91 results on '"Van Ostade X"'
Search Results
2. Tumor Necrosis Factor: Mechanism of Action and its Potential for Anticancer Therapy
- Author
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Fiers, W., Beyaert, R., Brouckaert, P., Decoster, E., De Valck, D., Everaerdt, B., Grooten, J., Lenaerts, A., Libert, C., Schulze-Osthoff, K., Takahashi, N., Van Bladel, S., Van Dorpe, C., Vanhaesebroeck, B., Van Ostade, X., Van Roy, F., Shugar, David, editor, Rode, Wojciech, editor, and Borowski, Edward, editor
- Published
- 1992
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3. Hair or salivary cortisol analysis to identify chronic stress in piglets?
- Author
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Prims, S., Vanden Hole, C., Van Cruchten, S., Van Ginneken, C., Van Ostade, X., and Casteleyn, C.
- Published
- 2019
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- View/download PDF
4. MAPPIT: a cytokine receptor-based two-hybrid method in mammalian cells
- Author
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Tavernier, J., Eyckerman, S., Lemmens, I., Van der Heyden, J., Vandekerckhove, J., and Van Ostade, X.
- Published
- 2002
5. Molecular epidemiology of human papillomaviruses from cervical samples in Ethiopia: A systematic review
- Author
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Habteyohannes, A.D., primary, Mekonnen, D., additional, Yismaw, G., additional, Biadgelegne, F., additional, Van Ostade, X., additional, and Abebe, T., additional
- Published
- 2019
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6. Tumour Necrosis Factor and Interleukin-6: Structure and Mechanism of Action of the Molecular, Cellular and in Vivo Level
- Author
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Fiers, W., Beyaert, R., Brouckaert, P., Everaerdt, B., Grooten, J., Haegeman, G., Libert, C., Suffys, P., Takahashi, N., Tavernier, J., Van Bladel, S., Vanhaesebroeck, B., Van Ostade, X., Van Roy, F., Lother, Heinz, editor, Dernick, Rudolf, editor, and Ostertag, Wolfram, editor
- Published
- 1989
- Full Text
- View/download PDF
7. Tumor Necrosis Factor: Mechanism of Action at the Molecular, Cellular and in vivo Level
- Author
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Fiers, W., primary, Beyaert, R., additional, Brouckaert, P., additional, Decoster, E., additional, De Valck, D., additional, Everaerdt, B., additional, Grooten, J., additional, Lenaerts, A., additional, Libert, C., additional, Schulze-Osthoff, K., additional, Takahashi, N., additional, Tavernier, J., additional, Van Bladel, S., additional, Van Dorpe, C., additional, Vanhaesebroeck, B., additional, Van Ostade, X., additional, and Van Roy, F., additional
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8. In vitro and in vivo Action of Tumor Necrosis Factor1
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Fiers, W., primary, Beyaert, R., additional, Brouckaert, P., additional, Everaerdt, B., additional, Haegeman, G., additional, Libert, C., additional, Suffys, P., additional, Takahashi, N., additional, Tavernier, J., additional, Van Bladel, S., additional, Vanhaesebroeck, B., additional, Van Ostade, X., additional, and Van Roy, F., additional
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9. Two Pathways of Tumor Necrosis Factor Signal Transduction: In vitro and in vivo Implications
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Fiers, W., primary, Beyaert, R., additional, Brouckaert, P., additional, Cauwels, A., additional, Declercq, W., additional, De Valck, D., additional, Everaerdt, B., additional, Goossens, V., additional, Grooten, J., additional, Haegeman, G., additional, Libert, C., additional, Schulze-Osthoff, K., additional, Takahashi, N., additional, Vandenabeele, P., additional, Vanhaesebroeck, B., additional, Van Ostade, X., additional, and Van Roy, F., additional
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10. Supplementing formula-fed piglets with a low molecular weight fraction of bovine colostrum whey results in an improved intestinal barrier1,2
- Author
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De Vos, M., primary, Huygelen, V., additional, Van Raemdonck, G., additional, Willemen, S., additional, Fransen, E., additional, Van Ostade, X., additional, Casteleyn, C., additional, Van Cruchten, S., additional, and Van Ginneken, C., additional
- Published
- 2014
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11. Interleukin 5 regulates the isoform expression of its own receptor alpha-subunit
- Author
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Tavernier J, Van der Heyden J, Verhee A, Guy Brusselle, Van Ostade X, Vandekerckhove J, North J, Sm, Rankin, Ab, Kay, and Ds, Robinson
- Subjects
Protein Conformation ,Recombinant Fusion Proteins ,Granulocyte-Macrophage Colony-Stimulating Factor ,Cell Differentiation ,Receptors, Interleukin ,Fetal Blood ,Hematopoietic Stem Cells ,Receptors, Interleukin-5 ,Eosinophils ,Gene Expression Regulation ,COS Cells ,Chlorocebus aethiops ,Animals ,Humans ,Protein Isoforms ,Interleukin-3 ,RNA, Messenger ,Interleukin-5 ,Cells, Cultured - Abstract
The receptor for interleukin 5 (IL-5) consists of a cytokine-specific alpha chain (IL-5Ralpha) and a signaling beta chain, which is shared with interleukin 3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF). These 3 cytokines can act in eosinophil development and activation in vitro, but gene deletion or antibody blocking of IL-5 largely ablates eosinophilic responses in models of allergic disease or helminth infection. We investigated factors acting in differential IL-5Ralpha gene splicing to generate either the membrane-anchored isoform (TM-IL-5Ralpha) which associates with the common beta chain to allow IL-5 responsiveness, or a secreted, antagonist variant (SOL-IL-5Ralpha). In a murine myeloid cell line (FDC-P1), transfected with minigenes allowing expression of either IL-5Ralpha variant, IL-5 itself, but not IL-3 or GM-CSF, stimulated a reversible switch toward expression of TM-IL-5Ralpha. A switch from predominantly soluble isoform to TM-IL-5Ralpha messenger RNA (mRNA) expression was also seen during IL-5-driven eosinophil development from human umbilical cord blood-derived CD34(+) cells; this was accompanied by surface expression of IL-5Ralpha and acquisition of functional responses to IL-5. IL-3 and GM-CSF also supported eosinophil development and up-regulation of TM-IL-5Ralpha mRNA in this system, but this was preceded by expression of IL-5 mRNA and was inhibited by monoclonal antibody to IL-5. These data suggest IL-5-specific signaling, not shared by IL-3 and GM-CSF, leading to a switch toward up-regulation of functional IL-5Ralpha and, furthermore, that IL-3 and GM-CSF-driven eosinophil development is dependent on IL-5, providing an explanation for the selective requirement of IL-5 for expansion of the eosinophil lineage. (Blood. 2000;95:1600-1607)
- Published
- 2000
12. Crosstalk between viruses and PML nuclear bodies: a network-based approach
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Van Damme E and Van Ostade X
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viruses ,Intranuclear Inclusion Bodies ,Intranuclear Inclusion Body ,Computational biology ,Biology ,Models, Biological ,Inclusion bodies ,Virus ,Inclusion Bodies, Viral ,Viral Proteins ,Promyelocytic leukemia protein ,Leukemia, Promyelocytic, Acute ,Nucleic Acids ,medicine ,Humans ,Nuclear protein ,food and beverages ,medicine.disease ,Neoplasm Proteins ,Chemistry ,Leukemia ,Crosstalk (biology) ,Nucleic acid ,biology.protein ,Human medicine - Abstract
Due to the recent advances in instrumental and scientific methods, cell biology data are generated with increasing speed and quantity. One of these fast developing fields is the crosstalk between promyelocytic peukemia protein nuclear bodies (PML-NBs) and viruses. PML-NBs are dynamic nuclear protein aggregates which are targeted by entire viral particles, viral proteins or viral nucleic acids. Their possible anti-viral properties motivated researchers to investigate the interaction between PML-NBs and viruses in depth. Based on extensive literature data mining, we created a comprehensive PML-NB/virus crosstalk Cytoscape network, which groups not only the most common relations but also less well described findings. The network is easy to navigate and provides a biologically relevant overview which can help finding interesting case studies.
- Published
- 2011
13. P10-08. Intracellular detection of differential APOBEC3G, TRIM5a, and LEDGF/p75 expression in peripheral blood from HIV-1 infected subjects by flow cytometry
- Author
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Mous, K, primary, Jennes, W, additional, Kestens, L, additional, and Van Ostade, X, additional
- Published
- 2009
- Full Text
- View/download PDF
14. Dissociation of TNF-alpha cytotoxic and proinflammatory activities by p55 receptor- and p75 receptor-selective TNF-alpha mutants.
- Author
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Barbara, J.A., primary, Smith, W.B., additional, Gamble, J.R., additional, Van Ostade, X., additional, Vandenabeele, P., additional, Tavernier, J., additional, Fiers, W., additional, Vadas, M.A., additional, and Lopez, A.F., additional
- Published
- 1994
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15. X-ray structure of the (Ala-84→Val] mutant of human tumor necrosis factor
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Saludjian, P., primary, Prange, T., additional, Van Ostade, X., additional, Tavernier, J., additional, Fiers, W., additional, and Navaza, J., additional
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- 1993
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16. Tumor necrosis factor: Mechanisms of action and potential role in cancer treatment
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Fiers, W., primary, Beyaert, R., additional, Brouckaert, P., additional, Cauwels, A., additional, Declercq, W., additional, De Valck, D., additional, Everaerdt, B., additional, Goossens, V., additional, Grooten, J., additional, Libert, C., additional, Takahashi, N., additional, Vandenabeele, P., additional, Vanhaesebroeck, B., additional, Van Ostade, X., additional, Van Roy, F., additional, and Vercammen, D., additional
- Published
- 1993
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- View/download PDF
17. Expression of an exogenous tumor necrosis factor (TNF) gene in TNF-sensitive cell lines confers resistance to TNF-mediated cell lysis.
