References of "Antoine, Nadine"
     in
Bookmark and Share    
See detailDistribution of nerve fibers and prion protein expression in mouse Peyer's patches
Defaweux, Valérie ULg; Dorban, G; Demonceau, C et al

Poster (2004, July)

Detailed reference viewed: 7 (3 ULg)
Full Text
Peer Reviewed
See detailFDC-B1: a new monoclonal antibody directed against bovine follicular dendritic cells
Defaweux, Valérie ULg; Mélot, France ULg; Jolois, Olivier ULg et al

in Veterinary Immunology and Immunopathology (2004), 97(1-2), 1-9

Follicular dendritic cells (FDCs) are a unique population of accessory cells located in the light zone of the germinal centres of lymphoid follicles. Their involvement in the generation of Immoral immune ... [more ▼]

Follicular dendritic cells (FDCs) are a unique population of accessory cells located in the light zone of the germinal centres of lymphoid follicles. Their involvement in the generation of Immoral immune responses implies a potential role for these cells in many disorders. Indeed, in prion diseases, FDCs seem to be the major sites of extraneuronal cellular prion protein expression and the principal sites of the infectious agent accumulation in lymphoid organs. The identification of FDC is useful for the analysis of their distribution in reactive lymphoid tissue as well as in pathological conditions. The production and characterisation of a new mouse monoclonal antibody directed against bovine follicular dendritic cells (FDC-B1) is reported. The antigen detected by FDC-B1 is expressed exclusively on the surface of FDCs in ruminant lymphoid organs. The antigen has an approximate molecular weight of 28 kDa. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 55 (20 ULg)
Full Text
Peer Reviewed
See detailMorphology, growth and modelling of bone tissue
Toppets, Vinciane ULg; Pastoret, V.; De Behr, V. et al

in Annales de Médecine Vétérinaire (2004), 148(1), 1-13

Bone is an essential part of the squeletton. Besides its mechanic properties, bone has an important role in metabolism regulation because it acts as a reservoir for the storage of minerals essential to ... [more ▼]

Bone is an essential part of the squeletton. Besides its mechanic properties, bone has an important role in metabolism regulation because it acts as a reservoir for the storage of minerals essential to provide homeostasy. This article describes bone morphology and different ways of classification of this tissue. It gives the composition of organic and mineral extracellular bone matrix, underlines the dynamic character of bone tissue, details the cellular morphology and the metabolism of the elements acting on the synthesis/resorption mechanisms : osteoprogenitor cells, osteoblasts, osteocyts and osteoclasts. It relates the histogenesis of bone tissue and develops the different types of ossification: intramembranous, periostic, endochondral and osteonal remodeling. The last part of this article describe some dietetary and hormonal influences on bone tissue. [less ▲]

Detailed reference viewed: 46 (10 ULg)
Peer Reviewed
See detailDistribution of nerve fibres and prion protein expression in mice Peyer’s patches
Defaweux, Valérie ULg; Dorban, G.; Demonceau, C. et al

Poster (2003, October)

Prion pathogenesis following oral exposure is thought to involve gut-associated lymphoid tissue, which includes Peyer’s patches (PP). The antigens enter into the underlying lymphoid tissue organized in PP ... [more ▼]

