Cytométrie Paris

Publications

Année de publication : 2018

Marina Wierz, Sandrine Pierson, Léa Guyonnet, Elodie Viry, Audrey Lequeux, Anaïs Oudin, Simone P Niclou, Markus Ollert, Guy Berchem, Bassam Janji, Coralie Guérin, Jerome Paggetti, Etienne Moussay (2018 Feb 15)

Dual PD1/LAG3 immune checkpoint blockade limits tumor development in a murine model of chronic lymphocytic leukemia.

Blood : 1617-1621 : DOI : 10.1182/blood-2017-06-792267 En savoir plus
Résumé

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Lynda Zeboudj, Mikael Maître, Lea Guyonnet, Ludivine Laurans, Jeremie Joffre, Jeremie Lemarie, Simon Bourcier, Wared Nour-Eldine, Coralie Guérin, Jonas Friard, Abdelilah Wakkach, Elizabeth Fabre, Alain Tedgui, Ziad Mallat, Pierre-Louis Tharaux, Hafid Ait-Oufella (2018 Jan 13)

Selective EGF-Receptor Inhibition in CD4 T Cells Induces Anergy and Limits Atherosclerosis.

Journal of the American College of Cardiology : 160-172 : DOI : S0735-1097(17)41588-9 En savoir plus
Résumé

Several epidermal growth factor receptor (EGFR) inhibitors have been successfully developed for the treatment of cancer, limiting tumor growth and metastasis. EGFR is also expressed by leukocytes, but little is known about its role in the modulation of the immune response.

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Année de publication : 2017

Lynda Zeboudj, Andréas Giraud, Lea Guyonnet, Yujiao Zhang, Ludivine Laurans, Bruno Esposito, Jose Vilar, Anna Chipont, Nikolina Papac-Milicevic, Christoph J Binder, Alain Tedgui, Ziad Mallat, Pierre-Louis Tharaux, Hafid Ait-Oufella (2017 Dec 2)

Selective EGFR (Epidermal Growth Factor Receptor) Deletion in Myeloid Cells Limits Atherosclerosis-Brief Report.

Arteriosclerosis, thrombosis, and vascular biology : 114-119 : DOI : 10.1161/ATVBAHA.117.309927 En savoir plus
Résumé

To determine the consequences of specific inhibition of EGFR (epidermal growth factor receptor) in myeloid cells in atherosclerosis development.

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Nour C Bacha, Adeline Blandinieres, Elisa Rossi, Nicolas Gendron, Nathalie Nevo, Séverine Lecourt, Coralie L Guerin, Jean Marie Renard, Pascale Gaussem, Eduardo Angles-Cano, Chantal M Boulanger, Dominique Israel-Biet, David M Smadja (2017 Nov 5)

Endothelial Microparticles are Associated to Pathogenesis of Idiopathic Pulmonary Fibrosis.

Stem cell reviews and reports : 223-235 : DOI : 10.1007/s12015-017-9778-5 En savoir plus
Résumé

Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by obliteration of alveolar architecture, resulting in declining lung function and ultimately death. Pathogenic mechanisms remain unclear but involve a concomitant accumulation of scar tissue together with myofibroblasts activation. Microparticles (MPs) have been investigated in several human lung diseases as possible pathogenic elements, prognosis markers and therapeutic targets. We postulated that levels and cellular origins of circulating MPs might serve as biomarkers in IPF patients and/or as active players of fibrogenesis. Flow cytometry analysis showed a higher level of Annexin-V positive endothelial and platelet MPs in 41 IPF patients compared to 22 healthy volunteers. Moreover, in IPF patients with a low diffusing capacity of the lung for carbon monoxide (DL<40%), endothelial MPs (EMPs) were found significantly higher compared to those with DL>40% (p = 0.02). We then used EMPs isolated from endothelial progenitor cells (ECFCs) extracted from IPF patients or controls to modulate normal human lung fibroblast (NHLF) properties. We showed that EMPs did not modify proliferation, collagen deposition and myofibroblast transdifferentiation. However, EMPs from IPF patients stimulated migration capacity of NHLF. We hypothesized that this effect could result from EMPs fibrinolytic properties and found indeed higher plasminogen activation potential in total circulating MPs and ECFCs derived MPs issued from IPF patients compared to those isolated from healthy controls MPs. Our study showed that IPF is associated with an increased level of EMPs in the most severe patients, highlighting an active process of endothelial activation in the latter. Endothelial microparticles might contribute to the lung fibroblast invasion mediated, at least in part, by a fibrinolytic activity.