- Author
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Vanhaesebroeck, B, primary, Decoster, E, additional, Van Ostade, X, additional, Van Bladel, S, additional, Lenaerts, A, additional, Van Roy, F, additional, and Fiers, W, additional
- Published
- 1992
- Full Text
- View/download PDF
18. Localization of the active site of human tumour necrosis factor (hTNF) by mutational analysis.
- Author
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Van Ostade, X., primary, Tavernier, J., additional, Prangé, T., additional, and Fiers, W., additional
- Published
- 1991
- Full Text
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19. MAPPIT: a cytokine receptor-based two-hybrid method in mammalian cells1.
- Author
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Tavernier, J., Eyckerman, S., Lemmens, I., Van der Heyden, J., Vandekerckhove, J., and Van Ostade, X.
- Subjects
CYTOKINES ,CELL receptors ,CELLS - Abstract
Summary Identifying novel targets for therapy in allergic disease: protein interactions inside the cell Therapy of allergic disease currently relies on pharmacological manipulation of mediators or immunotherapy. Drugs have been developed to target specific mediators and their receptors: for example antihistamines blocking the H
1 receptor have been refined to maximize antagonism and reduce central side-effects or adverse effects of activity on other receptors such as muscarinic cholinergic receptors. Traditional pharmacological approaches identify new surface receptors against which chemists will then design or screen compounds for activity: examples are H3 or H4 histamine receptors. With the advent of the sequenced human genome we are faced with a vast array of genes and proteins that interact to define normal physiology or indeed pathology. A major challenge to biotechnology is to evolve novel techniques to understand the function and interaction of these myriad proteins. One particular area of current interest is the signalling cascades downstream of surface receptors. For many years pathways have appeared overlapping and to offer little chance of specific intervention. However, greater understanding of the complexity and integration of signalling, together with the possibility of directing drugs to specific cells has aroused considerable interest in this area for novel therapeutics. Indeed, targeting events within the cell has been done for many years with steroids. Here, Jan Tavernier and colleagues describe some signalling pathways relevant to allergic disease and potential methods for understanding protein interactions that allow mapping of the cascades. In particular they describe an elegant new system of analysis of protein–protein interactions in a mammalian system, which they have developed, termed MAPPIT. The basis of the system is an engineered receptor with JAK kinase but which lacks STAT activation sites.... [ABSTRACT FROM AUTHOR]- Published
- 2002
- Full Text
- View/download PDF
20. Dimerization of the interferon type I receptor IFNaR2-2 is sufficient for induction of interferon effector genes but not for full antiviral activity.
- Author
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Pattyn, E, Van Ostade, X, Schauvliege, L, Verhee, A, Kalai, M, Vandekerckhove, J, and Tavernier, J
- Abstract
We constructed chimeric receptors wherein the extracellular domain of the erythropoietin receptor (EpoR) was fused to the transmembrane and intracellular domains of the interferon (IFN) type I receptor subunits, IFNaR1 or IFNaR2-2. Transfection into 2fTGH and Tyk2-deficient 11,1 cells showed that EpoR/IFNaR2-2 alone was able to transduce a signal upon stimulation with erythropoietin (Epo), as judged by induction of the interferon type I-inducible 6-16 promoter. In contrast, protection against infection with encephalomyocarditis virus or vesicular stomatitis virus was reduced or absent, respectively. To further investigate the role of IFNaR1 in the induction of an antiviral state, we analyzed the Epo- versus IFNalpha-induced transcription of a set of genes, involved in antiviral protection. Up to 24 h after stimulation with Epo or IFNalpha, comparable transcription of the p56, dsRNA-dependent protein kinase, 2'-5'A synthetase, and MxA genes was seen. However, at later time points, only in the case of Epo induction, a sharp decrease of mRNA levels was observed. Western blotting analysis of dsRNA-dependent protein kinase showed a similar pattern at the protein level. Taken together, our results imply a role for IFNaR1 in the induction of sustained mRNA and protein levels that are likely required for optimal antiviral activity.
- Published
- 1999
21. Regulation of neutrophil apoptosis by tumor necrosis factor-alpha: requirement for TNFR55 and TNFR75 for induction of apoptosis in vitro
- Author
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Murray J, Ja, Barbara, Sa, Dunkley, Af, Lopez, Van Ostade X, Am, Condliffe, Dransfield I, Haslett C, and Edwin Chilvers
- Subjects
Lipopolysaccharides ,Phytic Acid ,Neutrophils ,Tumor Necrosis Factor-alpha ,Antibodies, Monoclonal ,Granulocyte-Macrophage Colony-Stimulating Factor ,Apoptosis ,DNA Fragmentation ,Leukotriene B4 ,Receptors, Tumor Necrosis Factor ,Recombinant Proteins ,N-Formylmethionine Leucyl-Phenylalanine ,Kinetics ,Antigens, CD ,Receptors, Tumor Necrosis Factor, Type I ,Humans ,Receptors, Tumor Necrosis Factor, Type II ,Platelet Activating Factor ,Cells, Cultured ,Signal Transduction - Abstract
Granulocyte apoptosis is an important mechanism underlying the removal of redundant neutrophils from an inflammatory focus. The ability of many proinflammatory agents to impede this event suggests that such agents act not only in a priming or secretagogue capacity but also increase neutrophil longevity by delaying apoptosis. We have examined whether this hypothesis holds true for all neutrophil priming agents, in particular tumor necrosis factor-alpha (TNF-alpha), which has been variably reported to either induce, delay, or have no effect on neutrophil apoptosis. After 20 hours coincubation TNF-alpha inhibited neutrophil apoptosis; however, more detailed analysis demonstrated its ability to promote apoptosis in a subpopulation of cells at earlier (2 to 8 hours) times. Formyl-Met-Leu-Phe, platelet-activating factor, inositol hexakisphosphate, lipopolysaccharide, leukotriene B4, and granulocyte-macrophage colony-stimulating factor all inhibited apoptosis at 6 and 20 hours. The early proapoptotic effect of TNF-alpha was concentration-dependent (EC50 2.8 ng/mL), abolished by TNF-alpha neutralizing antibody, and was not associated with any change in cell viability or recovery. Of relevance to the inflamed site, the ability of TNF-alpha to accelerate apoptosis was lost if neutrophils were primed with 1 micromol/L PAF or aged for 6 hours before TNF-alpha addition. The TNFR55-selective TNF-alpha mutants (E146K, R32W-S86T) induced neutrophil apoptosis but with a potency 14-fold lower than wild-type TNF-alpha. Although the TNFR75-selective mutant (D143F) did not induce apoptosis, blocking antibodies to both receptor subtypes abolished TNF-alpha-stimulated apoptosis. Hence, TNF-alpha has the unique ability to induce apoptosis in human neutrophils via a mechanism where TNFR75 facilitates the dominant TNFR55 death effect. This may be an important mechanism controlling neutrophil longevity and clearance in vivo.
22. Use of cervicovaginal fluid for the identification of biomarkers for pathologies of the female genital tract
- Author
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Tjalma Wiebren AA, Van Raemdonck Geert AA, Zegels Geert, and Van Ostade Xaveer WM
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Cytology ,QH573-671 - Abstract
Abstract Cervicovaginal fluid has an important function in the homeostasis and immunity of the lower female genital tract. Analysis of the cervicovaginal fluid proteome may therefore yield important information about the pathogenesis of numerous gynecological pathologies. Additionally, cervicovaginal fluid has great potential as a source of biomarkers for these conditions. This review provides a detailed discussion about the human cervicovaginal proteome and the proteomics studies performed to characterize this biological fluid. Furthermore, infection-correlated pathological conditions of the female genital tract are discussed for which cervicovaginal fluid has been used in order to identify potential biomarkers. Recent years, numerous studies have analyzed cervicovaginal fluid samples utilizing antibody-based technologies, such as ELISA or Western blotting, to identify biomarkers for preterm birth, premature preterm rupture of membranes, bacterial vaginosis and cervical cancer. The present article will discuss the importance of proteomic technologies as alternative techniques to gain additional meaningful information about these conditions. In addition, the review focuses on recent proteomic studies on cervicovaginal fluid samples for the identification of potential biomarkers. We conclude that the use of proteomic technology for analysis of human cervicovaginal fluid samples is promising and may lead to the discovery of new biomarkers which can improve disease prevention and therapy development.
