22 results on '"Nys, Kris"'
Search Results
2. Plasma cells are not restricted to the CD27+ phenotype:characterization of CD27-CD43+ antibody-secreting cells
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Covens, Kris, Verbinnen, Bert, de Jong, Britt G., Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, van Dongen, Jacques J.M., van Zelm, Menno C., Bossuyt, Xavier, Covens, Kris, Verbinnen, Bert, de Jong, Britt G., Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, van Dongen, Jacques J.M., van Zelm, Menno C., and Bossuyt, Xavier
- Abstract
Circulating antibody-secreting cells are present in the peripheral blood of healthy individuals reflecting the continued activity of the humoral immune system. Antibody-secreting cells typically express CD27. Here we describe and characterize a small population of antibody-secreting class switched CD19+CD43+ B cells that lack expression of CD27 in the peripheral blood of healthy subjects. In this study, we characterized CD27-CD43+ cells. We demonstrate that class-switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphologically similar to antibody-secreting cells, show downregulation of B cell differentiation markers, and have a gene expression profile related to conventional plasmablasts. Despite these similarities, we observed differences in IgA and IgG subclass distribution, expression of homing markers, replication history, frequency of somatic hypermutation, immunoglobulin repertoire, gene expression related to Toll-like receptors, cytokines, and cytokine receptors, and antibody response to vaccination. Their frequency is altered in immune-mediated disorders. Conclusion: we characterized CD27-CD43+ cells as antibody-secreting cells with differences in function and homing potential as compared to conventional CD27+ antibody-secreting cells.
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- 2023
3. Plasma cells are not restricted to the CD27+ phenotype: characterization of CD27-CD43+ antibody-secreting cells
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KU Leuven, Flemish Department of Economy, Science and Innovation (Belgium), Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, Bossuyt, Xavier, KU Leuven, Flemish Department of Economy, Science and Innovation (Belgium), Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, and Bossuyt, Xavier
- Abstract
Circulating antibody-secreting cells are present in the peripheral blood of healthy individuals reflecting the continued activity of the humoral immune system. Antibody-secreting cells typically express CD27. Here we describe and characterize a small population of antibody-secreting class switched CD19+CD43+ B cells that lack expression of CD27 in the peripheral blood of healthy subjects. In this study, we characterized CD27-CD43+ cells. We demonstrate that class-switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphologically similar to antibody-secreting cells, show downregulation of B cell differentiation markers, and have a gene expression profile related to conventional plasmablasts. Despite these similarities, we observed differences in IgA and IgG subclass distribution, expression of homing markers, replication history, frequency of somatic hypermutation, immunoglobulin repertoire, gene expression related to Toll-like receptors, cytokines, and cytokine receptors, and antibody response to vaccination. Their frequency is altered in immune-mediated disorders.
- Published
- 2023
4. Table_1_Plasma cells are not restricted to the CD27+ phenotype: characterization of CD27-CD43+ antibody-secreting cells.docx [Dataset]
- Author
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Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, Bossuyt, Xavier, Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, and Bossuyt, Xavier
- Abstract
Circulating antibody-secreting cells are present in the peripheral blood of healthy individuals reflecting the continued activity of the humoral immune system. Antibody-secreting cells typically express CD27. Here we describe and characterize a small population of antibody-secreting class switched CD19+CD43+ B cells that lack expression of CD27 in the peripheral blood of healthy subjects. In this study, we characterized CD27-CD43+ cells. We demonstrate that class-switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphologically similar to antibody-secreting cells, show downregulation of B cell differentiation markers, and have a gene expression profile related to conventional plasmablasts. Despite these similarities, we observed differences in IgA and IgG subclass distribution, expression of homing markers, replication history, frequency of somatic hypermutation, immunoglobulin repertoire, gene expression related to Toll-like receptors, cytokines, and cytokine receptors, and antibody response to vaccination. Their frequency is altered in immune-mediated disorders.
