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van der Zande HJ, Gonzalez MA, de Ruiter K, Wilbers RH, García‐Tardón N, van Huizen M, van Noort K, Pelgrom LR, Lambooij JM, Zawistowska‐Deniziak A, Otto F, Ozir‐Fazalalikhan A, van Willigen D, Welling M, Poles J, van Leeuwen F, Hokke CH, Schots A, Yazdanbakhsh M, Loke P, Guigas B. The helminth glycoprotein omega-1 improves metabolic homeostasis in obese mice through type 2 immunity-independent inhibition of food intake. FASEB J 2021; 35:e21331. [PMID: 33476078 PMCID: PMC7898285 DOI: 10.1096/fj.202001973r] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/27/2020] [Accepted: 12/14/2020] [Indexed: 02/06/2023]
Abstract
Type 2 immunity plays an essential role in the maintenance of metabolic homeostasis and its disruption during obesity promotes meta-inflammation and insulin resistance. Infection with the helminth parasite Schistosoma mansoni and treatment with its soluble egg antigens (SEA) induce a type 2 immune response in metabolic organs and improve insulin sensitivity and glucose tolerance in obese mice, yet, a causal relationship remains unproven. Here, we investigated the effects and underlying mechanisms of the T2 ribonuclease omega-1 (ω1), one of the major S mansoni immunomodulatory glycoproteins, on metabolic homeostasis. We show that treatment of obese mice with plant-produced recombinant ω1, harboring similar glycan motifs as present on the native molecule, decreased body fat mass, and improved systemic insulin sensitivity and glucose tolerance in a time- and dose-dependent manner. This effect was associated with an increase in white adipose tissue (WAT) type 2 T helper cells, eosinophils, and alternatively activated macrophages, without affecting type 2 innate lymphoid cells. In contrast to SEA, the metabolic effects of ω1 were still observed in obese STAT6-deficient mice with impaired type 2 immunity, indicating that its metabolic effects are independent of the type 2 immune response. Instead, we found that ω1 inhibited food intake, without affecting locomotor activity, WAT thermogenic capacity or whole-body energy expenditure, an effect also occurring in leptin receptor-deficient obese and hyperphagic db/db mice. Altogether, we demonstrate that while the helminth glycoprotein ω1 can induce type 2 immunity, it improves whole-body metabolic homeostasis in obese mice by inhibiting food intake via a STAT6-independent mechanism.
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Affiliation(s)
| | - Michael A. Gonzalez
- Department of MicrobiologyNew York University School of MedicineNew YorkNYUSA
| | - Karin de Ruiter
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Ruud H.P. Wilbers
- Department Laboratory of NematologyWageningen University and ResearchWageningenThe Netherlands
| | - Noemí García‐Tardón
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Mariska van Huizen
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Kim van Noort
- Department Laboratory of NematologyWageningen University and ResearchWageningenThe Netherlands
| | - Leonard R. Pelgrom
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Joost M. Lambooij
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Anna Zawistowska‐Deniziak
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
- Witold Stefański Institute of ParasitologyPolish Academy of SciencesWarsawPoland
| | - Frank Otto
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | | | - Danny van Willigen
- Interventional Molecular Imaging LaboratoryDepartment of RadiologyLeiden University Medical CenterLeidenThe Netherlands
| | - Mick Welling
- Interventional Molecular Imaging LaboratoryDepartment of RadiologyLeiden University Medical CenterLeidenThe Netherlands
| | - Jordan Poles
- Department of MicrobiologyNew York University School of MedicineNew YorkNYUSA
| | - Fijs van Leeuwen
- Interventional Molecular Imaging LaboratoryDepartment of RadiologyLeiden University Medical CenterLeidenThe Netherlands
| | - Cornelis H. Hokke
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - Arjen Schots
- Department Laboratory of NematologyWageningen University and ResearchWageningenThe Netherlands
| | - Maria Yazdanbakhsh
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
| | - P'ng Loke
- Department of MicrobiologyNew York University School of MedicineNew YorkNYUSA
- Laboratory of Parasitic DiseasesNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Bruno Guigas
- Department of ParasitologyLeiden University Medical CenterLeidenThe Netherlands
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Wasser MNJM, Welling M, Lamers G, Pauwels EKJ, Nieuwenhuizen W. Effects of an Antifibrin Monoclonal Antibody and Fragments thereof on Some Properties of Fibrin. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1645683] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryAntifibrin monoclonal antibody Y22, of IgG1-subclass, has its epitope in the D-domain of fibrin. In a thrombin time assay, Y22 and its F(ab)2 fragments interfere with clotting of citrated plasma. Transmission and scanning electronmicroscopic studies show that clotting of citrated blood or plasma in the presence of Y22 results in formation of thin, short fibrin fibres. The (smaller) Fab fragments of Y22 did not have an anti-clotting effect. This suggests that the anticoagulant effect of Y22 is due to steric hindrance of the association of fibrin monomers. A control antibody and its F(ab)2 and Fab fragments have no effect on fibrin formation.In a parabolic rate assay, Y22 Fab fragments interfered strongly with the fibrin-induced enhancement of the t-PA-catalyzed plasminogen activation, whereas intact Y22 and a control antibody did not. In contrast with their effects on the fibrin assembly, the effects of Y22, Y22-F(ab)2 and Y22-Fab on the capacity of fibrin to act as a rate-enhancer in the plasminogen activation by t-PA appears to decrease with the size of the immunoreactive entity. As is discussed, this may be due to the differential accessibility of sites involved in stimulation and polymerization which are located in the fibrin D-domain.