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- 2010
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23. Comprehensive proteomic analysis of human cervical-vaginal fluid using colposcopy samples
- Author
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Tjalma Wiebren AA, Coen Edmond P, Van Raemdonck Geert AA, Zegels Geert, and Van Ostade Xaveer WM
- Subjects
Cytology ,QH573-671 - Abstract
Abstract Background Cervical-vaginal fluid (CVF) plays an important role in the prevention of gynecological infections, although little is known about the contribution of CVF proteins to the immunity of the lower female genital tract. In order to analyze the protein composition of human CVF, we used CVF samples that are routinely collected during colposcopy, but are usually discarded. Since these samples are available in large quantities we aimed to analyze their usefulness for proteomics experiments. The samples were analyzed using different prefractionation techniques (ultrafiltration and C4(RP)-LC protein separation) followed by C18(RP)-LC peptide separation and identification by MALDI-TOF-TOF mass spectrometry. To determine the reproducibility of this proteomics platform we analyzed three technical replicates. Using spectral counting, protein abundances were estimated in a semiquantitative way. We also compared the results obtained in this study with those from previous studies derived from patients with different physiological conditions in order to determine an overlapping protein set. Results In total, we were able to identify 339 proteins in human CVF of which 151 proteins were not identified in any other proteomics study on human CVF so far. Those included antimicrobial peptides, such as human beta-defensin 2 and cathelicidin, which were known to be present in CVF, and endometrial proteins such as glycodelin and ribonucleoprotein A. Comparison of our results with previously published data led to the identification of a common protein set of 136 proteins. This overlapping protein set shows increased fractions of immunological and extracellular proteins, confirming the extracellular immunological role of CVF. Conclusion We demonstrated here that CVF colposcopy samples can be used in proteomics experiments and hence are applicable for biomarker discovery experiments. The delineation of an overlapping set of proteins that is identified in most proteomics studies on CVF may help in the description of a reference proteome when performing proteomics studies on human CVF.
- Published
- 2009
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24. MAPPIT: a cytokine receptor-based two-hybrid method in mammalian cells1.
- Author
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Tavernier, J., Eyckerman, S., Lemmens, I., Van der Heyden, J., Vandekerckhove, J., and Van Ostade, X.
- Subjects
- *
CYTOKINES , *CELL receptors , *CELLS - Abstract
Summary Identifying novel targets for therapy in allergic disease: protein interactions inside the cell Therapy of allergic disease currently relies on pharmacological manipulation of mediators or immunotherapy. Drugs have been developed to target specific mediators and their receptors: for example antihistamines blocking the H1 receptor have been refined to maximize antagonism and reduce central side-effects or adverse effects of activity on other receptors such as muscarinic cholinergic receptors. Traditional pharmacological approaches identify new surface receptors against which chemists will then design or screen compounds for activity: examples are H 3 or H 4 histamine receptors. With the advent of the sequenced human genome we are faced with a vast array of genes and proteins that interact to define normal physiology or indeed pathology. A major challenge to biotechnology is to evolve novel techniques to understand the function and interaction of these myriad proteins. One particular area of current interest is the signalling cascades downstream of surface receptors. For many years pathways have appeared overlapping and to offer little chance of specific intervention. However, greater understanding of the complexity and integration of signalling, together with the possibility of directing drugs to specific cells has aroused considerable interest in this area for novel therapeutics. Indeed, targeting events within the cell has been done for many years with steroids. Here, Jan Tavernier and colleagues describe some signalling pathways relevant to allergic disease and potential methods for understanding protein interactions that allow mapping of the cascades. In particular they describe an elegant new system of analysis of protein–protein interactions in a mammalian system, which they have developed, termed MAPPIT. The basis of the system is an engineered receptor with JAK kinase but which lacks STAT activation sites.... [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
25. Expression analysis of the cellular HIV-related host factors LEDGF/p75, APOBEC3G, TRIM5alpha and tetherin in frequently HIV-exposed seronegative individuals
- Author
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Mous, K., UA, ITM, Van Ostade, X., Kestens, L., and Jennes, W.
- Subjects
Seronegativity ,AIDS ,Virology ,Immunology ,HIV ,Viral diseases - Published
- 2012
26. Welfare Assessment in Pigs Using the Salivary Proteome.
- Author
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Prims S, Van Ginneken C, Van Ostade X, and Casteleyn C
- Abstract
Identifying the potential presence of stress at the pig farm is fundamental since it affects pig welfare. As a result, a reliable and straightforward tool to monitor stress could record the welfare status of the animals. Although numerous methods to assess the welfare of pigs have been developed in the past, no gold standard has been established yet. Recently, the value of saliva as a tool to identify chronic stress in piglets was explored, as it can be collected fast and non-invasively. Since the protein composition, i.e., the proteome of porcine saliva, responds to stress, the affected proteins could be used as salivary stress biomarkers. The present review first defines stress and its relationship with welfare. Next, the porcine gland-specific salivary proteome is characterized. Finally, six potential salivary biomarkers for stress are proposed, i.e., odorant-binding protein, vomeromodulin-like protein, chitinase, lipocalin-1, long palate lung and nasal epithelium protein, and alpha-2-HS-glycoprotein.
- Published
- 2024
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27. Chronic exposure to multiple stressors alters the salivary proteome of piglets.
- Author
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Prims S, Van Ostade X, Ayuso M, Dom M, Van Raemdonck G, Van Cruchten S, Casteleyn C, and Van Ginneken C
- Subjects
- Animals, Swine, Biomarkers metabolism, Saliva metabolism, Animal Welfare, Proteome metabolism, Salivary Proteins and Peptides metabolism
- Abstract
Monitoring chronic stress in pigs is not only essential in view of animal welfare but is also important for the farmer, given that stress influences the zootechnical performance of the pigs and increases their susceptibility to infectious diseases. To investigate the use of saliva as a non-invasive, objective chronic stress monitoring tool, twenty-four 4-day-old piglets were transferred to artificial brooders. At the age of 7 days, they were assigned to either the control or the stressed group and reared for three weeks. Piglets in the stressed group were exposed to overcrowding, absence of cage enrichment, and frequent mixing of animals between pens. Shotgun analysis using an isobaric labelling method (iTRAQ) for tandem mass spectrometry performed on saliva samples taken after three weeks of chronic stress identified 392 proteins, of which 20 proteins displayed significantly altered concentrations. From these 20 proteins, eight were selected for further validation using parallel reaction monitoring (PRM). For this validation, saliva samples that were taken one week after the start of the experiment and samples that were taken at the end of the experiment were analysed to verify the profile over time. We wanted to investigate whether the candidate biomarkers responded fast or rather slowly to the onset of chronic exposure to multiple stressors. Furthermore, this validation could indicate whether age influenced the baseline concentrations of these salivary proteins, both in healthy and stressed animals. This targeted PRM analysis confirmed that alpha-2-HS-glycoprotein was upregulated in the stressed group after one and three weeks, while odorant-binding protein, chitinase, long palate lung and nasal epithelium protein 5, lipocalin-1, and vomeromodulin-like protein were present in lower concentrations in the saliva of the stressed pigs, albeit only after three weeks. These results indicate that the porcine salivary proteome is altered by chronic exposure to multiple stressors. The affected proteins could be used as salivary biomarkers to identify welfare problems at the farm and facilitate research to optimise rearing conditions., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Prims et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2023
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28. Adverse Drug Reactions during COVID-19 Treatment: A Comprehensive Analysis Focused on Hospitalized Patients, with the Use of a Survey in Cuba in 2020.
- Author
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Gil-Del-Valle L, Gravier-Hernández R, Baldoquin-Rodríguez W, Sierra-Vázquez B, Perez-Díaz AB, Sariol-Resik P, Prieto-Dominguez T, Delgado-Guerra MM, Sánchez-Márquez JA, López-Fernández OE, Fonseca-Betancourt F, Valdés-Lanza L, Orraca-Castillo O, Van Ostade X, Vanden Berghe W, Vanlerberghe V, and Guzmán-Tirado MG
- Abstract
Aims: To evaluate the prevalence and type of adverse drug reactions (ADRs), together with associated risk factors, among Cuban COVID-19 patients treated with chloroquine (CQ), lopinavir/ritonavir (LPV/r), or interferon α 2b (IFN α 2b), according to the Cuban protocol., Materials and Methods: A prospective descriptive analysis of ADRs was performed on 200 COVID-19 patients who were admitted consecutively to three hospitals in Havana and Pinar del Río from April to July 2020. Information on demographics, ADRs, outcomes, behavioral, and health-related factors was collected using a validated questionnaire and clinical records. Each potential ADR case was assessed for causality based on the WHO-UMC algorithm, concomitant drug influences, and the presence of any drug-drug interactions (DDI)., Results: The total frequency of ADRs was 55%, with predominantly gastrointestinal disorders and general symptoms (23% vs 20%). 95.1% of ADRs occurred within 10 days after treatment and 42 potential DDI in 55.5% of patients (61/110) were observed. The prevalence of ADRs was: 44%, 30.4%, and 26.4% for IFN α 2b, LPV/r, and CQ, respectively. Sex (odds ratio (OR): 0.40 (95% confidence interval (CI): 0.211-0.742), age (OR: 2.36 (95% CI: 1.02-5.44)), and underlying diseases (OR: 0.12 (95% CI: 0.06-0.23)) were independently associated factors for ADRs ( P < 0.05)., Conclusions: The frequency of ADRs and potential DDI was high compared to their use during nonpandemic times (e.g., for malaria, HIV, or inflammatory diseases). The safety profile of these drugs when used for COVID-19 treatment showed similar characteristics. Comorbidities, age >37 years old, and female sex were associated with ADRs., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2023 Lizette Gil-del-Valle et al.)
- Published
- 2023
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29. Triage of human papillomavirus infected women by methylation analysis in first-void urine.