- Published
- 2023
5. Presentation_1_Plasma cells are not restricted to the CD27+ phenotype: characterization of CD27-CD43+ antibody-secreting cells.pptx [Dataset]
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Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, Bossuyt, Xavier, Covens, Kris, Verbinnen, Bert, Jong, B. G. de, Moens, Leen, Wuyts, Greet, Verheyen, Geert, Nys, Kris, Cremer, Jonathan, Smulders, Stijn, Schrijvers, Rik, Weinhäusel, Andreas, Vermeire, Séverine, Verschueren, Patrick, Langhe, Ellen De, Dongen, J. J. M. van, Zelm, Menno C. van, and Bossuyt, Xavier
- Abstract
Circulating antibody-secreting cells are present in the peripheral blood of healthy individuals reflecting the continued activity of the humoral immune system. Antibody-secreting cells typically express CD27. Here we describe and characterize a small population of antibody-secreting class switched CD19+CD43+ B cells that lack expression of CD27 in the peripheral blood of healthy subjects. In this study, we characterized CD27-CD43+ cells. We demonstrate that class-switched CD27-CD43+ B cells possess characteristics of conventional plasmablasts as they spontaneously secrete antibodies, are morphologically similar to antibody-secreting cells, show downregulation of B cell differentiation markers, and have a gene expression profile related to conventional plasmablasts. Despite these similarities, we observed differences in IgA and IgG subclass distribution, expression of homing markers, replication history, frequency of somatic hypermutation, immunoglobulin repertoire, gene expression related to Toll-like receptors, cytokines, and cytokine receptors, and antibody response to vaccination. Their frequency is altered in immune-mediated disorders.
- Published
- 2023
6. Impact of T300A Variant of ATG16L1 on Antibacterial Response, Risk of Culture Positive Infections, and Clinical Course of Crohnʼs Disease
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Salem, Mohammad, Nielsen, Ole Haagen, Nys, Kris, Yazdanyar, Shiva, and Seidelin, Jakob Benedict
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- 2015
- Full Text
- View/download PDF
7. The major secreted protein Msp1/p75 is O-glycosylated in Lactobacillus rhamnosus GG
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Lebeer Sarah, Claes Ingmar JJ, Balog Crina IA, Schoofs Geert, Verhoeven Tine LA, Nys Kris, von Ossowski Ingemar, de Vos Willem M, Tytgat Hanne LP, Agostinis Patrizia, Palva Airi, Van Damme Els JM, Deelder André M, De Keersmaecker Sigrid CJ, Wuhrer Manfred, and Vanderleyden Jos
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Probiotic ,glycoprotein ,bacterial O-glycosylation ,Akt signaling ,peptidoglycan hydrolase ,Microbiology ,QR1-502 - Abstract
Abstract Background Although the occurrence, biosynthesis and possible functions of glycoproteins are increasingly documented for pathogens, glycoproteins are not yet widely described in probiotic bacteria. Nevertheless, knowledge of protein glycosylation holds important potential for better understanding specific glycan-mediated interactions of probiotics and for glycoengineering in food-grade microbes. Results Here, we provide evidence that the major secreted protein Msp1/p75 of the probiotic Lactobacillus rhamnosus GG is glycosylated. Msp1 was shown to stain positive with periodic-acid Schiff staining, to be susceptible to chemical deglycosylation, and to bind with the mannose-specific Concanavalin A (ConA) lectin. Recombinant expression in Escherichia coli resulted in a significant reduction in molecular mass, loss of ConA reactivity and increased sensitivity towards pronase E and proteinase K. Mass spectrometry showed that Msp1 is O-glycosylated and identified a glycopeptide TVETPSSA (amino acids 101-108) bearing hexoses presumably linked to the serine residues. Interestingly, these serine residues are not present in the homologous protein of several Lactobacillus casei strains tested, which also did not bind to ConA. The role of the glycan substitutions in known functions of Msp1 was also investigated. Glycosylation did not seem to impact significantly on the peptidoglycan hydrolase activity of Msp1. In addition, the glycan chain appeared not to be required for the activation of Akt signaling in intestinal epithelial cells by Msp1. On the other hand, examination of different cell extracts showed that Msp1 is a glycosylated protein in the supernatant, but not in the cell wall and cytosol fraction, suggesting a link between glycosylation and secretion of this protein. Conclusions In this study we have provided the first evidence of protein O-glycosylation in the probiotic L rhamnosus GG. The major secreted protein Msp1 is glycosylated with ConA reactive sugars at the serine residues at 106 and 107. Glycosylation is not required for the peptidoglycan hydrolase activity of Msp1 nor for Akt activation capacity in epithelial cells, but appears to be important for its stability and protection against proteases.