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Affiliation(s)
- M N J M Wasser
- The Gaubius Institute TNO, Leiden, The Netherlands
- The Department of Diagnostic Radiology, University Hospital Leiden, The Netherlands
| | - M Welling
- The Gaubius Institute TNO, Leiden, The Netherlands
- The Department of Diagnostic Radiology, University Hospital Leiden, The Netherlands
| | - G Lamers
- The Department of Cell Biology, Zoological Faculty, State University Leiden, The Netherlands
| | - E K J Pauwels
- The Department of Diagnostic Radiology, University Hospital Leiden, The Netherlands
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Eck A, Zintgraf LM, de Groot EFJ, de Meij TGJ, Cohen TS, Savelkoul PHM, Welling M, Budding AE. Interpretation of microbiota-based diagnostics by explaining individual classifier decisions. BMC Bioinformatics 2017; 18:441. [PMID: 28978318 PMCID: PMC5628491 DOI: 10.1186/s12859-017-1843-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 09/21/2017] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The human microbiota is associated with various disease states and holds a great promise for non-invasive diagnostics. However, microbiota data is challenging for traditional diagnostic approaches: It is high-dimensional, sparse and comprises of high inter-personal variation. State of the art machine learning tools are therefore needed to achieve this goal. While these tools have the ability to learn from complex data and interpret patterns therein that cannot be identified by humans, they often operate as black boxes, offering no insight into their decision-making process. In most cases, it is difficult to represent the learning of a classifier in a comprehensible way, which makes them prone to be mistrusted, or even misused, in a clinical environment. In this study, we aim to elucidate microbiota-based classifier decisions in a biologically meaningful context to allow their interpretation. RESULTS We applied a method for explanation of classifier decisions on two microbiota datasets of increasing complexity: gut versus skin microbiota samples, and inflammatory bowel disease versus healthy gut microbiota samples. The algorithm simulates bacterial species as being unknown to a pre-trained classifier, and measures its effect on the outcome. Consequently, each patient is assigned a unique quantitative estimation of which species in their microbiota defined the classification of their sample. The algorithm was able to explain the classifier decisions well, demonstrated by our validation method, and the explanations were biologically consistent with recent microbiota findings. CONCLUSIONS Application of a method for explaining individual classifier decisions for complex microbiota analysis proved feasible and opens perspectives on personalized therapy. Providing an explanation to support a microbiota-based diagnosis could guide decisions of clinical microbiologists, and has the potential to increase their confidence in the outcome of such decision support systems. This may facilitate the development of new diagnostic applications.