- Author
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Van Keer S, van Splunter AP, Pattyn J, De Smet A, Herzog SA, Van Ostade X, Tjalma WAA, Ieven M, Van Damme P, Steenbergen RDM, and Vorsters A
- Subjects
- Adult, Female, Humans, Middle Aged, Uterine Cervical Neoplasms pathology, Biomarkers, Tumor urine, Cervix Uteri metabolism, Cervix Uteri pathology, DNA Methylation, Papillomavirus Infections metabolism, Uterine Cervical Neoplasms diagnosis
- Abstract
Host cell DNA methylation analysis in urine provides promising triage markers for women diagnosed with a high-risk (HR) human papillomavirus (HPV) infection. In this study, we have investigated a panel of six host cell methylation markers (GHSR, SST, ZIC1, ASCL1, LHX8, ST6GALNAC5) in cervicovaginal secretions collected within the first part of the urine void (FVU) from a referral population. Cytology, histology, and HPV DNA genotyping results on paired FVU and cervical samples were available. Urinary median methylation levels from HR-HPV (n = 93) positive women were found to increase for all markers with severity of underlying disease. Significantly elevated levels were observed for GHSR and LHX8 in relation to high-grade cervical intraepithelial neoplasia (CIN2 +; n = 33), with area under de curve values of 0.80 (95% Confidence Interval (CI) 0.59-0.92) and 0.76 (95% CI 0.58-0.89), respectively. These findings are the first to support the assertion that methylation analysis of host cell genes is feasible in FVU and holds promise as molecular, triage strategy to discern low- from high-grade cervical disease in HR-HPV positive women. Molecular testing on FVU may serve to increase cervical cancer screening attendance in hard-to-reach populations whilst reducing loss to follow-up and await further optimization and validation studies.
- Published
- 2021
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30. Covalent Cysteine Targeting of Bruton's Tyrosine Kinase (BTK) Family by Withaferin-A Reduces Survival of Glucocorticoid-Resistant Multiple Myeloma MM1 Cells.
- Author
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Logie E, Chirumamilla CS, Perez-Novo C, Shaw P, Declerck K, Palagani A, Rangarajan S, Cuypers B, De Neuter N, Mobashar Hussain Urf Turabe F, Kumar Verma N, Bogaerts A, Laukens K, Offner F, Van Vlierberghe P, Van Ostade X, and Berghe WV
- Abstract
Multiple myeloma (MM) is a hematological malignancy characterized by plasma cells' uncontrolled growth. The major barrier in treating MM is the occurrence of primary and acquired therapy resistance to anticancer drugs . Often, this therapy resistance is associated with constitutive hyperactivation of tyrosine kinase signaling. Novel covalent kinase inhibitors, such as the clinically approved BTK inhibitor ibrutinib (IBR) and the preclinical phytochemical withaferin A (WA), have, therefore, gained pharmaceutical interest. Remarkably, WA is more effective than IBR in killing BTK-overexpressing glucocorticoid (GC)-resistant MM1R cells. To further characterize the kinase inhibitor profiles of WA and IBR in GC-resistant MM cells, we applied phosphopeptidome- and transcriptome-specific tyrosine kinome profiling. In contrast to IBR, WA was found to reverse BTK overexpression in GC-resistant MM1R cells. Furthermore, WA-induced cell death involves covalent cysteine targeting of Hinge-6 domain type tyrosine kinases of the kinase cysteinome classification, including inhibition of the hyperactivated BTK. Covalent interaction between WA and BTK could further be confirmed by biotin-based affinity purification and confocal microscopy. Similarly, molecular modeling suggests WA preferably targets conserved cysteines in the Hinge-6 region of the kinase cysteinome classification, favoring inhibition of multiple B-cell receptors (BCR) family kinases. Altogether, we show that WA's promiscuous inhibition of multiple BTK family tyrosine kinases represents a highly effective strategy to overcome GC-therapy resistance in MM.
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- 2021
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31. The CD147 Protein Complex Is Involved in Entry of Chikungunya Virus and Related Alphaviruses in Human Cells.
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De Caluwé L, Coppens S, Vereecken K, Daled S, Dhaenens M, Van Ostade X, Deforce D, Ariën KK, and Bartholomeeusen K
- Abstract
Chikungunya virus (CHIKV) is an arbovirus with a global spread and significant public health impact. It is a positive stranded RNA alphavirus belonging to the Togaviridae family. However, many questions about the replication cycle of CHIKV remain unanswered. The entry process of CHIKV is not completely understood nor are the associated virus-receptor interactions fully identified. Here, we designed an affinity purification mass spectrometry coupled approach that allowed the identification of factors that facilitate entry of CHIKV in human cells. The identified entry factors were further validated using CRISPR/Cas9. In HEK293T cells we identified the CD147 protein complex as an entry factor for CHIKV. We further showed the involvement of the CD147 protein complex in the replication cycle of related alphaviruses. Interestingly, CD147 contains similar protein domains as the previously identified alphavirus entry factor MXRA8., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 De Caluwé, Coppens, Vereecken, Daled, Dhaenens, Van Ostade, Deforce, Ariën and Bartholomeeusen.)
- Published
- 2021
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32. Starch biosynthesis contributes to the maintenance of photosynthesis and leaf growth under drought stress in maize.
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AbdElgawad H, Avramova V, Baggerman G, Van Raemdonck G, Valkenborg D, Van Ostade X, Guisez Y, Prinsen E, Asard H, Van den Ende W, and Beemster GTS
- Subjects
- Amino Acids metabolism, Antioxidants metabolism, Cell Division, Dehydration, Gene Expression Regulation, Plant, Mutation, Photosynthesis physiology, Plant Leaves physiology, Plant Proteins genetics, Plant Stomata physiology, Starch biosynthesis, Zea mays cytology, Droughts, Plant Leaves growth & development, Plant Proteins metabolism, Starch metabolism, Zea mays physiology
- Abstract
To understand the growth response to drought, we performed a proteomics study in the leaf growth zone of maize (Zea mays L.) seedlings and functionally characterized the role of starch biosynthesis in the regulation of growth, photosynthesis and antioxidant capacity, using the shrunken-2 mutant (sh2), defective in ADP-glucose pyrophosphorylase. Drought altered the abundance of 284 proteins overrepresented for photosynthesis, amino acid, sugar and starch metabolism, and redox-regulation. Changes in protein levels correlated with enzyme activities (increased ATP synthase, cysteine synthase, starch synthase, RuBisCo, peroxiredoxin, glutaredoxin, thioredoxin and decreased triosephosphate isomerase, ferredoxin, cellulose synthase activities, respectively) and metabolite concentrations (increased ATP, cysteine, glycine, serine, starch, proline and decreased cellulose levels). The sh2 mutant showed a reduced increase of starch levels under drought conditions, leading to soluble sugar starvation at the end of the night and correlating with an inhibition of leaf growth rates. Increased RuBisCo activity and pigment concentrations observed in WT, in response to drought, were lacking in the mutant, which suffered more oxidative damage and recovered more slowly after re-watering. These results demonstrate that starch biosynthesis contributes to maintaining leaf growth under drought stress and facilitates enhanced carbon acquisition upon recovery., (© 2020 John Wiley & Sons Ltd.)
- Published
- 2020
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33. Experimental Evidence on the Nature of the Antigen in the Direct Agglutination Test for Visceral Leishmaniasis.
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Kühne V, Verstraete R, van Ostade X, and Büscher P
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- Antibodies, Monoclonal, Antibodies, Protozoan, Enzyme-Linked Immunosorbent Assay, Humans, Leishmania donovani, Leishmania infantum, Sensitivity and Specificity, Agglutination Tests methods, Antigens, Protozoan, Leishmaniasis, Visceral diagnosis
- Abstract
The direct agglutination test (DAT) for visceral leishmaniasis (VL) is the serodiagnostic test for VL that has the most robust sensitivity and specificity in the field across all endemic regions. It is based on trypsin-treated and formaldehyde-fixed whole promastigote cells from Leishmania donovani . The exact identity and nature of the epitopes on the DAT antigen that cause agglutination with VL patients' sera are currently unknown. In this study, we performed antigen-inhibition studies which revealed that lipophosphoglycan (LPG) and the DAT antigen share epitopes. Antibody inhibition with a monoclonal antibody directed against the phosphoglycan repeat epitope of LPG showed that this is not the epitope that reacts with human sera. Oxidation of carbohydrates by sodium metaperiodate did not alter the reactivity of human sera with the DAT antigen and LPG. This indicates that carbohydrates do not play a role in the reaction of the DAT antigen with antibodies in serum from VL patients, and that they also are not involved in the reaction of LPG with the same serum. We conclude that the noncarbohydrate moiety of LPG, that is, the core-anchor fragment, and potentially other noncarbohydrate epitopes on the surface of the DAT antigen are responsible for its agglutination with antibodies from VL patients. As LPG plays a role in the DAT reaction, this could facilitate the following: 1) incorporation of LPG, preferably the synthetic version of the core-anchor fragment, into an immunochromatographic test format that is more adapted as a point-of-care test (short incubation, little training, and equipment needed) than DAT and 2) enhancing the quality control for the production of the DAT antigen.
- Published
- 2020
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34. HPV E6/E7 mRNA test for the detection of high grade cervical intraepithelial neoplasia (CIN2+): a systematic review.