Prion pathogenesis following oral exposure is thought to involve gut-associated lymphoid tissue, which includes Peyer’s patches (PP). The antigens enter into the underlying lymphoid tissue organized in PP through the medium of M cells. Infectious prion protein (PrPres) would probably take the same way of entry and like this initiate the first stage of lympho-invasion. Theoretically, intestinal lymphoid cells can come in contact with ingested PrPres and with nerve endings of the intramural system. The distribution pattern of the nerve fibres and lymphoid cells in PP and possible contact between these two elements implicated in neuroinvasion are not yet fully elucidated. In our study, classical immunoperoxydase staining and double immunofluorescence staining analysed with a confocal microscope has been carried out on C56Bl/6 mice PP. Immunoperoxidase and immunofluorescent CD11c stainings show numerous dendritic cells (DC) in the suprafollicular dome, close to the epithelium made of enterocytes and M-cells. Confocal studies show the presence of DC in the T cell zones of Peyer's patches, and also close to B cells in the follicule and to follicular dendritic cells (FDC) in the germinal centres. The PrPc expression, fundamental in the pathogenesis of prion diseases, is notably localized in germinal centres, co-localized with the FDC network and on cellular structures close to the epithelium, co-localized with DC. Nerve fibres have been immunostained in fluorescence using antibodies raised against neurofilaments High, Medium and Low and against glial fibrillary acidic protein (GFAP). Only GFAP staining revealed the presence of some nerve fibres in the suprafollicular dome, coursing the mucosal epithelium and also at the periphery of germinal centres in close connection with numerous dendritic cells. Such results permit us to postulate that these nerve fibres and PrPc positive dendritic cells, strategically positioned under the intestinal epithelium as well as in the germinal centres close to FDC network, highly expressing PrPc and thought to replicate PrPres, may be involved in the peripheral transport of the infectious prion protein. [less ▲]

Detailed reference viewed: 17 (5 ULg)
Peer Reviewed
See detailFDC-B1, a new monoclonal antibody directed against bovine follicular dendrititic cells.
Defaweux, Valérie ULg; Mélot, France ULg; Jolois, Olivier ULg et al

Poster (2003, March)

Follicular dendritic cells (FDCs) are unique immunological accessory cells located in the light and dark zones of the germinal centres in lymph follicles. Characterized by long branching processes forming ... [more ▼]

Follicular dendritic cells (FDCs) are unique immunological accessory cells located in the light and dark zones of the germinal centres in lymph follicles. Characterized by long branching processes forming a three-dimensional network, FDCs create particular microenvironments for germinal centre B and T cells and contribute to the maturation of B cells into memory cells. An involvement of the FDCs is suspected in various disorders affecting lymphoid tissues, malignant lymphoma or in some viral diseases. Moreover, in prion diseases, FDCs seem to be the major sites of extraneuronal cellular prion protein expression and the principal sites of the infectious agent accumulation in lymph organs. Because no antibody commercially available was specific to bovine FDCs, a new monoclonal antibody directed against bovine FDCs (FDC-B1) has been produced and characterized in our laboratory. The antigen detected by FDC-B1 is expressed on FDC surfaces in ruminant (bovine, ovine and caprine) lymphoid organs. This protein seems to be a membrane glycoprotein of more or less 28 kDa whose sequence will be soon determined. Moreover, FDC-B1 can be used in various applications: immunofluorescence, immunoperoxidase, immunogold labellings and western blotting. FDCs are potential targets for therapy or prophylaxis in natural TSEs, such as bovine spongiform encephalopathies and scrapie. Thus, it appears of great interest to identify bovine and ovine FDCs in routine lymphoid tissues sections. An other application of this antibody to immunofluorescence histochemistry techniques will enable the study of possible direct contacts between bovine FDCs and nerve endings and thus clarify prions neuroinvasion scheme in the case of BSE and scrapie. [less ▲]

Detailed reference viewed: 10 (1 ULg)
Full Text
Peer Reviewed
See detailDo Bovine Lymphocytes Express a Peculiar Prion Protein?
Mélot, France ULg; Thielen, Caroline ULg; Labiet, T. et al

in Developmental Immunology (2002), 9(4), 245-52

The cellular prion protein (PrPc) is a glycolipid-anchored cell surface protein that usually exhibits three glycosylation states. Its post-translationally modified isoform, PrPsc, is involved in the ... [more ▼]