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- 2012
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8. Sustained SREBP-1-dependent lipogenesis as a key mediator of resistance to BRAF-targeted therapy
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Talebi, Ali, primary, Dehairs, Jonas, additional, Rambow, Florian, additional, Rogiers, Aljosja, additional, Nittner, David, additional, Derua, Rita, additional, Vanderhoydonc, Frank, additional, Duarte, Joao A. G., additional, Bosisio, Francesca, additional, Van den Eynde, Kathleen, additional, Nys, Kris, additional, Pérez, Mónica Vara, additional, Agostinis, Patrizia, additional, Waelkens, Etienne, additional, Van den Oord, Joost, additional, Fendt, Sarah-Maria, additional, Marine, Jean-Christophe, additional, and Swinnen, Johannes V., additional
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- 2018
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9. Genetic Defects in ER Stress and Autophagy Translate Into Increased Functional ER Stress Levels in Patients with Inflammatory Bowel Disease
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Vanhove, Wiebe, primary, Nys, Kris, additional, Arijs, Ingrid, additional, Cleynen, Isabelle, additional, de Bruyn, Magali, additional, Korf, Hannelie, additional, Ferrante, Marc, additional, Van Assche, Gert A., additional, and Vermeire, Severine, additional
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- 2017
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10. Su1909 Genetic Risk for Crohn's Disease has Little Impact on Intestinal Microbiota Composition
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Sabino, João, primary, Vieira-Silva, Sara, additional, Cleynen, Isabelle, additional, Nys, Kris, additional, Machiels, Kathleen, additional, Joossens, Marie, additional, Falony, Gwen, additional, Wang, Jun, additional, Ballet, Vera, additional, Ferrante, Marc, additional, Van Assche, Gert, additional, Van Der Merwe, Schalk, additional, Raes, Jeroen, additional, and Vermeire, Severine, additional
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- 2016
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11. Sa1821 Functional Translation of IBD-Associated Genetic Variation in Patient-Derived Intestinal Epithelial Cells
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Vanhove, Wiebe, primary, Nys, Kris, additional, Arijs, Ingrid, additional, Cleynen, Isabelle, additional, Van Assche, Gert, additional, Ferrante, Marc, additional, and Vermeire, Severine, additional
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- 2016
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12. ATG16L1:A multifunctional susceptibility factor in Crohn disease
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Salem, Mohammad, Ammitzboell, Mette, Nys, Kris, Seidelin, Jakob Benedict, Nielsen, Ole Haagen, Salem, Mohammad, Ammitzboell, Mette, Nys, Kris, Seidelin, Jakob Benedict, and Nielsen, Ole Haagen
- Abstract
Genetic variations in the autophagic pathway influence genetic predispositions to Crohn disease. Autophagy, the major lysosomal pathway for degrading and recycling cytoplasmic material, constitutes an important homeostatic cellular process. Of interest, single-nucleotide polymorphisms in ATG16L1 (autophagy-related 16-like 1 [S. cerevisiae]), a key component in the autophagic response to invading pathogens, have been associated with an increased risk of developing Crohn disease. The most common and well-studied genetic variant of ATG16L1 (rs2241880; leading to a T300A conversion) exhibits a strong association with risk for developing Crohn disease. The rs2241880 variant plays a crucial role in pathogen clearance, resulting in imbalanced cytokine production, and is linked to other biological processes, such as the endoplasmic reticulum stress/unfolded protein response. In this review, we focus on the importance of ATG16L1 and its genetic variant (T300A) within the elementary biological processes linked to Crohn disease., Genetic variations in the autophagic pathway influence genetic predispositions to Crohn disease. Autophagy, the major lysosomal pathway for degrading and recycling cytoplasmic material, constitutes an important homeostatic cellular process. Of interest, single-nucleotide polymorphisms in ATG16L1 (autophagy-related 16-like 1 [S. cerevisiae]), a key component in the autophagic response to invading pathogens, have been associated with an increased risk of developing Crohn disease. The most common and well-studied genetic variant of ATG16L1 (rs2241880; leading to a T300A conversion) exhibits a strong association with risk for developing Crohn disease. The rs2241880 variant plays a crucial role in pathogen clearance, resulting in imbalanced cytokine production, and is linked to other biological processes, such as the endoplasmic reticulum stress/unfolded protein response. In this review, we focus on the importance of ATG16L1 and its genetic variant (T300A) within the elementary biological processes linked to Crohn disease.