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Derbie A, Mekonnen D, Woldeamanuel Y, Van Ostade X, and Abebe T
- Abstract
Background: Genital infection with certain types of Human papillomavirus (HPV) is a major cause of cervical cancer globally. For early detection of premalignant dysplasia, evidences are coming out on the usefulness of HPV E6/E7 mRNA test as a potential tool compared with cytology and HPV DNA testing. Taking into account shortage of compiled data on this field, the aim of this systematic review was to describe the latest diagnostic performance of HPV E6/E7 mRNA testing to detect high grade cervical lesions (CIN2+) where by histology was taken as a gold standard., Methods: Articles published in English were systematically searched using key words from PubMed/Medline and SCOPUS. In addition, Google Scholar and the Google database were searched manually for grey literature. Two reviewers independently assessed study eligibility, risk of bias and extracted the data. We performed a descriptive presentation of the performance of E6/E7 mRNA test (in terms of sensitivity, specificity, negative and positive predictive values) for the detection of CIN2 + ., Results: Out of 231 applicable citations, we have included 29 articles that included a total of 23,576 study participants (age range, 15-84 years) who had different cervical pathologies. Among the participants who had cervical histology, the proportion of CIN2+ was between 10.6 and 90.6%. Using histology as a gold standard, 11 studies evaluated the PreTect HPV Proofer, 7 studies evaluated the APTIMA HPV assay (Gen-Probe) and 6 studies evaluated the Quantivirus® HPV assay. The diagnostic performance of these three most common mRNA testing tools to detect CIN2+ was; 1) PreTect Proofer; median sensitivity 83%, specificity 73%, PPV 70 and NPV 88.9%. 2) APTIMA assay; median sensitivity 91.4%, specificity 46.2%, PPV 34.3% and NPV 96.3%. 3) Quantivirus®: median sensitivity 86.1%, specificity 54.6%, PPV 54.3% and NPV was at 89.3%. Further, the area under the receiver operating characteristics (AU-ROC) curve varied between 63.8 and 90.9%., Conclusions: The reported diagnostic accuracy implies that HPV mRNA based tests possess diagnostic relevance to detect CIN2+ and could potentially be considered in areas where there is no histology facility. Further studies including its cost should be considered., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2020.)
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- 2020
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35. Broad-spectrum antitumor properties of Withaferin A: a proteomic perspective.
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Dom M, Vanden Berghe W, and Van Ostade X
- Abstract
The multifunctional antitumor properties of Withaferin A (WA), the manifold studied bioactive compound of the plant Withania somnifera , have been well established in many different in vitro and in vivo cancer models. This undoubtedly has led to a much better insight in the underlying mechanisms of WAs broad antitumor activity range, but also raises additional challenging questions on how all these antitumor properties could be explained on a molecular level. Therefore, a lot of effort was made to characterize the cellular WA target proteins, since these binding events will lead and initiate the observed downstream effects. Based on a proteomic perspective, this review provides novel insights in the molecular chain of events by which WA potentially exercises its antitumor activities. We illustrate that WA triggers multiple cellular stress pathways such as the NRF2-mediated oxidative stress response, the heat shock response and protein translation events and at the same time inhibits these cellular protection mechanisms, driving stressed cancer cells towards a fatal state of collapse. If cancer cells manage to restore homeostasis and survive, a stress-independent WA antitumor response comes into play. These include the known inhibition of cytoskeleton proteins, NFκB pathway inhibition and cell cycle inhibition, among others. This review therefore provides a comprehensive overview which integrates the numerous WA-protein binding partners to formulate a general WA antitumor mechanism., (This journal is © The Royal Society of Chemistry 2020.)
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- 2019
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36. First-void urine as a non-invasive liquid biopsy source to detect vaccine-induced human papillomavirus antibodies originating from cervicovaginal secretions.
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Van Keer S, Willhauck-Fleckenstein M, Pattyn J, Butt J, Tjalma WAA, Van Ostade X, Hens N, Van Damme P, Waterboer T, and Vorsters A
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- Antibodies, Viral blood, Case-Control Studies, Cervix Uteri virology, Female, Human papillomavirus 11 immunology, Human papillomavirus 16 immunology, Human papillomavirus 18 immunology, Humans, Immunoglobulin A blood, Immunoglobulin A urine, Immunoglobulin G blood, Immunoglobulin G urine, Liquid Biopsy, Papillomavirus Infections immunology, Papillomavirus Infections urine, Vaccination, Vagina virology, Young Adult, Antibodies, Viral urine, Bodily Secretions virology, Papillomaviridae immunology, Papillomavirus Infections prevention & control, Papillomavirus Vaccines immunology
- Abstract
Background: Monitoring HPV antibodies non-invasively would be a major advantage for large epidemiological studies and follow-up of vaccinees., Objectives: This study investigated the presence of HPV-specific antibody transudates from systemic circulation in first-void urine of (un)vaccinated subjects and the agreement with paired sera., Study Design: In this case-control study, 55 paired first-void urine and serum samples were included from 19- to 26-year-old women, unvaccinated (n = 19) or vaccinated (n = 36) with the bi- or quadrivalent HPV vaccine during adolescence (NCT02714114). Human IgA, total human IgG, and HPV6/11/16/18-Ig(M/G/A) were measured in paired samples., Results: Significant positive Spearman rank correlations (r
s ) were found in HPV-specific antibody levels between paired samples (HPV6: rs = 0.777; HPV11: rs = 0.757; HPV16: rs = 0.876; HPV18: rs = 0.636 (p < 0.001)). In both first-void urine and serum, significantly higher HPV6/11/16/18 antibody levels were observed in vaccinated compared with unvaccinated women (p ≤ 0.017)., Conclusions: The present study provides the first proof that vaccine-induced HPV antibodies are detectable in the first-void urine of young women. Moreover, significant positive correlations were observed between HPV6/11/16/18-antibodies in first-void urine and paired sera. Further optimization and validation are required to demonstrate its potential use in epidemiological studies and follow-up of HPV vaccination., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2019
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37. Human papillomavirus in Ethiopia.
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Derbie A, Mekonnen D, Yismaw G, Biadglegne F, Van Ostade X, and Abebe T
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Over 99% of cervical cancer cases are associated with genital infection by certain types of human papillomaviruses (HPVs). To outline optimal vaccination strategies and HPV based cervical cancer screening, synthesized data on the genotype distribution of HPV is fundamental that is otherwise missed in Ethiopia. The aim of this study is to compile the findings on HPV genotyping in Ethiopia. Published articles were systematically searched using comprehensive search strings from PubMed/Medline and SCOPUS. Further, Google Scholar and the Google databases were also searched manually for grey literature. The included studies in the review employed 859 women (age range 15-85 years) with different kinds of cervical abnormalities. A total of 534 HPV sequences were reported; the proportion of high risk HPVs was varied 80.4-100%. The top five identified genotypes were HPV 16 (45.3%; 95% CI 41.1-49.6%), HPV 52 (9.4%; 95% CI 7.2-12.1%), HPV 18 (8.2%; 95% CI 6.2-10.9%), HPV 58 (6.9%; 95% CI 5.1-9.4%) and HPV 45 (5.2%; 95% CI 3.7-7.5%). The combined prevalence of HPV 16/18 was at 53.6% (95% CI 49.3-57.8%). In this review, HPV 16 in particular, but also HPV 52 and 18, warrant exceptional consideration in vaccination and HPV based screening programs in Ethiopia. To the best of our knowledge, this study represents the first of its kind to establish the genotype distribution of HPV from different kinds of cervical lesions in Ethiopia although it was synthesized out of few studies. Hence, additional nationwide data are needed to strengthen our finding.
- Published
- 2019
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38. On the characterisation of the porcine gland-specific salivary proteome.
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Prims S, Van Raemdonck G, Vanden Hole C, Van Cruchten S, Van Ginneken C, Van Ostade X, and Casteleyn C
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- Animals, Isoproterenol pharmacology, Pilocarpine pharmacology, Swine, Parotid Gland metabolism, Proteome metabolism, Salivary Proteins and Peptides metabolism, Sublingual Gland metabolism
- Abstract
To expand the knowledge on the porcine salivary proteome, secretions from the three major salivary glands were collected from anaesthetised piglets. Pilocarpine and isoproterenol were simultaneously injected intraperitoneally to increase the volume and protein concentration of the saliva, respectively. The protein composition and relative protein-specific abundance of saliva secreted by the parotid gland and by the mandibular and monostomatic sublingual gland, were determined using iTRAQ. When combining two detection methods, MALDI-TOF/TOF MS and Q-Exactive orbitrap MS/MS, a total of 122 porcine salivary proteins and 6 mammalian salivary proteins with a predicted porcine homolog were identified. Only a quantitative and not a qualitative difference was observed between both ductal secretions. The 128 proteins were detected in both secretions, however, at different levels. Twenty-four proteins (20 porcine and 4 mammalian with a predicted porcine homolog) were predominantly secreted by the parotid gland, such as carbonic anhydrase VI and alpha-amylase. Twenty-nine proteins (all porcine) were predominantly secreted by the mandibular and sublingual glands, for example salivary lipocalin and submaxillary apomucin protein. Data are available via ProteomeXchange with identifier PXD008853. SIGNIFICANCE: In humans, more than 3000 salivary proteins have been identified. To our knowledge, previous studies on porcine saliva only identified a total of 34 proteins. This research increased the total number of identified proteins in porcine saliva to 143. This insight into the porcine salivary proteome will facilitate the search for potential biomarkers that may help in the early detection of pathologies and follow-up of animal welfare. Moreover, it can also endorse the value of a porcine animal model and contribute to a better understanding of the animal's physiology. Additionally, this was the first study to collect and analyse gland specific saliva of pigs. The obtained relative-quantitative knowledge of the identified proteins is valuable when comparing data of stimulated (chewing on a device) vs. unstimulated (passive) saliva collection in the future, since salivary stimulation changes the relative contribution of the major salivary glands to the whole saliva in the oral cavity. For example, carbonic anhydrase VI, which is present in higher concentrations in parotid saliva, has a higher concentration in stimulated whole saliva because of the larger contribution of the parotid gland after stimulation by chewing., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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39. Proteomic characterization of Withaferin A-targeted protein networks for the treatment of monoclonal myeloma gammopathies.