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Takouhie Mgrditchian, Tsolere Arakelian, Jérôme Paggetti, Muhammad Zaeem Noman, Elodie Viry, Etienne Moussay, Kris Van Moer, Stephanie Kreis, Coralie Guerin, Stephanie Buart, Caroline Robert, Christophe Borg, Philippe Vielh, Salem Chouaib, Guy Berchem, Bassam Janji (2017 Oct 29)

Targeting autophagy inhibits melanoma growth by enhancing NK cells infiltration in a CCL5-dependent manner.

Proceedings of the National Academy of Sciences of the United States of America : E9271-E9279 : DOI : 10.1073/pnas.1703921114 En savoir plus
Résumé

While blocking tumor growth by targeting autophagy is well established, its role on the infiltration of natural killer (NK) cells into tumors remains unknown. Here, we investigate the impact of targeting autophagy gene Beclin1 () on the infiltration of NK cells into melanomas. We show that, in addition to inhibiting tumor growth, targeting increased the infiltration of functional NK cells into melanoma tumors. We provide evidence that driving NK cells to the tumor bed relied on the ability of autophagy-defective tumors to transcriptionally overexpress the chemokine gene Such infiltration and tumor regression were abrogated by silencing CCL5 in BECN1-defective tumors. Mechanistically, we show that the up-regulated expression of CCL5 occurred through the activation of its transcription factor c-Jun by a mechanism involving the impairment of phosphatase PP2A catalytic activity and the subsequent activation of JNK. Similar to , targeting other autophagy genes, such as , /, or inhibiting autophagy pharmacologically by chloroquine, also induced the expression of in melanoma cells. Clinically, a positive correlation between CCL5 and NK cell marker NKp46 expression was found in melanoma patients, and a high expression level of CCL5 was correlated with a significant improvement of melanoma patients’ survival. We believe that this study highlights the impact of targeting autophagy on the tumor infiltration by NK cells and its benefit as a novel therapeutic approach to improve NK-based immunotherapy.

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Clément d'Audigier, Sophie Susen, Adeline Blandinieres, Virginie Mattot, Bruno Saubamea, Elisa Rossi, Nathalie Nevo, Séverine Lecourt, Coralie L Guerin, Blandine Dizier, Nicolas Gendron, Bertrand Caetano, Pascale Gaussem, Fabrice Soncin, David M Smadja (2017 Oct 6)

Egfl7 Represses the Vasculogenic Potential of Human Endothelial Progenitor Cells.

Stem cell reviews and reports : 82-91 : DOI : 10.1007/s12015-017-9775-8 En savoir plus
Résumé

Egfl7 (VE-statin) is a secreted protein mostly specific to the endothelial lineage during development and in the adult and which expression is enhanced during angiogenesis. Egfl7 involvement in human postnatal vasculogenesis remains unresolved yet. Our aim was to assess Egfl7 expression in several angiogenic cell types originating from human bone marrow, peripheral blood, or cord blood. We found that only endothelial colony forming cells (ECFC), which are currently considered as the genuine endothelial precursor cells, expressed large amounts of Egfl7. In order to assess its potential roles in ECFC, Egfl7 was repressed in ECFC by RNA interference and ECFC angiogenic capacities were tested in vitro and in vivo. Cell proliferation, differentiation, and migration were significantly improved when Egfl7 was repressed in ECFC in vitro, whereas miR-126-3p levels remained unchanged. In vivo, repression of Egfl7 in ECFC significantly improved post-ischemic revascularization in a model of mouse hind-limb ischemia. In conclusion, ECFC are the sole postnatal angiogenic cells which express large amounts of Egfl7 and whose angiogenic properties are repressed by this factor. Thus, Egfl7 inhibition may be considered as a therapeutic option to improve ECFC-mediated postnatal vasculogenesis and to optimize in vitro ECFC expansion in order to develop an optimized cell therapy approach.

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Elisa Rossi, David Smadja, Celine Goyard, Audrey Cras, Blandine Dizier, Nour Bacha, Anna Lokajczyk, Coralie L Guerin, Nicolas Gendron, Benjamin Planquette, Virginie Mignon, Carmelo Bernabéu, Olivier Sanchez, David M Smadja (2017 Aug 4)

Co-injection of mesenchymal stem cells with endothelial progenitor cells accelerates muscle recovery in hind limb ischemia through an endoglin-dependent mechanism.