The cellular prion protein (PrPc) is a glycolipid-anchored cell surface protein that usually exhibits three glycosylation states. Its post-translationally modified isoform, PrPsc, is involved in the pathogenesis of various transmissible spongiform encephalopathies (TSEs). In bovine species, BSE infectivity appears to be restricted to the central nervous system; few or no detectable infectivity is found in lymphoid tissues in contrast to scrapie or variant CJD. Since expression of PrPc is a prerequisite for prion replication, we have investigated PrPc expression by bovine immune cells. Lymphocytes from blood and five different lymph organs were isolated from the same animal to assess intra- and interindividual variability of PrPc expression, considering six individuals. As shown by flow cytometry, this expression is absent or weak on granulocytes but is measurable on monocytes, B and T cells from blood and lymph organs. The activation of the bovine cells produces an upregulation of PrPc. The results of our in vitro study of PrPc biosynthesis are consistent with previous studies in other species. Interestingly, western blotting experiments showed only one form of the protein, the diglycosylated band. We propose that the glycosylation state could explain the lack of infectivity of the bovine immune cells. [less ▲]

Detailed reference viewed: 43 (11 ULg)
Full Text
Peer Reviewed
See detailDNA immunisation. New histochemical and morphometric data.
Ehirchiou, D.; Zorzi, Willy ULg; Biemans, R. et al

in European Journal of Histochemistry (2002), 46(3), 215-22

Splenic germinal center reactions were measured during primary response to a plasmidic DNA intramuscular injection. Cardiotoxin-pretreated Balb/c mice were immunized with DNA plasmids encodmg or not the ... [more ▼]

Splenic germinal center reactions were measured during primary response to a plasmidic DNA intramuscular injection. Cardiotoxin-pretreated Balb/c mice were immunized with DNA plasmids encodmg or not the SAG1 protein, a membrane antigen of Toxoplasma gondii. Specific anti-SAG1 antibodies were detected on days 16 and 36 after injection of coding plasmids. The results of ELISAs showed that the SAG1-specific antibodies are of the IgG2a class. Morphometric analyses were done on serial immunostained cryosections of spleen and draining or non-draining lymph nodes. This new approach made it possible to evaluate the chronological changes induced by DNA immunisation in the germinal centres (in number and in size). Significant increases in the number of germinal centres were measured in the spleen and only in draining lymph nodes after plasmid injection, the measured changes of the germinal centers appeared to result from the adjuvant stimulatory effect of the plasmidic DNA since both the coding and the noncoding plasmid DNA induced them. No measurable changes were recorded in the T-dependent zone of lymph organs. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Peer Reviewed
See detailNew Histochemical and Ultrastructural Observations on Normal Bovine Tonsils
Velinova, Maria; Thielen, Caroline ULg; Mélot, France ULg et al

in Veterinary Record : Journal of the British Veterinary Association (2001), 149(20), 613-7

Samples of normal bovine palatine tonsils were examined by light and electron microscopy. Like human tonsils, they were composed of crypts, subepithelial areas, follicles, and T-dependent zones, but their ... [more ▼]

Samples of normal bovine palatine tonsils were examined by light and electron microscopy. Like human tonsils, they were composed of crypts, subepithelial areas, follicles, and T-dependent zones, but their well-developed capsule subdivided the lymphoid tissue by connective septa. B cells formed the major lymphoid component. The follicles and T-dependent zones had morphological and histochemical features typical of peripheral lymph organs. Follicular dendritic cells were isolated and shown to be similar to human follicular dendritic cells. [less ▲]

Detailed reference viewed: 19 (5 ULg)
Full Text
Peer Reviewed
See detailIsolation of Bovine Follicular Dendritic Cells Allows the Demonstration of a Particular Cellular Prion Protein
Thielen, Caroline ULg; Mélot, France ULg; Jolois, Olivier ULg et al

in Cell & Tissue Research (2001), 306(1), 49-55

As interaction of cellular prion protein (PrPc) and the infectious agent (PrPres) appears to be a crucial pathogenic step promoted by homology, variation in PrPc isoforms on bovine immune cells may ... [more ▼]