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Affiliation(s)
- A Eck
- Department of Medical Microbiology and Infection Control, VU University medical center, Amsterdam, The Netherlands.
| | - L M Zintgraf
- Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - E F J de Groot
- Department of Gastroenterology and Hepatology, VU University medical center, Amsterdam, The Netherlands
| | - T G J de Meij
- Department of Pediatric Gastroenterology, VU University medical center, Amsterdam, The Netherlands
| | - T S Cohen
- Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands
| | - P H M Savelkoul
- Department of Medical Microbiology and Infection Control, VU University medical center, Amsterdam, The Netherlands.,Department of Medical Microbiology, Maastricht University medical center, Maastricht, The Netherlands
| | - M Welling
- Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands.,Canadian Institute for Advanced Research, Toronto, Canada
| | - A E Budding
- Department of Medical Microbiology and Infection Control, VU University medical center, Amsterdam, The Netherlands
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Brouwer C, Vu T, Zhou M, Cardinali G, Welling M, Wiele N, Robert V. Current Opportunities and Challenges of Next Generation Sequencing (NGS) of DNA; Determining Health and Diseases. ACTA ACUST UNITED AC 2016. [DOI: 10.9734/bbj/2016/25662] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Perona P, Weber M, Welling M. Unsupervised learning of object classes from natural scenes. J Vis 2010. [DOI: 10.1167/1.3.419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Welling M, Ferro-Flores G, Pirmettis I, Brouwer C. Current Status of Imaging Infections with Radiolabeled Anti-Infective Agents. ACTA ACUST UNITED AC 2009. [DOI: 10.2174/187152109788680180] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Brouwer C, Sarda-Mantel L, Meulemans A, Guludec D, Welling M. The Use of Technetium-99m Radiolabeled Human Antimicrobial Peptides for Infection Specific Imaging. Mini Rev Med Chem 2008; 8:1039-52. [DOI: 10.2174/138955708785740670] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Affiliation(s)
- Mick Welling
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center (LUMC), Leiden, The Netherlands
- Albinusdreef 2, Leiden, Zuid-Holland 2300 rc The Netherlands
| | - Marcel Stokkel
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Jenny Balter
- Centro Investigaciones Nucleares, University of the Republic Uruguay, Montevideo, Uruguay
| | - Laure Sarda-Mantel
- AP-HP, Groupe Hospitalier Bichat-Beaujon, Service de Médecine Nucléaire, Paris, France
| | - Alain Meulemans
- AP-HP, Groupe Hospitalier Bichat-Beaujon, Service de Médecine Nucléaire, Paris, France
| | - Dominique Le Guludec
- AP-HP, Groupe Hospitalier Bichat-Beaujon, Service de Médecine Nucléaire, Paris, France
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Gomes CMF, Welling M, Que I, Henriquez NV, van der Pluijm G, Romeo S, Abrunhosa AJ, Botelho MF, Hogendoorn PCW, Pauwels EKJ, Cleton-Jansen AM. Functional imaging of multidrug resistance in an orthotopic model of osteosarcoma using 99mTc-sestamibi. Eur J Nucl Med Mol Imaging 2007; 34:1793-803. [PMID: 17541583 DOI: 10.1007/s00259-007-0480-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Accepted: 04/16/2007] [Indexed: 11/26/2022]
Abstract
PURPOSE The purpose of this work was the development of an orthotopic model of osteosarcoma based on luciferase-expressing tumour cells for the in vivo imaging of multidrug resistance (MDR) with (99m)Tc-sestamibi. METHODS Doxorubicin-sensitive (143B-luc(+)) and resistant (MNNG/HOS-luc(+)) osteosarcoma cell lines expressing different levels of P-glycoprotein and carrying a luciferase reporter gene were inoculated into the tibia of nude mice. Local tumour growth was monitored weekly by bioluminescence imaging and X-ray. After tumour growth, a (99m)Tc-sestamibi dynamic study was performed. A subset of animals was pre-treated with an MDR inhibitor (PSC833). Images were analysed for calculation of (99m)Tc-sestamibi washout half-life (t (1/2)), percentage washout rate (%WR) and tumour/non-tumour (T/NT) ratio. RESULTS A progressively increasing bioluminescent signal was detected in the proximal tibia after 2 weeks. The t (1/2) of (99m)Tc-sestamibi was significantly shorter (p < 0.05) in drug-resistant MNNG/HOS-luc(+) tumours (t (1/2) = 87.3 +/- 15.7 min) than in drug-sensitive 143B-luc(+) tumours (t (1/2) = 161.0 +/- 47.4 min) and decreased significantly with PSC833 (t (1/2) = 173.0 +/- 24.5 min, p < 0.05). No significant effects of PSC833 were observed in 143B-luc(+) tumours. The T/NT ratio was significantly lower (p < 0.05) in MNNG/HOS-luc(+) tumours than in 143B-luc(+) tumours at early (1.55 +/- 0.22 vs 2.14 +/- 0.36) and delayed times (1.12 +/- 0.11 vs 1.62 +/- 0.33). PSC833 had no significant effects on the T/NT ratios of either tumour. CONCLUSION The orthotopic injection of tumour cells provides an animal model suitable for functional imaging of MDR. In vivo bioluminescence imaging allows the non-invasive monitoring of tumour growth. The kinetic analysis of (99m)Tc-sestamibi washout provides information on the functional activity of MDR related to P-glycoprotein expression and its pharmacological inhibition in osteosarcoma.