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Dom M, Offner F, Vanden Berghe W, and Van Ostade X
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- Cell Line, Tumor, Humans, Multiple Myeloma drug therapy, Multiple Myeloma metabolism, Multiple Myeloma pathology, Apoptosis drug effects, Gene Expression Regulation, Neoplastic drug effects, Neoplasm Proteins biosynthesis, Proteomics, Withanolides pharmacology
- Abstract
Withaferin A (WA), a natural steroid lactone from the plant Withania somnifera, is often studied because of its antitumor properties. Although many in vitro and in vivo studies have been performed, the identification of Withaferin A protein targets and its mechanism of antitumor action remain incomplete. We used quantitative chemoproteomics and differential protein expression analysis to characterize the WA antitumor effects on a multiple myeloma cell model. Identified relevant targets were further validated by Ingenuity Pathway Analysis and Western blot and indicate that WA targets protein networks that are specific for monoclonal gammopathy of undetermined significance (MGUS) and other closely related disorders, such as multiple myeloma (MM) and Waldenström macroglobulinemia (WM). By blocking the PSMB10 proteasome subunit, downregulation of ANXA4, potential association with HDAC6 and upregulation of HMOX1, WA puts a massive blockage on both proteotoxic and oxidative stress responses pathways, leaving cancer cells defenseless against WA induced stresses. These results indicate that WA mediated apoptosis is preceded by simultaneous targeting of cellular stress response pathways like proteasome degradation, autophagy and unfolded protein stress response and thus suggests that WA can be used as an effective treatment for MGUS and other closely related disorders., Significance: Multifunctional antitumor compounds are of great potential since they reduce the risk of multidrug resistance in chemotherapy. Unfortunately, characterization of all protein targets of a multifunctional compound is lacking. Therefore, we optimized an SILAC quantitative chemoproteomics workflow to identify the potential protein targets of Withaferin A (WA), a natural multifunctional compound with promising antitumor properties. To further understand the antitumor mechanisms of WA, we performed a differential protein expression analysis and combined the altered expression data with chemoproteome WA target data in the highly curated Ingenuity Pathway database. We provide a first global overview on how WA kills multiple myeloma cancer cells and serve as a starting point for further in depth experiments. Furthermore, the combined approach can be used for other types of cancer and/or other promising multifunctional compounds, thereby increasing the potential development of new antitumor therapies., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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40. Human papillomavirus genotype and viral load agreement between paired first-void urine and clinician-collected cervical samples.
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Van Keer S, Tjalma WAA, Pattyn J, Biesmans S, Pieters Z, Van Ostade X, Ieven M, Van Damme P, and Vorsters A
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- Adult, Alphapapillomavirus classification, Alphapapillomavirus isolation & purification, Cervix Uteri pathology, Colposcopy, DNA, Viral, Female, Humans, Liquid Biopsy, Middle Aged, Papillomavirus Infections complications, Papillomavirus Infections diagnosis, Real-Time Polymerase Chain Reaction, Reproducibility of Results, Uterine Cervical Neoplasms etiology, Uterine Cervical Neoplasms pathology, Alphapapillomavirus genetics, Cervix Uteri virology, Genotype, Papillomavirus Infections urine, Papillomavirus Infections virology, Viral Load
- Abstract
The performance and acceptability of first-void urine as specimen for the detection of HPV DNA in a Belgian referral population was evaluated using an optimized sample collection and processing protocol. One hundred ten first-void urine and cervical samples were collected from 25- to 64-year-old women who were referred for colposcopy (January-November 2016). Paired samples were analyzed by the Riatol qPCR HPV genotyping assay. Acceptability data were gathered through questionnaires (NCT02714127). A higher high-risk HPV DNA prevalence was observed in first-void urine (n = 76/110) compared to cervical samples (n = 73/110), with HPV31 and HPV16/31 being most prevalent correspondingly. For both any and high-risk HPV DNA, good agreement was observed between paired samples (Cohen's Kappa of 0.660 (95% CI: 0.486-0.833) and 0.688 (95% CI: 0.542-0.835), respectively). In addition, significant positive correlations in HPV copies (per microliter of DNA extract) between paired samples were observed for HPV16 (r
s = 0.670; FDR (false discovery rate)-adjusted p = 0.006), HPV18 (rs = 0.893; FDR-adjusted p = 0.031), HPV31 (rs = 0.527; FDR-adjusted p = 0.031), HPV53 (rs = 0.691; FDR-adjusted p = 0.017), and HPV68 (rs = 0.569; FDR-adjusted p = 0.031). First-void urine sampling using a first-void urine collection device was preferred over a clinician-collected cervical sample. And mostly, first-void urine sampling at home was favored over collection at the clinic or the general practitioner's office. First-void urine sampling is a highly preferred, non-invasive method that ensures good agreement in HPV DNA (copies) with reference cervical samples. It is particularly interesting as a screening technique to reach non-participants, and its clinical performance should be further evaluated.- Published
- 2018
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41. Needle lost in the haystack: multiple reaction monitoring fails to detect Treponema pallidum candidate protein biomarkers in plasma and urine samples from individuals with syphilis.
- Author
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Van Raemdonck GA, Osbak KK, Van Ostade X, and Kenyon CR
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- Adolescent, Adult, Aged, Aged, 80 and over, Animals, Humans, Male, Middle Aged, Proteome analysis, Rabbits, Syphilis blood, Syphilis microbiology, Syphilis urine, Young Adult, Bacterial Proteins blood, Bacterial Proteins urine, Biomarkers blood, Biomarkers urine, Mass Spectrometry methods, Syphilis diagnosis, Treponema pallidum isolation & purification
- Abstract
Background: Current syphilis diagnostic strategies are lacking a sensitive manner of directly detecting Treponema pallidum antigens. A diagnostic test that could directly detect T. pallidum antigens in individuals with syphilis would be of considerable clinical utility, especially for the diagnosis of reinfections and for post-treatment serological follow-up. Methods: In this study, 11 candidate T. pallidum biomarker proteins were chosen according to their physiochemical characteristics, T. pallidum specificity and predicted abundance. Thirty isotopically labelled proteotypic surrogate peptides (hPTPs) were synthesized and incorporated into a scheduled multiple reaction monitoring assay. Protein extracts from undepleted/unenriched plasma (N = 18) and urine (N = 4) samples from 18 individuals with syphilis in various clinical stages were tryptically digested, spiked with the hPTP mixture and analysed with a triple quadruple mass spectrometer. Results: No endogenous PTPs corresponding to the eleven candidate biomarkers were detected in any samples analysed. To estimate the Limit of Detection (LOD) of a comparably sensitive mass spectrometer (LTQ-Orbitrap), two dilution series of rabbit cultured purified T. pallidum were prepared in PBS. Polyclonal anti- T. pallidum antibodies coupled to magnetic Dynabeads were used to enrich one sample series; no LOD improvement was found compared to the unenriched series. The estimated LOD of MS instruments is 300 T. pallidum /ml in PBS. Conclusions: Biomarker protein detection likely failed due to the low (femtomoles/liter) predicted concentration of T. pallidum proteins. Alternative sample preparation strategies may improve the detectability of T. pallidum proteins in biofluids., Competing Interests: No competing interests were disclosed.
- Published
- 2018
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42. Candidate biomarkers in the cervical vaginal fluid for the (self-)diagnosis of cervical precancer.
- Author
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Van Ostade X, Dom M, Tjalma W, and Van Raemdonck G
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- Adult, DNA Methylation, Female, Humans, Mass Screening, Middle Aged, Papillomaviridae physiology, Papillomavirus Infections diagnosis, Precancerous Conditions metabolism, Uterine Cervical Dysplasia diagnosis, Uterine Cervical Neoplasms diagnosis, Uterine Cervical Neoplasms virology, Vaginal Smears, Biomarkers, Tumor metabolism, Body Fluids metabolism, Cervix Uteri metabolism, Neoplasm Proteins metabolism, Uterine Cervical Neoplasms metabolism, Vagina metabolism
- Abstract
Purpose: Despite improvement in vaccines against human papilloma virus (HPV), the causative agent of cervical cancer, screening women for cervical precancer will remain indispensable in the coming 30-40 years. A simple test that could be performed at home or at a doctor's practice and that informs the woman whether she is at risk would significantly help make a broader group of patients who aware that they need medical treatment. Cervical vaginal fluid (CVF) is a body fluid that is very well suited for such a test., Methods: Narrative review of cervical (pre)cancer candidate biomarkers from cervicovaginal fluid, is based on a detailed review of the literature. We will also discuss the possibilities that these biomarkers create for the development of a self-test or point-of-care test for cervical (pre)cancer., Results: Several DNA, DNA methylation, miRNA, and protein biomarkers were identified in the cervical vaginal fluid; however, not all of these biomarkers are suited for development of a simple diagnostic assay., Conclusions: Proteins, especially alpha-actinin-4, are most suited for development of a simple assay for cervical (pre)cancer. Accuracy of the test could further be improved by combination of several proteins or by combination with a new type of biomarker, e.g., originating from the cervicovaginal microbiome or metabolome.
