells, thereby improving the detection and quantification of complex-type N-glycans by increasing their relative amount from 14 to 85%. It was also possible to detect 25 additional structures in HEK 293, 48 in AGE1.HN, 42 in CHO-K1, and 51 in Hep G2 cells. The additional signals provided deeper insight into cell-type-specific N-glycan features such as antennarity, fucosylation, and sialylation. Thus, this protocol, which can potentially be applied to any cells, will be useful in the fields of glycobiotechnology and biomarker discovery.

Improving compliance to colorectal cancer screening using blood and stool based tests in patients refusing screening colonoscopy in Germany

BACKGROUND

Despite strong recommendations for colorectal cancer (CRC) screening, participation rates are low. Understanding factors that affect screening choices is essential to developing future screening strategies. Therefore, this study assessed patient willingness to use non-invasive stool or blood based screening tests after refusing colonoscopy.

METHODS

Participants were recruited during regular consultations. Demographic, health, psychological and socioeconomic factors were recorded. All subjects were advised to undergo screening by colonoscopy. Subjects who refused colonoscopy were offered a choice of non-invasive tests. Subjects who selected stool testing received a collection kit and instructions; subjects who selected plasma testing had a blood draw during the office visit. Stool samples were tested with the Hb/Hp Complex Elisa test, and blood samples were tested with the Epi proColon® 2.0 test. Patients who were positive for either were advised to have a diagnostic colonoscopy.

RESULTS

63 of 172 subjects were compliant to screening colonoscopy (37%). 106 of the 109 subjects who refused colonoscopy accepted an alternative non-invasive method (97%). 90 selected the Septin9 blood test (83%), 16 selected a stool test (15%) and 3 refused any test (3%). Reasons for blood test preference included convenience of an office draw, overall convenience and less time consuming procedure.

CONCLUSIONS

97% of subjects refusing colonoscopy accepted a non-invasive screening test of which 83% chose the Septin9 blood test. The observation that participation can be increased by offering non-invasive tests, and that a blood test is the preferred option should be validated in a prospective trial in the screening setting.

Identification of 34 N-glycan isomers in human serum by capillary electrophoresis coupled with laser-induced fluorescence allows improving glycan biomarker discovery

Alterations in glycosylation have been observed in many human diseases and specific changes in glycosylation have been proposed as relevant diagnostic information. Capillary electrophoresis coupled with laser-induced fluorescence (CE-LIF) is a robust method to quantify desialylated N-glycans that are labeled with 8-aminopyrene-1,3,6-trisulfonic acid prior to analysis. To date, only a maximum of 12 glycan structures, the most abundant ones, have been identified by CE-LIF to characterize glycome modulations of total serum in the course of the diseases. In most forms of cancer, findings using CE-LIF were limited to the increase of triantennary structures carrying a Lewis(x) epitope. In this work, we identified 32 linkage and positional glycan isomers in healthy human serum using exoglycosidase digestions as well as standard glycoproteins, for which we report the assignment of novel structures. It was possible to identify and quantify 34 glycan isomers in the serum of primary epithelial ovarian cancer patients (EOC). Reduced levels of diantennary structures and of high-mannose 5 were statistically significant in the EOC samples, and also, elevated branching as well as increased antennary fucosylation were observed. For the first time, we could demonstrate that not only antennary fucosylation was of relevance in tetraantennary structures but also core-fucosylated tetraantennary N-glycans were statistically increased in EOC patients. The results of the current study provide an improved dataset to be used in glycan biomarker discovery.

N-glycosylation profile of undifferentiated and adipogenically differentiated human bone marrow mesenchymal stem cells: towards a next generation of stem cell markers