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Affiliation(s)
- Célia M F Gomes
- Department of Radiology, Section of Nuclear Medicine, Leiden University Medical Center, Leiden, The Netherlands.
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van Hensbergen Y, Schipper LF, Brand A, Slot MC, Welling M, Nauta AJ, Fibbe WE. Ex vivo culture of human CD34+ cord blood cells with thrombopoietin (TPO) accelerates platelet engraftment in a NOD/SCID mouse model. Exp Hematol 2006; 34:943-50. [PMID: 16797422 DOI: 10.1016/j.exphem.2006.04.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 04/04/2006] [Accepted: 04/10/2006] [Indexed: 11/21/2022]
Abstract
OBJECTIVES Hematopoietic recovery, in particular platelet reconstitution, can be severely delayed after transplantation with cord blood (CB) stem cells (SC). Expansion of CB SC may be one way to improve the recovery, but there is concern that ex vivo expansion compromises the repopulating ability of SC. METHODS We used a short-term expansion protocol with TPO as single growth factor. The expanded cells were tested in the NOD/SCID mouse model and both platelet recovery and repopulation capacity were examined and compared with unexpanded CD34+ CB cells of the same CB donor. RESULTS Platelet recovery started 1 week earlier in mice transplanted with TPO-expanded CD34+ cells and at days 5 and 8 after transplantation, 6.2 +/- 2.6 and 13.9 +/- 6.7 plt/microL were observed, respectively. At similar time intervals 0.0 and 1.5 +/- 0.2 plt/microL respectively were detected in mice receiving the unmanipulated CD34+ grafts. This was accompanied by a higher number of CFU-Mk in the bone marrow (BM) 7 days after transplantation. Moreover, the BM engraftment and the lineage differentiation of human cells at 6 weeks after transplantation was similar, suggesting that long-term engraftment was not compromised by the expansion procedure. CONCLUSION Ex vivo expansion with TPO as single growth factor results in an accelerated platelet recovery in NOD/SCID mice and appears not to affect the long-term repopulation capacity.
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Thompson RI, Welling M, Schuessler HA, Walther H. Gas phase trapped ion studies of collisionally formed MgC60+ complexes. J Chem Phys 2002. [DOI: 10.1063/1.1478698] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
We introduce a novel way of performing independent component analysis using a constrained version of the expectation-maximization (EM) algorithm. The source distributions are modeled as D one-dimensional mixtures of gaussians. The observed data are modeled as linear mixtures of the sources with additive, isotropic noise. This generative model is fit to the data using constrained EM. The simpler "soft-switching" approach is introduced, which uses only one parameter to decide on the sub- or supergaussian nature of the sources. We explain how our approach relates to independent factor analysis.