- Published
- 2018
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43. Selective Glucocorticoid Receptor Properties of GSK866 Analogs with Cysteine Reactive Warheads.
- Author
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Chirumamilla CS, Palagani A, Kamaraj B, Declerck K, Verbeek MWC, Oksana R, De Bosscher K, Bougarne N, Ruttens B, Gevaert K, Houtman R, De Vos WH, Joossens J, Van Der Veken P, Augustyns K, Van Ostade X, Bogaerts A, De Winter H, and Vanden Berghe W
- Abstract
Synthetic glucocorticoids (GC) are the mainstay therapy for treatment of acute and chronic inflammatory disorders. Due to the high adverse effects associated with long-term use, GC pharmacology has focused since the nineties on more selective GC ligand-binding strategies, classified as selective glucocorticoid receptor (GR) agonists (SEGRAs) or selective glucocorticoid receptor modulators (SEGRMs). In the current study, GSK866 analogs with electrophilic covalent-binding warheads were developed with potential SEGRA properties to improve their clinical safety profile for long-lasting topical skin disease applications. Since the off-rate of a covalently binding drug is negligible compared to that of a non-covalent drug, its therapeutic effects can be prolonged and typically, smaller doses of the drug are necessary to reach the same level of therapeutic efficacy, thereby potentially reducing systemic side effects. Different analogs of SEGRA GSK866 coupled to cysteine reactive warheads were characterized for GR potency and selectivity in various biochemical and cellular assays. GR- and NFκB-dependent reporter gene studies show favorable anti-inflammatory properties with reduced GR transactivation of two non-steroidal GSK866 analogs UAMC-1217 and UAMC-1218, whereas UAMC-1158 and UAMC-1159 compounds failed to modulate cellular GR activity. These results were further supported by GR immuno-localization and S211 phospho-GR western analysis, illustrating significant GR phosphoactivation and nuclear translocation upon treatment of GSK866, UAMC-1217, or UAMC-1218, but not in case of UAMC-1158 or UAMC-1159. Furthermore, mass spectrometry analysis of tryptic peptides of recombinant GR ligand-binding domain (LBD) bound to UAMC-1217 or UAMC-1218 confirmed covalent cysteine-dependent GR binding. Finally, molecular dynamics simulations, as well as glucocorticoid receptor ligand-binding domain (GR-LBD) coregulator interaction profiling of the GR-LBD bound to GSK866 or its covalently binding analogs UAMC-1217 or UAMC-1218 revealed subtle conformational differences that might underlie their SEGRA properties. Altogether, GSK866 analogs UAMC-1217 and UAMC-1218 hold promise as a novel class of covalent-binding SEGRA ligands for the treatment of topical inflammatory skin disorders.
- Published
- 2017
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44. First-void urine: A potential biomarker source for triage of high-risk human papillomavirus infected women.
- Author
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Van Keer S, Pattyn J, Tjalma WAA, Van Ostade X, Ieven M, Van Damme P, and Vorsters A
- Subjects
- Biomarkers urine, Disease Progression, Female, Humans, Papillomavirus Infections urine, Triage, Uterine Cervical Neoplasms urine, Uterine Cervical Dysplasia urine, Human papillomavirus 16 isolation & purification, Human papillomavirus 18 isolation & purification, Papillomavirus Infections diagnosis, Uterine Cervical Neoplasms diagnosis, Uterine Cervical Dysplasia diagnosis
- Abstract
Great interest has been directed towards the use of first-void urine as a liquid biopsy for high-risk human papillomavirus DNA testing. Despite the high correlations established between urinary and cervical infections, human papillomavirus testing is unable to distinguish between productive and transforming high-risk infections that have the tendency to progress to cervical cancer. Thus far, investigations have been primarily confined to the identification of biomarkers for triage of high-risk human papillomavirus-positive women in cervicovaginal specimens and tissue biopsies. This paper reviews urinary biomarkers for cervical cancer and triage of high-risk human papillomavirus infections and elaborates on the opportunities and challenges that have emerged regarding the use of first-void urine as a liquid biopsy for the analysis of both morphological- (conventional cytology and novel immunohistochemical techniques) and molecular-based (HPV16/18 genotyping, host/viral gene methylation, RNA, and proteins) biomarkers. A literature search was performed in PubMed and Web of Science for studies investigating the use of urine as a biomarker source for cervical cancer screening. Five studies were identified reporting on biomarkers that are still in preclinical exploratory or clinical assay development phases and on assessments of non-invasive (urine) samples. Although large-scale validation studies are still needed, we conclude that methylation of both host and viral genes in urine has been proven feasible for use as a molecular cervical cancer triage and screening biomarker in phase two studies. This is especially promising and underscores our hypothesis that human papillomavirus DNA and candidate human and viral biomarkers are washed away with the initial, first-void urine, together with exfoliated cells, debris and impurities that line the urethra opening. Similar to the limitations of self-collected cervicovaginal samples, first-void urine will likely not fulfil the high-quality cellularity standards required for morphological biomarkers. Molecular biomarkers will likely overcome this issue to yield high-throughput, objective, and reproducible results. When using proper sampling, transport, storage, preanalytical biomarker concentration techniques, and clinically validated assays, first-void urine is expected to be a valuable source of molecular biomarkers for cervical cancer screening. Furthermore, as first-void urine can be easily and non-invasively collected, it is a highly preferred technique among women and offers the ability to test both primary high-risk human papillomavirus and biomarkers in the same sample. In addition, the use of first-void urine confers opportunities to reduce loss-to follow-up and non-adherence to screening subjects., (Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
45. Molecular insights into cancer therapeutic effects of the dietary medicinal phytochemical withaferin A.
- Author
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Chirumamilla CS, Pérez-Novo C, Van Ostade X, and Vanden Berghe W
- Subjects
- Animals, Cell Cycle Checkpoints drug effects, Cell Line, Tumor, Disease Models, Animal, Humans, Molecular Structure, Protein Conformation, Neoplasms drug therapy, Phytochemicals pharmacology, Withanolides pharmacology
- Abstract
Despite the worldwide research efforts to combat cancer, it remains a leading cause of death. Although various specific kinase inhibitors already have been approved for clinical cancer treatment, occurrence of intrinsic or acquired resistance and intermittent response over longer periods limits long-term success of single kinase-targeted therapies. In this respect, there is a renewed interest in polypharmaceutical natural compounds, which simultaneously target various hyperactivated kinases involved in tumour-inflammation, angiogenesis, cell survival, proliferation, metastasis and angiogenesis. The dietary medicinal phytochemical withaferin A (WA), isolated from Withaferin somnifera (popular Indian name Ashwagandha), holds promise as a novel anti-cancer agent, which targets multiple cell survival kinase pathways, including IκB kinase/NF-κB, PI3 kinase/protein kinase B/mammalian target of rapamycin and mitogen-activated protein kinase/extracellular signal-regulated kinase amongst others. In this review, we propose a novel mechanism of WA-dependent kinase inhibition via electrophilic covalent targeting of cysteine residues in conserved kinase activation domains (kinase cysteinome), which could underlie its pleiotropic therapeutic effects in cancer signalling.
- Published
- 2017
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- View/download PDF
46. Characterizing the Syphilis-Causing Treponema pallidum ssp. pallidum Proteome Using Complementary Mass Spectrometry.
- Author
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Osbak KK, Houston S, Lithgow KV, Meehan CJ, Strouhal M, Šmajs D, Cameron CE, Van Ostade X, Kenyon CR, and Van Raemdonck GA
- Subjects
- Animals, Rabbits, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Syphilis microbiology, Tandem Mass Spectrometry, Bacterial Proteins genetics, Proteome analysis, Treponema pallidum genetics
- Abstract
Background: The spirochete bacterium Treponema pallidum ssp. pallidum is the etiological agent of syphilis, a chronic multistage disease. Little is known about the global T. pallidum proteome, therefore mass spectrometry studies are needed to bring insights into pathogenicity and protein expression profiles during infection., Methodology/principal Findings: To better understand the T. pallidum proteome profile during infection, we studied T. pallidum ssp. pallidum DAL-1 strain bacteria isolated from rabbits using complementary mass spectrometry techniques, including multidimensional peptide separation and protein identification via matrix-assisted laser desorption ionization-time of flight (MALDI-TOF/TOF) and electrospray ionization (ESI-LTQ-Orbitrap) tandem mass spectrometry. A total of 6033 peptides were detected, corresponding to 557 unique T. pallidum proteins at a high level of confidence, representing 54% of the predicted proteome. A previous gel-based T. pallidum MS proteome study detected 58 of these proteins. One hundred fourteen of the detected proteins were previously annotated as hypothetical or uncharacterized proteins; this is the first account of 106 of these proteins at the protein level. Detected proteins were characterized according to their predicted biological function and localization; half were allocated into a wide range of functional categories. Proteins annotated as potential membrane proteins and proteins with unclear functional annotations were subjected to an additional bioinformatics pipeline analysis to facilitate further characterization. A total of 116 potential membrane proteins were identified, of which 16 have evidence supporting outer membrane localization. We found 8/12 proteins related to the paralogous tpr gene family: TprB, TprC/D, TprE, TprG, TprH, TprI and TprJ. Protein abundance was semi-quantified using label-free spectral counting methods. A low correlation (r = 0.26) was found between previous microarray signal data and protein abundance., Conclusions: This is the most comprehensive description of the global T. pallidum proteome to date. These data provide valuable insights into in vivo T. pallidum protein expression, paving the way for improved understanding of the pathogenicity of this enigmatic organism., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2016
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47. IPA Analysis of Cervicovaginal Fluid from Precancerous Women Points to the Presence of Biomarkers for the Precancerous State of Cervical Carcinoma.