As interaction of cellular prion protein (PrPc) and the infectious agent (PrPres) appears to be a crucial pathogenic step promoted by homology, variation in PrPc isoforms on bovine immune cells may explain the absence of infectivity in most bovine lymph organs. In this study, we examined PrPc expression in bovine lymph organs (tonsils and lymph nodes) and on isolated follicular dendritic cells (FDCs). We used a panel of different monoclonal antibodies (MoAbs) raised against different epitopes of prion protein. Two MoAbs recognise amino acids 79-92 (SAF 34 and SAF 32 Mo-Abs); the 6H4 antibody reacts with a specific peptide comprising the 144-152 amino acids, and the 12F10 MoAb recognises the sequence 142-160. After immunolabelling of frozen sections of lymph organs with 6H4 or 12F10 MoAbs, we detected cellular prion protein in germinal centres. However, using the SAF 34 or SAF 32 antibodies, PrPc was revealed outside the lymphoid tissues. No PrPc was observed in the germinal centres. Therefore, we adapted the method of FDC isolation, making it suitable for the study of PrPc expression on their surface. Using electron microscopy, the presence of PrPc on the surface of FDCs was demonstrated only with 6H4 MoAb. These results suggest that bovine follicular dendritic cells express a particular form of prion protein. Either the N-terminal part of PrPc is cleaved or the accessibility of the specific epitope (79-92) of SAF 34 MoAb is abolished by interaction with other molecules. This particular isoform of PrPc on bovine FDCs might be related to the apparent absence of infectivity in lymph organs in cattle affected by bovine spongiform encephalopathy. [less ▲]

Detailed reference viewed: 35 (9 ULg)
Peer Reviewed
See detailLocation and Phenotype of Proliferating T cells in Secondary Lymph Follicles
Hoshi, S.; Bouzahzah, F.; Mancini, I. et al

in Journal of Clinical and Experimental Hematopathology [=JCEH] (2001), 42

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailHuman Fdc Express Prpc in Vivo and in Vitro
Thielen, Caroline ULg; Antoine, Nadine ULg; Mélot, France ULg et al

in Developmental Immunology (2001), 8(3-4), 259-66

Prion diseases are fatal neurodegenerative disorders caused by accumulation of abnormal prion protein (protease-resistant prion, PrPres). PrPres accumulation is also detected in lymphoid organs after ... [more ▼]

Prion diseases are fatal neurodegenerative disorders caused by accumulation of abnormal prion protein (protease-resistant prion, PrPres). PrPres accumulation is also detected in lymphoid organs after peripheral infection. Several studies suggest that follicular dendritic cells (FDC) could be the site of PrPres retention and amplification. Here we show that human follicular dendritic cells can express normal cellular prion protein (PrPc) both in situ and in vitro. When tonsillar cryosections were treated with anti-PrP antibody, the label was found on some very delicate cell extensions inside the lymphoid follicles, especially in the germinal centres. These extensions react with DRC1 antibody, used frequently to label FDC. Other structures labelled with anti-PrP antibody were the keratinocytes. To confirm the ability of FDC to synthesise PrPc, we isolated FDC by a non-enzymatic procedure and cultured them. By cytochemistry and flow cytometry it was clearly shown that FDC do produce PrPc. [less ▲]

Detailed reference viewed: 16 (2 ULg)
Full Text
Peer Reviewed
See detailBone Sialoprotein Mrna and Protein Expression in Human Multiple Myeloma Cell Lines and Patients
Bellahcene, Akeila ULg; Van Riet, I.; de Greef, C. et al

in British Journal of Haematology (2000), 111(4), 1118-21

Bone sialoprotein (BSP) is a glycoprotein essentially found in mineralizing connective tissues. We have recently demonstrated that BSP is ectopically expressed by carcinomas that metastasize to bone with ... [more ▼]

Bone sialoprotein (BSP) is a glycoprotein essentially found in mineralizing connective tissues. We have recently demonstrated that BSP is ectopically expressed by carcinomas that metastasize to bone with high frequency. Multiple myeloma (MM) is characterized by the localization of tumour plasma cells in the bone marrow. In this study, BSP expression was evaluated in human myeloma cell lines and in bone marrow aspirates and one ascites fluid from MM patients. BSP was detectable in conditioned media of MM cell lines. Using FACS analysis and in situ hybridization, we demonstrated that tumour cells from all MM patients and cell lines analysed express BSP at both the protein and the mRNA level. [less ▲]