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Affiliation(s)
- M Welling
- California Institute of Technology, Pasadena, CA 91125, USA
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Welling M, Schuessler H, Thompson R, Walther H. Ion/molecule reactions, mass spectrometry and optical spectroscopy in a linear ion trap. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0168-1176(97)00251-6] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Welling M, Feitsma HI, Calame W, Pauwels EK. Localization of a bacterial infection with 99Tcm-labelled human IgG: further improvement with enriched IgG subclass preparations. Nucl Med Commun 1997; 18:1057-64. [PMID: 9423206 DOI: 10.1097/00006231-199711000-00009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The aim of this study was to determine the contribution of various IgG subclasses to the scintigraphic detection of a staphylococcal infection. An experimental thigh infection in mice was used to determine the accumulation of the various 99Tcm-labelled IgG preparations with enriched IgG1, IgG2 or IgG4 subclass. Multiple-regression analysis was used to investigate a relationship between the IgG subclasses and the time-dependent accumulation in infected sites. Eighteen hours after infection with Staphylococcus aureus bacteria 20 micrograms of 99Tcm-labelled IgG preparations enriched with one of the IgG1, IgG2 or IgG4 subclasses by thiophilic absorption were administered intravenously and target-to-nontarget (T/NT) ratios were determined at 15 min, 1 h, 4 h and 24 h after injection of the tracer. Moreover, the binding of these preparations to S. aureus was assessed using an in vitro bacterial pellet model as an indication for the potency of detecting infections. As a control agent, 99Tcm-labelled polyclonal IgG (HIG) was used. In vivo, the T/NT ratios were significantly (P < 0.05) higher for the IgG1-enriched preparation at all time points, and for the IgG2-enriched preparation at 4 h and 24 h after injection, compared with HIG. In contrast, IgG4 did not yield higher T/NT ratios at any time. Using multiple-regression analysis, it became evident that IgG3 at all time intervals, IgG1 for early scans (up to 4 h) and IgG2 for late scans (24 h) contribute significantly (P < 0.05) to the accumulation. The abundance of IgG subclasses in the various preparations appeared to influence the accumulation of tracer at infected sites. The percentage of binding to S. aureus in vitro was significantly (P < 0.05) higher for enriched IgG subclass preparations than for HIG. We conclude that specific subclass enrichment of 99Tcm-labelled IgG preparations improves the scintigraphic detection of staphylococcal infections at various time intervals post-injection.
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Affiliation(s)
- M Welling
- Department of Diagnostic Radiology and Nuclear Medicine, Leiden University Medical Centre, The Netherlands
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Welling M, Feitsma HI, Calame W, Pauwels EK. Detection of experimental infections with 99mTc-labeled monoclonal antibodies against TNF-alpha and interleukin-8. Nucl Med Biol 1997; 24:649-55. [PMID: 9352536 DOI: 10.1016/s0969-8051(97)00118-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study was designed to assess monoclonal antibodies (MAbs) directed against tumor necrosis factor-alpha (TNF-alpha) (anti-TNF) or interleukin-8 (anti-IL-8) as radioactive agents for the detection of Staphylococcus aureus-or Klebsiella pneumoniae-infected thighs in mice. At 5 min (acute infection) or 20 h (established) post-infection, 20 micrograms of the 99mTc-labeled MAbs were injected. At various time intervals, the accumulation of the radiotracer in the infected thighs was assessed and expressed as a target-to-nontarget (T/NT) ratio. The binding of 99mTc-labeled MAbs to circulating mononuclear cells and granulocytes was quantitated 20 h after injection. The pharmacokinetics of the MAbs, in relation to the control agents 99mTc-labeled polyclonal human immunoglobulin (IgG) and a 99mTc-labeled nonspecific IgG1 MAb, were also studied. In acute infections, 99mTc-anti-TNF accumulated to a higher extent (p < 0.05) in S. aureus-infected thighs in mice until 4 h after the injection than 99mTc-IgG and was higher at 0.25 h in K. pneumoniae-infected mice (p < 0.03) compared with 99mTc-IgG. In established S. aureus and K. pneumoniae infections, 99mTc-anti-IL-8 detected the infection more intensely than 99mTc-IgG until 1 h after injection. In both S. aureus and K. pneumoniae infections, localization of sites of infection correlates (p < 0.05) with increased binding of the 99mTc-labeled MAbs to granulocytes and mononuclear cells in both acute and established infections. It was concluded that 99mTc-labeled MAbs, directed against TNF-alpha and IL-8, accumulate in bacterial infections in mice to a higher extent than does 99mTc-IgG after infection and is related to the binding of the antibodies to blood leukocytes. With these 99mTc-labeled MAbs, information might be gained about the development of an infection.