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- 2015
13. ATG16L1: A multifunctional susceptibility factor in Crohn disease
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Salem, Mohammad, primary, Ammitzboell, Mette, additional, Nys, Kris, additional, Seidelin, Jakob Benedict, additional, and Nielsen, Ole Haagen, additional
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- 2015
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14. Tu1770 - Genetic Defects in ER Stress and Autophagy Translate Into Increased Functional ER Stress Levels in Patients with Inflammatory Bowel Disease
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Vanhove, Wiebe, Nys, Kris, Arijs, Ingrid, Cleynen, Isabelle, de Bruyn, Magali, Korf, Hannelie, Ferrante, Marc, Van Assche, Gert A., and Vermeire, Severine
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- 2017
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15. Tumor Vessel Normalization by Chloroquine Independent of Autophagy
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Maes, Hannelore, primary, Kuchnio, Anna, additional, Peric, Aleksandar, additional, Moens, Stijn, additional, Nys, Kris, additional, De Bock, Katrien, additional, Quaegebeur, Annelies, additional, Schoors, Sandra, additional, Georgiadou, Maria, additional, Wouters, Jasper, additional, Vinckier, Stefan, additional, Vankelecom, Hugo, additional, Garmyn, Marjan, additional, Vion, Anne-Clémence, additional, Radtke, Freddy, additional, Boulanger, Chantal, additional, Gerhardt, Holger, additional, Dejana, Elisabetta, additional, Dewerchin, Mieke, additional, Ghesquière, Bart, additional, Annaert, Wim, additional, Agostinis, Patrizia, additional, and Carmeliet, Peter, additional
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- 2014
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16. Mo1719 Strong Mucosal Upregulation of AIM2 and IFI16 Inflammasomes in Patients With Active Inflammatory Bowel Disease
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Vanhove, Wiebe, primary, Staelens, Dominiek, additional, Peeters, Paul, additional, van der Goten, Jan, additional, De Schepper, Sebastiaan, additional, Cleynen, Isabelle, additional, Wouters, Emiel F., additional, Van Assche, Gert A., additional, Ferrante, Marc, additional, Vermeire, Severine, additional, Rutgeerts, Paul J., additional, Nys, Kris, additional, and Arij, Ingrid, additional
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- 2014
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17. 124a ER Stress and Autophagy-Related Susceptibility Loci Translate Into a Measurable Functional Response in Crohn's Patients: A Potential Tool for Personalized Medicine
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Nys, Kris, primary, Vanhove, Wiebe, additional, Cleynen, Isabelle, additional, Ferrante, Marc, additional, Van Assche, Gert A., additional, Rutgeerts, Paul J., additional, Agostinis, Patrizia, additional, and Vermeire, Severine, additional
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- 2014
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18. Genetic association and functional role of Crohn disease risk alleles involved in microbial sensing, autophagy, and endoplasmic reticulum (ER) stress
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Hoefkens, Eveline, primary, Nys, Kris, additional, John, Jestinah M, additional, Van Steen, Kristel, additional, Arijs, Ingrid, additional, Van der Goten, Jan, additional, Van Assche, Gert, additional, Agostinis, Patrizia, additional, Rutgeerts, Paul, additional, Vermeire, Séverine, additional, and Cleynen, Isabelle, additional
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- 2013
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19. The major secreted protein Msp1/p75 is O-glycosylated in Lactobacillus rhamnosus GG