Detailed reference viewed: 22 (3 ULg)
Full Text
Peer Reviewed
See detailDifferential Expression of Cellular Prion Protein on Human Blood and Tonsil Lymphocytes
Antoine, Nadine ULg; Cesbron, J. Y.; Coumans, Bernard ULg et al

in Haematologica (2000), 85(5), 475-80

BACKGROUND AND OBJECTIVE: The expression of cellular prion protein (PrPc) on the surface of peripheral lymphocytes has been previously reported, but little is known about its expression on lymphoid cells ... [more ▼]

BACKGROUND AND OBJECTIVE: The expression of cellular prion protein (PrPc) on the surface of peripheral lymphocytes has been previously reported, but little is known about its expression on lymphoid cells from secondary lymph organs. In this report, we compare the surface expression of PrPc on human blood lymphocytes and tonsil lymphocytes. DESIGN AND METHODS: This analysis was performed by cytometry on live lymphocytes isolated from healthy donors or from the tonsils of adults or children. RESULTS: Human peripheral lymphocytes and tonsillar lymphoid cells, but not erythrocytes or granulocytes, express PrPc at their surfaces. Interestingly, we found significantly less PrPc on freshly isolated tonsil lymphocytes, both B and T, than on blood cells. Although tonsil cells bear less PrPc than circulating blood lymphocytes, they are able to express high quantities of PrPc on their surface when placed in culture. However, contrary to previous results, mitogen stimulation does not affect this expression on B- or T-cells. INTERPRETATION AND CONCLUSIONS: We suggest that the PrPc expression by lymphocytes may be modified by interactions occurring during intratissular migration or during cell-to-cell contacts. Whether PrPc plays a role in intracellular communication at this location, as it does in the nervous system, remains an open question. [less ▲]

Detailed reference viewed: 30 (4 ULg)
Peer Reviewed
See detailTnp-470, a Potent Angiogenesis Inhibitor, Amplifies Human T Lymphocyte Activation through an Induction of Nuclear Factor-Kappab, Nuclear Factor-at, and Activation Protein-1 Transcription Factors
Locigno, Roberto; Antoine, Nadine ULg; Bours, Vincent ULg et al

in Laboratory Investigation : Journal of Technical Methods & Pathology (2000), 80(1), 13-21

TNP-470, an angiogenesis inhibitor derived from fumagillin, is foreseen as a promising anti-cancer drug. Its effectiveness to restrain tumor growth and its lack of major side effects have been ... [more ▼]

TNP-470, an angiogenesis inhibitor derived from fumagillin, is foreseen as a promising anti-cancer drug. Its effectiveness to restrain tumor growth and its lack of major side effects have been demonstrated in several animal models and have led the drug to reach phase III clinical trials. Beside its antiangiogenesis activities, TNP-470 exhibits several effects on the immune system. We had shown previously that TNP-470 stimulated B lymphocyte proliferation through an action on T cells. In this study, we examined the cellular and molecular modifications induced by TNP-470 in normal human T lymphocytes. Transmission electron microscopic examination of PHA/TNP-470-treated T cells revealed significant morphologic modifications when compared with PHA-treated control T cells. TNP-470 induced indeed an important and significant increase of the nuclear size as well as major nuclear chromatin decondensation. This observation indicated that TNP-470 amplified T-cell activation and led us to investigate its effects on the activation of transcription factors involved in T-cell activation. Using electrophoretic mobility shift assays, we have demonstrated that TNP-470 amplifies and extends the DNA-binding activity of nuclear factor-AT, nuclear factor-KB, and activation protein-1 in T cells. Furthermore, the angioinhibin significantly increased the secretion of IL-2 and IL-4. Our data demonstrate that TNP-470 amplifies the activation of T cells. This effect, whose molecular mechanisms remain to be elucidated, has to be taken into account in the assessment of the antitumor effect of the drug. [less ▲]

Detailed reference viewed: 26 (0 ULg)