Mesenchymal stem cells (MSCs) are multipotent cells that are easy to isolate and expand, develop into several tissues, including fat, migrate to diseased organs, have immunosuppressive properties and secrete regenerative factors. This makes MSCs ideal for regenerative medicine. For application and regulatory purposes, knowledge of (bio)markers characterizing MSCs and their development stages is of paramount importance. The cell surface is coated with glycans that possess lineage-specific nature, which makes glycans to be promising candidate markers. In the context of soft tissue generation, we aimed to identify glycans that could be markers for MSCs and their adipogenically differentiated progeny. MSCs were isolated from human bone marrow, adipogenically stimulated for 15 days and adipogenesis was verified by staining the lipid droplets and quantitative real time polymerase chain reaction of the marker genes peroxisome proliferator-activated receptor gamma (PPARG) and fatty acid binding protein-4 (FABP4). Using matrix-assisted laser desorption-ionization-time of flight mass spectrometry combined with exoglycosidase digestions, we report for the first time the N-glycome of MSCs during adipogenic differentiation. We were able to detect more than 100 different N-glycans, including high-mannose, hybrid, and complex N-glycans, as well as poly-N-acetyllactosamine chains. Adipogenesis was accompanied by an increased amount of biantennary fucosylated structures, decreased amount of fucosylated, afucosylated tri- and tetraantennary structures and increased sialylation. N-glycans H6N5F1 and H7N6F1 were significantly overexpressed in undifferentiated MSCs while H3N4F1 and H5N4F3 were upregulated in adipogenically differentiated MSCs. These glycan structures are promising candidate markers to detect and distinguish MSCs and their adipogenic progeny.

Genotoxic effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in HL-60 cells are not reproducible

Conflicting results have been published regarding the induction of genotoxic effects by exposure to radiofrequency electromagnetic fields (RF-EMF). Various results indicating a genotoxic potential of RF-EMF were reported by the collaborative EU-funded REFLEX (Risk Evaluation of Potential Environmental Hazards From Low Energy Electromagnetic Field Exposure Using Sensitive in vitro Methods) project. There has been a long-lasting scientific debate about the reliability of the reported results and an attempt to reproduce parts of the results obtained with human fibroblasts failed. Another part of the REFLEX study was performed in Berlin with the human lymphoblastoid cell line HL-60; genotoxic effects of RF-EMF were measured by means of the comet assay and the micronucleus test. The plausibility and reliability of these results were also questioned. In order to contribute to a clarification of the biological significance of the reported findings, a repeat study was performed, involving scientists of the original study. Comet-assay experiments and micronucleus tests were performed under the same experimental conditions that had led to genotoxic effects in the REFLEX study. Here we report that the attempts to reproduce the induction of genotoxic effects by RF-EMF in HL-60 cells failed. No genotoxic effects of RF-EMF were measured in the repeat experiments. We could not find an explanation for the conflicting results. However, the negative repeat experiments suggest that the biological significance of genotoxic effects of RF-EMF reported by the REFLEX study should be re-assessed.

Serum glycome profiling: a biomarker for diagnosis of ovarian cancer

During the development of cancer, changes in cellular glycosylation are observed, indicating that alterations of the glycome occur in extracellular fluids as well as in serum and could therefore serve as tumor biomarkers. In the case of epithelial ovarian cancer (EOC), common tumor markers such as CA125 are known to have poor specificity; therefore, better biomarkers are needed. The aim of this work was to identify new potential glycan biomarkers in EOC-patients. N-Glycans were cleaved from serum glycoproteins from 63 preoperative primary EOC-patients along with 33 age-matched healthy women, permethylated, and analyzed using MALDI-TOF mass spectrometry. A value named GLYCOV was calculated from the relative areas of the 11 N-glycan biomarkers revealed by SPSS statistical analyses, namely four high-mannose and seven complex-type fucosylated N-glycans. GLYCOV diagnosed primary EOC with a sensitivity of 97% and a specificity of 98.4% whereas CA-125 showed a sensitivity of 97% and a specificity of 88.9%. Our study is the first one to compare glycan values with the established tumor marker CA125 and to give better results. Therefore, the N-glycome could potentially be used as a biomarker.

CK2-dependent phosphorylation of occludin regulates the interaction with ZO-proteins and tight junction integrity

Background

Casein kinase 2 (CK2) is a ubiquitously expressed Ser/Thr kinase with multiple functions in the regulation of cell proliferation and transformation. In targeting adherens and tight junctions (TJs), CK2 modulates the strength and dynamics of epithelial cell-cell contacts. Occludin previously was identified as a substrate of CK2, however the functional consequences of CK2-dependent occludin phosphorylation on TJ function were unknown.