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University of Helsinki, Faculty of Veterinary Medicine, Lebeer, Sarah, Claes, Ingmar J. J., Balog, Crina I. A., Schoofs, Geert, Verhoeven, Tine L. A., Nys, Kris, von Ossowski, Ingemar, de Vos, Willem M., Tytgat, Hanne L. P., Agostinis, Patrizia, Palva, Airi, Van Damme, Els J. M., Deelder, Andre M., De Keersmaecker, Sigrid C. J., Wuhrer, Manfred, Vanderleyden, Jos, University of Helsinki, Faculty of Veterinary Medicine, Lebeer, Sarah, Claes, Ingmar J. J., Balog, Crina I. A., Schoofs, Geert, Verhoeven, Tine L. A., Nys, Kris, von Ossowski, Ingemar, de Vos, Willem M., Tytgat, Hanne L. P., Agostinis, Patrizia, Palva, Airi, Van Damme, Els J. M., Deelder, Andre M., De Keersmaecker, Sigrid C. J., Wuhrer, Manfred, and Vanderleyden, Jos
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- 2012
20. A p38MAPK/HIF-1 Pathway Initiated by UVB Irradiation Is Required to Induce Noxa and Apoptosis of Human Keratinocytes
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Nys, Kris, primary, Van Laethem, An, additional, Michiels, Carine, additional, Rubio, Noemi, additional, Piette, Jacques G., additional, Garmyn, Maria, additional, and Agostinis, Patrizia, additional
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- 2010
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21. A p38MAPK/HIF-1 Pathway Initiated by UVB Irradiation Is Required to Induce Noxa and Apoptosis of Human Keratinocytes.
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Nys, Kris, Van Laethem, An, Michiels, Carine, Rubio, Noemi, Piette, Jacques G, Garmyn, Maria, and Agostinis, Patrizia
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APOPTOSIS , *KERATINOCYTES , *ULTRAVIOLET radiation , *MYELOID leukemia , *MITOCHONDRIA , *CELL death - Abstract
The signal transduction pathways leading to apoptosis of human keratinocytes responding to UVB irradiation are complex and not completely understood. Previously, we reported that in UVB-irradiated keratinocytes, p38MAPK instigates Bcl-2-associated X protein (Bax) activation and mitochondrial apoptosis. However, the molecular mechanism underlying the pro-apoptotic function of p38MAPK remained unclear. Here, we show that in UVB-treated human primary keratinocytes the activation of p38MAPK is necessary to upregulate Noxa, a BH3-only pro-apoptotic dominantly induced by UVB and required for apoptosis. Whereas p53-silencing was marginally cytoprotective and poorly affected Noxa expression, p38MAPK inhibition in p53-silenced keratinocytes or in p53−/− cells could still efficiently prevent Noxa induction and intrinsic apoptosis after UVB, indicating that p38MAPK signals mainly through p53-independent mechanisms. Furthermore, p38MAPK was required for the induction and activation of hypoxia-inducible factor 1 (HIF-1) in response to UVB, and HIF-1 knockdown reduced Noxa expression and apoptosis. In UVB-irradiated keratinocytes, Noxa targeted the anti-apoptotic myeloid cell leukemia sequence 1 (Mcl-1) for degradation, and small-interfering RNA (siRNA)-mediated knockdown of Noxa or p38MAPK inhibition restored levels of Mcl-1 and abolished apoptosis. Thus, the pro-apoptotic mechanisms orchestrated by p38MAPK in human keratinocytes in response to UVB involve an HIF-1/Noxa axis, which prompts the downregulation of anti-apoptotic Mcl-1, thereby favoring Bax-mediated mitochondrial apoptosis of UVB-damaged keratinocytes. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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22. Molecular characterization of pathophysiologic pathways in IBD and its therapeutic potential : Moleculaire karakterisatie van pathofysiologische processen in IBD en hun therapeutisch potentieel
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Vanhove, Wiebe, Arijs, Ingrid, Nys, Kris, and Vermeire, Séverine
- Subjects
IBD - Abstract