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Affiliation(s)
- M Welling
- Department of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden, The Netherlands
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Fischer H, Waibel AE, Welling M, Wienhold FG, Zenker T, Crutzen PJ, Arnold F, Bürger V, Schneider J, Bregman A, Lelieveld J, Siegmund PC. Observations of high concentrations of total reactive nitrogen (NOy) and nitric acid (HNO3) in the lower Arctic stratosphere during the Stratosphere-Troposphere Experiment by Aircraft Measurements (STREAM) II campaign in February 1995. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jd02012] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Koppmann R, Khedim A, Rudolph J, Poppe D, Andreae MO, Helas G, Welling M, Zenker T. Emissions of organic trace gases from savanna fires in southern Africa during the 1992 Southern African Fire Atmosphere Research Initiative and their impact on the formation of tropospheric ozone. ACTA ACUST UNITED AC 1997. [DOI: 10.1029/97jd00845] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Andreae MO, Atlas E, Harris GW, Helas G, de Kock A, Koppmann R, Maenhaut W, Manø S, Pollock WH, Rudolph J, Scharffe D, Schebeske G, Welling M. Methyl halide emissions from savanna fires in southern Africa. ACTA ACUST UNITED AC 1996. [DOI: 10.1029/95jd01733] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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de Bois MH, Welling M, Verwey CL, de Vries E, Pauwels EK, Breedveld FC, Tak PP. 99Tcm-HIG accumulates in the synovial tissue of rats with adjuvant arthritis by binding to extracellular matrix proteins. Nucl Med Commun 1996; 17:54-9. [PMID: 8692474 DOI: 10.1097/00006231-199601000-00010] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Our objective was to investigate the mechanism of accumulation of 99Tcm-labelled non-specific polyclonal human immunoglobulin (99Tcm-HIG) in inflamed synovial tissue (ST) in an experimental animal model of arthritis. Following 99Tcm-HIG scintigraphy, the in vivo localization of 99Tcm-HIG in the ST of knee joints of rats with adjuvant arthritis was studied using immunohistochemical techniques. In addition, the in vitro binding of 99Tcm-HIG to extracellular matrix proteins was analysed by means of immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). After 99Tcm-HIG scintigraphy, 99Tcm-HI was detected in the ST of rats with adjuvant arthritis. 99Tcm-HIG was diffusely distributed and not bound to cells. In vitro incubation of 99Tcm-HIG on the ST of rats with adjuvant arthritis revealed binding of 99Tcm-HIG to inflamed, but not to non-inflamed, ST. In addition, specific binding of 99Tcm-HIG to fibronectin, fibrin, collagen type I and III was demonstrated by ELISA. We conclude that the accumulation of 99Tcm-HIG in inflamed ST can be explained by the binding of 99Tcm-HIG to extracellular matrix proteins.
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Affiliation(s)
- M H de Bois
- Department of Rheumatology, University Hospital Leiden, The Netherlands
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Calame W, Welling M, Feitsma HI, Goedemans WT, Pauwels EK. Contribution of phagocytic cells and bacteria to the accumulation of technetium-99m labelled polyclonal human immunoglobulin at sites of inflammation. Eur J Nucl Med 1995; 22:638-44. [PMID: 7498225 DOI: 10.1007/bf01254565] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The purpose of this study was to assess the contribution of phagocytic cells and bacteria to the accumulation of technetium-99m labelled polyclonal human immunoglobulin (HIG) at sites of inflammation. Mice were intraperitoneally injected with Staphylococcus aureus (SA animals), with heat-inactivated newborn calf serum (NBCS, to mimic a non-bacterial inflammation) or with physiological saline (controls); 1 h thereafter they received HIG. At various intervals after the administration of HIG the mice were killed, and the percentages of radioactivity in the peritoneal effluent and attached to the cellular and bacterial fraction thereof were established. Furthermore, the total number of cells and that of bacteria in the fluid were quantitated. The percentage of activity in the effluent in the SA animals was (P < 0.02) higher than those in the NBCS-injected animals and controls from 4 h onwards. In all groups of mice this percentage was highest at 4 h and decreased (P < 0.01) afterwards. The percentage of cell-bound activity and the total number of cells remained fairly constant or increased with time in the SA animals (P < 0.01). The bacteria-bound activity remained rather constant throughout the experiment and ranged between 4% and 6%. In the SA-infected animals the percentage of cell-bound activity was correlated with the total number of cells (macrophages but especially neutrophils) but even more strongly with the number of cell-associated bacteria. In the NBCS-injected animals a correlation was demonstrated between the cell-bound activity and the total number of cells (only neutrophils).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- W Calame