Results

Here, we present evidence that phosphorylation of a Thr400-XXX-Thr404-XXX-Ser408 motif in the C-terminal cytoplasmic tail of human occludin regulates assembly/disassembly and barrier properties of TJs. In contrast to wildtype and T400A/T404A/S408A-mutated occludin, a phospho-mimetic Occ-T400E/T404E/S408E construct was impaired in binding to ZO-2. Interestingly, pre-phosphorylation of a GST-Occ C-terminal domain fusion protein attenuated binding to ZO-2, whereas, binding to ZO-1 was not affected. Moreover, Occ-T400E/T404E/S408E showed delayed reassembly into TJs in Ca²⁺-switch experiments. Stable expression of Occ-T400E/T404E/S408E in MDCK C11 cells augments barrier properties in enhancing paracellular resistance in two-path impedance spectroscopy, whereas expression of wildtype and Occ-T400A/T404A/S408A did not affect transepithelial resistance.

Conclusions

These results suggest an important role of CK2 in epithelial tight junction regulation. The occludin sequence motif at amino acids 400–408 apparently represents a hotspot for Ser/Thr-kinase phosphorylation and depending on the residue(s) which are phosphorylated it differentially modulates the functional properties of the TJ.

Development and analysis of alpha 1-antitrypsin neoglycoproteins: the impact of additional N-glycosylation sites on serum half-life

Therapeutic efficacy of glycoproteins is affected by many factors, including molecular size and net charge; both are influenced by the presence and composition of glycan structures. Human alpha 1-antitrypsin (A1AT) was cloned and expressed in human embryonic kidney cells (HEK293) that are capable of mammalian glycosylation. Utilizing PCR-based site-directed mutagenesis, new A1AT variants were created with single, double, or triple additional N-glycosylation sites to the three naturally occurring N-glycosylation sites. Because of the supplementary N-glycans, the A1AT variants exhibited an increased molecular weight. Retention of inhibitory activity was shown via trypsin inhibitory assay. The A1AT variants were treated with PNGase F, and the resulting N-glycans were analyzed by MALDI-TOF mass spectrometry. The N-glycan profile of the recombinant A1AT variants was mostly composed of monofucosylated bi-, tri-, and tetraantennary complex-type N-glycans, with a tendency toward higher antennary structures compared to the wild-type. The relevance of N-glycosylation in A1AT for the circulatory serum half-life was demonstrated in CD1 mice. The A1AT neoglycoprotein with an additional N-glycosylation site at position N123 exhibited a 62% increase in serum half-life. Additionally, using a two-compartment model, the A1AT variants exhibited increased α-phase values, especially N123 (223%) and N201 (255%). The results suggest the recombinant A1AT neoglycoprotein as a serious alternative to A1AT derived from human plasma.

Changes of serum glycome in patients suffering from ovarian cancer

5047

Background: Protein glycosylation plays an important role in many biological processes. Most human serum proteins, with the exception of albumin, are glycosylated. Glycosylation is known to be altered with development of diseases such as cancer. In the case of ovarian cancer, tumor markers among them CA-125 that are clinically used are known to have poor specificity. In addition, they fail to detect the disease at an early stage. Therefore, better biomarkers are needed. The aim of the present research work is to identify new potential glycan biomarkers by analyzing the serum N-glycome of patients suffering from ovarian cancer Methods: Serum was collected from 67 patients as well as from 33 healthy age-matching women. N-glycans were released from 10 ul serum by PNGase F digestion, permethylated and subsequently analyzed by means of MALDI-TOF mass spectrometry. The SPSS software was used for the statistical analysis. Results: The N-glycome of patients was found to have more fucosylated structures, especially in tri- and tetraantennary sialylated glycans. The PCA analysis indicates that there are significant differences between the glycome of ovarian cancer patients in all stages of the disease and the glycome of healthy controls. We identified 14 potential structures that were divided in two categories, one of monofucosylated structures with high antennarity (sensitivity 94%, specificity 97%) and one containing high-mannose structures and an asialylated structures (sensitivity 97%, specificity 97%). Conclusions: Our study is the first trial to identify major differences between ovarian cancer sera and control sera, which could potentially be used in the future as biomarkers.

L-selectin--a dynamic regulator of leukocyte migration

The leukocytic cell adhesion receptor L-selectin mediates the initial step of the adhesion cascade, the capture and rolling of leukocytes on endothelial cells. This event enables leukocytes to migrate out of the vasculature into surrounding tissues during inflammation and immune surveillance. Distinct domains of L-selectin contribute to proper leukocyte migration. In this review, we discuss the contributions of these domains with respect to L-selectin function: the regulation by serine phosphorylation of the cytoplasmic tail, the role of the transmembrane domain in receptor positioning on the cell surface as well as the N-glycosylation of the extracellular part and the identification of novel binding partners.