- Author
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Van Ostade X, Dom M, and Van Raemdonck G
- Abstract
Despite large gaps in our knowledge on the intracellular mechanism leading to cervical cancer, the pathways induced by oncogenic high-risk Human Papilloma Virus (HPV) and those finally causing cervical cancer are increasingly being unraveled. Assuming that precancerous tissue is recognized and lysed by the immune system-which is in many cases incomplete because of the counteraction by the HPV virus-we hypothesize that several intracellular factors, involved in induction and development of precancerous lesions and/or cervical cancer are being released into the cervicovaginal fluid (CVF). These factors can then be seen as markers for the precancerous state, and when they persist they are indicative for an increased risk for cervical carcinoma. In a previous study, we analyzed the proteomic profiles of six CVF samples from women with different stages of precancerous lesions and compared these with the CVF proteomes from healthy women. Here, we extend these observations by investigating these proteomes by Ingenuity Pathway Analysis (IPA). We show that proteins in CVF from precancerous women are clearly more involved in pathways that make up the 'hallmarks of cancer', as compared to CVF proteins from healthy persons. Moreover, after literature search, proteins classified by IPA in the 'cancer' category, were more correlated with cervical cancer when they originated from CVF from precancerous women. Many of these proteins formed a network with angiotensin II as central mediator. The search for 'network biomarkers', rather than single biomarkers, could drastically increase specificity, sensitivity and prognostic value of cervical cancer diagnosis, making use of an easy to handle fluid, the CVF.
- Published
- 2014
- Full Text
- View/download PDF
48. Increased Serpin A5 levels in the cervicovaginal fluid of HIV-1 exposed seronegatives suggest that a subtle balance between serine proteases and their inhibitors may determine susceptibility to HIV-1 infection.
- Author
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Van Raemdonck G, Zegels G, Coen E, Vuylsteke B, Jennes W, and Van Ostade X
- Subjects
- Cote d'Ivoire epidemiology, Female, Gene Expression Regulation, Enzymologic immunology, Genetic Predisposition to Disease, HIV Infections epidemiology, HIV Infections virology, Humans, Protein C Inhibitor chemistry, Protein C Inhibitor genetics, Serine Endopeptidases genetics, Serine Endopeptidases metabolism, Serine Proteases genetics, Sex Workers, Body Fluids enzymology, HIV Infections immunology, HIV-1 physiology, Protein C Inhibitor metabolism, Serine Proteases metabolism
- Abstract
HIV-exposed seronegative individuals (HESNs) are persons who remain seronegative despite repeated exposure to HIV, suggesting an in vivo resistance mechanism to HIV. Elucidation of endogenous factors responsible for this phenomenon may aid in the development of new classes of microbicides and therapeutics. We compared cervicovaginal protein abundance profiles between high-risk HESN and two control groups: low-risk HESN and HIV-positives. Four iTRAQ-based quantitative experiments were performed using samples classified based on presence/absence of particular gynaecological conditions. After statistical analysis, two proteins were shown to be differentially abundant between high-risk HESNs and control groups. Serpin A5, a serine proteinase inhibitor and Myeloblastin, a serine protease, were up- and downregulated, respectively. Commercially available ELISA assays were used to confirm differential Serpin A5 levels. These results suggest that HIV resistance in CVF of HESNs is the result of a delicate balance between two complementary mechanisms: downregulation of serine proteinases and upregulation of their inhibitors., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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49. Expression analysis of LEDGF/p75, APOBEC3G, TRIM5alpha, and tetherin in a Senegalese cohort of HIV-1-exposed seronegative individuals.
- Author
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Mous K, Jennes W, Camara M, Seydi M, Daneau G, Mboup S, Kestens L, and Van Ostade X
- Subjects
- APOBEC-3G Deaminase, Adult, Antigens, CD genetics, Antiviral Restriction Factors, Carrier Proteins genetics, Cytidine Deaminase genetics, Environmental Exposure, Female, GPI-Linked Proteins genetics, GPI-Linked Proteins metabolism, HIV Infections genetics, HIV Infections immunology, Humans, Intercellular Signaling Peptides and Proteins genetics, Leukocytes, Mononuclear metabolism, Lymphocyte Activation immunology, Male, Middle Aged, Monocytes metabolism, RNA, Messenger metabolism, Senegal, T-Lymphocytes metabolism, Tripartite Motif Proteins, Ubiquitin-Protein Ligases, Antigens, CD metabolism, Carrier Proteins metabolism, Cytidine Deaminase metabolism, HIV Infections metabolism, HIV Seronegativity physiology, HIV-1 immunology, Intercellular Signaling Peptides and Proteins metabolism
- Abstract
Background: HIV-1 replication depends on a delicate balance between cellular co-factors and antiviral restriction factors. Lens epithelium-derived growth factor (LEDGF/p75) benefits HIV, whereas apolipoprotein B mRNA-editing catalytic polypeptide-like 3G (APOBEC3G), tripartite motif 5alpha (TRIM5α), and tetherin exert anti-HIV activity. Expression levels of these proteins possibly contribute to HIV-1 resistance in HIV-1-exposed populations., Methodology/principal Findings: We used real-time PCR and flow cytometry to study mRNA and protein levels respectively in PBMC and PBMC subsets. We observed significantly reduced LEDGF/p75 protein levels in CD4+ lymphocytes of HIV-1-exposed seronegative subjects relative to healthy controls, whereas we found no differences in APOBEC3G, TRIM5α, or tetherin expression. Untreated HIV-1-infected patients generally expressed higher mRNA and protein levels than healthy controls. Increased tetherin levels, in particular, correlated with markers of disease progression: directly with the viral load and T cell activation and inversely with the CD4 count., Conclusions/significance: Our data suggest that reduced LEDGF/p75 levels may play a role in resistance to HIV-1 infection, while increased tetherin levels could be a marker of advanced HIV disease. Host factors that influence HIV-1 infection and disease could be important targets for new antiviral therapies.
- Published
- 2012
- Full Text
- View/download PDF
50. Intracellular detection of differential APOBEC3G, TRIM5alpha, and LEDGF/p75 protein expression in peripheral blood by flow cytometry.
- Author
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Mous K, Jennes W, De Roo A, Pintelon I, Kestens L, and Van Ostade X
- Subjects
- APOBEC-3G Deaminase, Antiviral Restriction Factors, Carrier Proteins genetics, Carrier Proteins immunology, Cytidine Deaminase genetics, Cytidine Deaminase immunology, HIV Infections virology, HIV-1 genetics, HIV-1 metabolism, Humans, Intercellular Signaling Peptides and Proteins genetics, Intercellular Signaling Peptides and Proteins immunology, RNA, Messenger genetics, Reproducibility of Results, Reverse Transcriptase Polymerase Chain Reaction, Statistics, Nonparametric, Tripartite Motif Proteins, Ubiquitin-Protein Ligases, Virus Replication, Carrier Proteins biosynthesis, Cytidine Deaminase biosynthesis, Flow Cytometry methods, HIV Infections blood, HIV-1 physiology, Intercellular Signaling Peptides and Proteins biosynthesis, Leukocytes, Mononuclear immunology
- Abstract
Expression studies on specific host proteins predominantly use quantitative PCR and western blotting assays. In this study, we optimized a flow cytometry-based assay to study intracellular expression levels of three important host proteins involved in HIV-1 replication: apolipoprotein B mRNA-editing catalytic polypeptide-like 3G (APOBEC3G), tripartite motif 5alpha (TRIM5α), and lens epithelium-derived growth factor (LEDGF/p75). An indirect intracellular staining (ICS) method was optimized using antibodies designed for other applications like enzyme-linked immunosorbent assay (ELISA), confocal imaging, and western blotting. The median fluorescence intensity (MFI) value--a measure for the protein expression level--increased upon higher antibody concentration and longer incubation time, and was reduced following preincubation with recombinant proteins. Staining of stably transfected or knock-down cell lines supported the method's specificity. Moreover, confocal microscopy analysis of peripheral blood mononuclear cells (PBMC), when stained according to the ICS method, confirmed the localization of APOBEC3G and TRIM5α in the cytoplasm, and of LEDGF/p75 in the nucleus. Also, stimulation with mitogen, interferon-alpha, or interferon-beta resulted in detectable, albeit weak, increases in intracellular expression of APOBEC3G and TRIM5α. After optimization, the method was applied to healthy control and HIV-1 infected subjects. For all subjects studied, the memory subset of CD4+ T cells showed significantly higher expression levels of APOBEC3G, TRIM5α, and LEDGF/p75, while the CD16+ subset of monocytes was characterized by higher expression levels of LEDGF/p75. In addition, we observed that therapy-naïve HIV-1 patients tended to have lower expression levels of APOBEC3G and TRIM5α than HIV-1 negative controls. In summary, our data provide proof-of-principle for the detection of specific host factors at the level of a single cell, which may prove useful for our further understanding of their role in virus-host interactions., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
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