- Department of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden, The Netherlands
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Welling M, Feitsma HI, Blok D, Calame W, Ensing GJ, Goedemans W, Pauwels EK. A new 99mTc labelling method for leucocytes: in vitro and in vivo comparison with 99mTc-HMPAO. Q J Nucl Med 1995; 39:89-98. [PMID: 8574810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A new method for the labelling of mixed leucocytes with 99mTc-tropolone was optimized and compared with a 99mTc-HMPAO leucocyte labelling procedure in vitro and in vivo. In the present study, leucocytes obtained from patients suffering from Crohn's disease, were isolated and labelled with 99mTc-HMPAO or labelled according the new 99mTc-tropolone procedure using 9.8 mM tropolone, 1 microM stannous chloride and 0.8 mM potassium borohydride (KBH4) at pH 5.5-6. Labelling efficiency with 99mTc-tropolone yielded 92 +/- 3%, which is higher compared to the 99mTc-HMPAO labelling procedure (64 +/- 13%) using 10(8) of leucocytes. In vitro stability and viability of both the tropolone and the HMPAO labelled cells was investigated. The viability test of the 99mTc-labelled leucocytes was performed in autologous plasma at 37 degrees C and compared with unlabelled leucocytes. After 18 hours of incubation a significant (P < 0.05) higher stability was observed for 99mTc-tropolone labelled leucocytes (84 +/- 5%) compared with that of 99mTc-HMPAO labelled leucocytes (73 +/- 5%). The viability of the 99mTc-labelled leucocytes observed for both labelling procedures was similar to unlabelled leucocytes. In vivo experiments were performed in mice. 99mTc-tropolone or 99mTc-HMPAO labelled murine mixed leucocytes were injected in mice, with a Staphylococcus aureus ATCC 25923 thigh infection. Analysis of scintigraphic images yielded a faster clearance of the 99mTc-tropolone labelled leucocytes. This was most likely due to a significant (P < 0.02) higher liver uptake at 4 hours after administration of the 99mTc-tropolone labelled leucocytes (19%) in comparison with 99mTc-HMPAO labelled cells (9%). Faster and significant (P < 0.02) higher accumulation of the 99mTc-tropolone labelled leucocytes was observed at the site of infection compared with 99mTc-HMPAO labelled leucocytes at all time-intervals after the administration of the 99mTc-labelled leucocytes. The new 99mTc-tropolone leucocyte labelling procedure, offers an attractive low-cost agent for research purposes.
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Affiliation(s)
- M Welling
- Department of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden, The Netherlands
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Welling M, Feitsma HI, Calame W, Ensing GJ, Goedemans W, Pauwels EK. Optimized localization of bacterial infections with technetium-99m labelled human immunoglobulin after protein charge selection. Eur J Nucl Med 1994; 21:1135-40. [PMID: 7828624 DOI: 10.1007/bf00181070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To improve the scintigraphic detection of bacterial infections a protein charge-purified fraction of polyclonal human immunoglobulin was applied as a radiopharmaceutical. This purification was achieved by attaching the immunoglobulin to an anion-exchanger column and by obtaining the column-bound fraction with buffer. The binding to bacteria in vitro and the target to non-target ratios of an experimental thigh infection with Staphylococcus aureus or Klebsiella pneumoniae in mice were evaluated to compare the purified and the unpurified immunoglobulin. The percentage of binding to all gram-positive and gram-negative bacteria used in this study was significantly (P < 0.03) higher for the purified than for the unpurified immunoglobulin. For the in vivo study, mice were infected in the thigh muscle with Staph. aureus or K. pneumoniae. After 18 h 0.1 mg of technetium-99m labelled polyclonal immunoglobulin or 99mTc-labelled protein charge-purified polyclonal human immunoglobulin was administered intravenously. At all time intervals the target (infected thighs) to non-target (non-infected thighs) ratios for both infections were significantly higher (P < 0.03) for protein charge-purified polyclonal immunoglobulin than for unpurified polyclonal human immunoglobulin. Already within 1 h the infected tissues could be detected by the purified immunoglobulin. It is concluded that 99mTc-labelled protein charge-purified immunoglobulin localizes both a gram-positive and a gram-negative thigh infection more intensely and faster than 99mTc-labelled unpurified immunoglobulin.