Inflammatory bowel diseases (IBD), with Crohn’s disease (CD) and ulcerative colitis (UC) as the two most prevalent phenotypes, span a disease spectrum of lifelong, idiopathic conditions characterized by chronic inflammation of the gut with diarrhea and abdominal pain. Although its exact pathophysiology remains elusive, IBD is believed to be caused by an aberrant mucosal immune responses towards intestinal microorganisms in genetically predisposed individuals. During the last years, new pathophysiologic pathways have been uncovered and since there still is an unmet therapeutic need in IBD, this knowledge is currently being applied by pharmaceutical companies to develop compounds that target these pathways. Therefore, in the first part of this project we aimed to contribute to the therapeutic development for IBD patients by performing a preclinical efficacy experiment in mice for a new experimental JAK1-specific inhibitor (GLPG0634/filgotinib) that has been developed by Galapagos NV. Since the efficacy of filgotinib was already shown in a chemically induced murine colitis model (DSS), we performed these experiments in the T cell transfer model of colitis which is an adaptive/T cell-driven model. Daily oral administration of filgotinib resulted in a significant reduction in body weight loss and histological inflammation scores. Our data, together with the data obtained from the chronic DSS model, provide convincing preclinical evidence for the application of filgotinib in IBD and meanwhile a large phase 3 program is ongoing. Other new therapeutic strategies, are in the research pipeline or reaching registration. This means that, in the future, the range of therapies will drastically expand. Furthermore, a well-known characteristic of IBD is the large inter-patient variability in disease course and severity, which has consequences for the type, the dose and frequency of treatment. We believe that the IBD treatment paradigm should change towards a more personalized approach that is based on targeting the underlying pathophysiologic pathways that drive the disease in a given patient. The second part of this PhD project investigated the contribution of three IBD-associated pathways (ER stress, autophagy and inflammasomes) in specific patient-subgroups at different levels. First of all, we developed a novel cell culture system that allows short term expansion of patient/biopsy-derived intestinal epithelial monolayers. We confirmed that these monolayers had an epithelial character and a normal apical-basolateral polarization. In this model we showed that the number of risk alleles in ER stress and/or autophagy leads to an increased BIP induction after thapsigargin treatment indicating functional alterations in the epithelial ER stress response. These readouts might in the future be used as an indication for ER stress reducing therapies such as TUDCA. Furthermore, we believe that this patient-derived intestinal epithelial cell culture approach has more potential applications such as co-culturing with other cell types and/or investigating patient-specific responses to pharmaceuticals or even microbes. Finally, we investigated the inflammasome, ER stress and autophagy at a transcriptional level in the mucosa of patients and healthy controls who were included in two well-characterized whole genome gene expression microarray cohorts. We found a strong upregulation of two dsDNA-responsive inflammasome sensors AIM2 and IFI16 in patients with active disease when compared to patients with inactive disease or healthy controls. We are one of the first groups to identify the potential involvement of both inflammasome sensors which are now subject of investigation as a disease activity marker (IFI16) and a key player in intestinal homeostasis (AIM2). We also found a strong upregulation of several ER stress genes and a downregulation of autophagy genes that was associated with increased disease activity. When disease was controlled normalization was observed for most of these genes, yet some (KDELR3, XBP1, MAP1LC3A and CHMP4B) remained dysregulated, indicating that these pathways are not entirely restored to their normal levels upon remission. Finally, we found a gene expression signature in these pathways that could aid in predicting the response to anti-TNF treatment caused by an altered ER stress or autophagy status. Although preliminary, these data hint towards the application of ER stress reducing or autophagy stimulating therapy