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Affiliation(s)
- M Welling
- Department of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden, The Netherlands
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Calame W, Welling M, Feitsma HI, Ensing GJ, Pauwels EK. Improved detection of a staphylococcal infection by monomeric and protein A-purified polyclonal human immunoglobulin. Eur J Nucl Med 1993; 20:490-4. [PMID: 8339732 DOI: 10.1007/bf00175161] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The present study was undertaken to compare the technetium-99m labelled non-specific polyclonal human immunoglobulin (Ig) with 99mTc-labelled monomeric human immunoglobulin (m-Ig), 99mTc-labelled, protein A-purified, human immunoglobulin (A-Ig) and 99mTc-labelled monomeric, protein A-purified, human immunoglobulin (mA-Ig) as tracer agents for the detection of a thigh infection with Staphylococcus aureus. In vitro the binding of the various tracer agents to bacteria at various intervals was determined. For the in vivo evaluation, mice were infected and received one of the various labelled proteins. Scintigrams were made 0.25, 1, 4 and 24 h later. All 99mTc-labelled Igs bound to bacteria in vitro: the percentages of binding for the m-Ig (from 1 h onwards) and A-Ig and mA-Ig (from 3 h onwards) were significantly higher than that for Ig. The in vivo target-to-non-target (T/NT) ratios were significantly higher from 4 h onwards for all purified Igs than for Ig. Protein A-purified Igs yielded higher T/NT ratios than m-Ig. Furthermore, the amount of activity in the liver was significantly lower 24 h after administration of m-Ig, A-Ig and mA-Ig than after administration of Ig. It is concluded that in this experimental infection 99mTc-labelled monomeric Ig localizes a staphylococcal thigh infection better and faster than 99mTc-labelled unpurified Ig. However, the accumulation obtained with protein A-purified Ig or protein A-purified monomeric Ig was the highest of all tracer agents tested.
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Affiliation(s)
- W Calame
- Department of Diagnostic Radiology and Nuclear Medicine, University Hospital, Leiden, The Netherlands
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Wasser MN, Welling M, Lamers G, Pauwels EK, Nieuwenhuizen W. Effects of an antifibrin monoclonal antibody and fragments thereof on some properties of fibrin. Thromb Haemost 1990; 63:39-43. [PMID: 2111047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Antifibrin monoclonal antibody Y22, of IgG1-subclass, has its epitope in the D-domain of fibrin. In a thrombin time assay, Y22 and its F(ab)2 fragments interfere with clotting of citrated plasma. Transmission and scanning electronmicroscopic studies show that clotting of citrated blood or plasma in the presence of Y22 results in formation of thin, short fibrin fibres. The (smaller) Fab fragments of Y22 did not have an anti-clotting effect. This suggests that the anticoagulant effect of Y22 is due to steric hindrance of the association of fibrin monomers. A control antibody and its F(ab)2 and Fab fragments have no effect on fibrin formation. In a parabolic rate assay, Y22 Fab fragments interfered strongly with the fibrin-induced enhancement of the t-PA-catalyzed plasminogen activation, whereas intact Y22 and a control antibody did not. In contrast with their effects on the fibrin assembly, the effects of Y22, Y22-F(ab)2 and Y22-Fab on the capacity of fibrin to act as a rate-enhancer in the plasminogen activation by t-PA appears to decrease with the size of the immunoreactive entity. As is discussed, this may be due to the differential accessibility of sites involved in stimulation and polymerization which are located in the fibrin D-domain.
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Affiliation(s)
- M N Wasser
- Gaubius Institute TNO, Leiden, The Netherlands
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Van Der Laken CJ, Hagenaars AM, Hermsen G, Kriek E, Kuipers AJ, Nagel J, Scherer E, Welling M. Measurement of O6-ethyldeoxyguanosine and N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene in DNA by high-sensitive enzyme immunoassays. Carcinogenesis 1982; 3:569-72. [PMID: 7094214 DOI: 10.1093/carcin/3.5.569] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Antibodies raised in rabbits against the bovine serum albumin conjugates of O6-ethylguanosine and N-(guanosin-8-yl)-N-acetyl-2-aminofluorene have been used to develop a high-sensitive enzyme-linked immunosorbent assay (HS-ELISA) for the quantification of adducts in DNA modified by ethylating agents and N-acetyl-2-aminofluorene. Linear dose-response relations were obtained in the non-competitive HS-ELISA between 0.5 fmol and 50 fmol O6-ethyldeoxy-guanosine per 2.8 microgram DNA, and between 0.1 fmol and 20 fmol N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene per 0.8 microgram DNA. The sensitivity of an ultrasensitive radioimmunoassay was in the same order of magnitude. Modification levels as low as 0.1 mumol of adduct/mol DNA-nucleotides (1: 10(7)) can be detected by each assay.
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Featherman RE, Welling M. Using volunteers in a community mental health center. Hosp Community Psychiatry 1971; 22:113-4. [PMID: 5162565 DOI: 10.1176/ps.22.4.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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