in patients who show, already at baseline, dysregulated gene expression patterns. In conclusion, the promising filgotinib data demonstrate that we live in a time of increasing therapeutic diversity for IBD. In this PhD thesis we furthermore set the first steps towards a personalized pathway-based approach for treating this multifactorial disease spectrum. LIST OF ABBREVIATIONS 8 CHAPTER 1 INTRODUCTION 13 1. The paradigm of patient management in IBD 15 2. Toward innovative management of IBD 17 2.1. Anti-IL-12/23 17 2.2. Janus kinases inhibition 18 2.3. Leukocyte trafficking 20 3. Targeting early events in IBD pathogenesis to restore intestinal homeostasis 21 3.1. Anti-Smad7 (TGF-β/BMP signaling) and other antisense oligonucleotides 21 3.2. Cell-based therapies 24 4. Future prospects in IBD management 26 4.1. A mechanism-based approach 26 4.2. Toward personalized IBD management 31 5. Conclusion 33 6. References 35 CHAPTER 2 RESEARCH OBJECTIVES 43 PART I IN VIVO TARGETING OF THE JAK-STAT PATHWAY IN IBD 47 CHAPTER 3 SELECTIVE INHIBITION OF JANUS KINASE 1 (JAK1) WITH FILGOTINIB REVERSES PATHOGENIC PROCESSES IN PRECLINICAL MODELS FOR IBD 49 1. Introduction 52 2. Materials and Methods 54 2.1. Reagents 54 2.2. Mice 54 2.3. Induction of chronic colitis and Experimental setup 54 2.4. Monitoring of disease 54 2.5. Statistical analysis 56 3. Results 57 3.1. Pilot experiments 57 3.2. Filgotinib reduces body weight loss and inflammatory scores 59 4. Discussion 61 5. References 64 PART II FUNCTIONAL TRANSLATION OF IDENTIFIED PATHWAYS IN IBD 67 CHAPTER 4 BIOPSY-DERIVED INTESTINAL EPITHELIAL CELL CULTURES FOR PATHWAY BASED STRATIFICATION OF PATIENTS WITH INFLAMMATORY BOWEL DISEASE 69 1. Abstract 71 2. Introduction 72 3. Materials and methods 74 3.1. Patients and ethical statement 74 3.2. Isolation and culturing of IECs 75 3.3. Immunocytochemistry 76 3.4. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis 77 3.5. ER stress induction 78 3.6. Binding immunoglobulin protein (BiP)/Glucose-regulated protein 78 (GRP78) ELISA 78 3.7. Statistical analysis 78 4. Results 79 4.1. IECs and epithelial characterization 79 4.2. Genetic risk in ER stress and autophagy genes and the epithelial ER stress response 82 5. Discussion 86 6. Supplementary material 90 7. References 92 CHAPTER 5 STRONG UPREGULATION OF AIM2 AND IFI16 INFLAMMASOMES IN THE MUCOSA OF PATIENTS WITH ACTIVE INFLAMMATORY BOWEL DISEASE 95 1. Abstract 97 2. Introduction 98 3. Materials and methods 100 3.1. Patients and biopsy specimens 100 3.2. Mucosal gene expression analysis 100 3.3. RNA isolation 100 3.4. Whole-genome gene expression analysis 101 3.5. qRT-PCR analysis 101 3.6. Immunohistochemistry 102 3.7. Western blot analysis 102 3.8. Ethical considerations 102 4. Results 103 4.1. Gene expression of different inflammasome subtypes in IBD colonic mucosa 103 4.2. Validation of AIM2 and IFI16 expression at the protein level 107 4.3. Immunohistochemistry 108 5. Discussion 111 6. Supplementary material 115 6.1. Protocol details 115 6.2. Supplementary tables 117 6.3. Supplementary figures 118 7. References 120 CHAPTER 6 MUCOSAL EXPRESSION OF AUTOPHAGY AND ER STRESS GENES IN INFLAMMATORY BOWEL DISEASES 125 1. Introduction and aim 127 2. Material and methods 128 2.1. Selection of ER stress and autophagy associated genes 128 3. Results 129 3.1. ER stress genes 129 3.2. Autophagy genes 134 4. Discussion 137 5. Supplementary material 142 5.1. Filtering of ER stress genes 142 5.2. Filtering of autophagy genes 142 5.3. Supplementary tables 143 6. References 144 CHAPTER 7 CONCLUDING DISCUSSION 149 1. General discussion 151 2. Future perspectives 159 3. References 162 SUMMARIES 167 1. English summary 167 2. Nederlandstalige samenvatting 169 3. Popular summary 171 4. Popular summary (Dutch) 173 SCIENTIFIC ACKNOWLEDGEMENTS 175 PERSONAL CONTRIBUTION 176 CONFLICTS OF INTEREST STATEMENT 177 ACKNOWLEDGEMENTS - DANKWOORD 178 CURRICULUM VITAE 190 SCIENTIFIC COMMUNICATIONS 192 nrpages: 194 status: published
- Published
- 2017
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