Thrombosis and haemostasis : 1908-1918 : DOI : 10.1160/TH17-01-0007 En savoir plus
Résumé

Endothelial colony-forming cells (ECFCs) are progenitor cells committed to endothelial lineages and have robust vasculogenic properties. Mesenchymal stem cells (MSCs) have been described to support ECFC-mediated angiogenic processes in various matrices. However, MSC-ECFC interactions in hind limb ischemia (HLI) are largely unknown. Here we examined whether co-administration of ECFCs and MSCs bolsters vasculogenic activity in nude mice with HLI. In addition, as we have previously shown that endoglin is a key adhesion molecule, we evaluated its involvement in ECFC/MSC interaction. Foot perfusion increased on day 7 after ECFC injection and was even better at 14 days. Co-administration of MSCs significantly increased vessel density and foot perfusion on day 7 but the differences were no longer significant at day 14. Analysis of mouse and human CD31, and in situ hybridization of the human ALU sequence, showed enhanced capillary density in ECFC+MSC mice. When ECFCs were silenced for endoglin, coinjection with MSCs led to lower vessel density and foot perfusion at both 7 and 14 days (p<0.001). Endoglin silencing in ECFCs did not affect MSC differentiation into perivascular cells or other mesenchymal lineages. Endoglin silencing markedly inhibited ECFC adhesion to MSCs. Thus, MSCs, when combined with ECFCs, accelerate muscle recovery in a mouse model of hind limb ischemia, through an endoglin-dependent mechanism.

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Zofia Maciorowski, Pratip K Chattopadhyay, Paresh Jain (2017 Apr 4)

Basic Multicolor Flow Cytometry.

Current protocols in immunology : 5.4.1-5.4.38 : DOI : 10.1002/cpim.26 En savoir plus
Résumé

Multicolor flow cytometry is a rapidly evolving technology that uses multiple fluorescent markers to identify and characterize cellular subpopulations of interest, allowing rapid analysis on tens of thousands of cells per second, with the possibility of isolating pure, viable populations by cell sorting for further experimentation. This unit covers the tools needed by the beginning immunologist to plan and run multicolor experiments, with information on fluorochromes and their characteristics, spectral spillover, compensation and spread, instrument and reagent variables, and the basic elements of multicolor panel design. Protocols to quantify and maximize sensitivity by titration of reagents and optimization of instrument settings, as well as basic surface and intracellular cell staining, are included. © 2017 by John Wiley & Sons, Inc.

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Coralie L Guerin, Elisa Rossi, Bruno Saubamea, Audrey Cras, Virginie Mignon, Jean-Sébastien Silvestre, David M Smadja (2017 Mar 18)

Human very Small Embryonic-like Cells Support Vascular Maturation and Therapeutic Revascularization Induced by Endothelial Progenitor Cells.

Stem cell reviews and reports : 552-560 : DOI : 10.1007/s12015-017-9731-7 En savoir plus
Résumé

Very small embryonic-like stem cells (VSELs) are major pluripotent stem cells defined as cells of small size being Lineage- negative, CD133-positive, and CD45-negative. We previously described that human bone marrow VSELs were able to differentiate into endothelial cells and promoted post-ischemic revascularization in mice with surgically induced critical limb ischemia. In the present work, we isolated bone marrow VSELs from patients with critical limb ischemia and studied their ability to support endothelial progenitor cells therapeutic capacity and revascularization potential. Sorted bone marrow VSELs cultured in angiogenic media were co-injected with endothelial progenitor cells and have been show to trigger post-ischemic revascularization in immunodeficient mice, and support vessel formation in vivo in Matrigel implants better than human bone marrow mesenchymal stem cells. In conclusion, VSELs are a potential new source of therapeutic cells that may give rise to cells of the endothelial and perivascular lineage in humans. VSELs are the first real vasculogenic stem cells able to differentiate in endothelial and perivascular lineage in human adult described from now. Thus, because VSELs presence have been proposed in adult tissues, we think that VSELs are CD45 negative stem cells able to give rise to vascular regeneration in human tissues and vessels.

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Coralie L Guerin, Adeline Blandinières, Benjamin Planquette, Jean-Sébastien Silvestre, Dominique Israel-Biet, Olivier Sanchez, David M Smadja (2017 Mar 13)

Very Small Embryonic-like Stem Cells Are Mobilized in Human Peripheral Blood during Hypoxemic COPD Exacerbations and Pulmonary Hypertension.

Stem cell reviews and reports : 561-566 : DOI : 10.1007/s12015-017-9732-6 En savoir plus
Résumé

Very small embryonic-like stem cells (VSELs) are major pluripotent stem cells involved in vascular and tissue regeneration and constitute a recruitable pool of stem/progenitor cells with putative instrumental role in organ repair. Here, we hypothesized that VSELs might be mobilized from the bone marrow (BM) to peripheral blood (PB) in patients with hypoxic lung disease or pulmonary hypertension (PH). The objective of the present study was then to investigate the changes in VSELs number in peripheral blood of patients with hypoxic lung disease and PH. We enrolled 26 patients with Chronic Obstructive Pulmonary Disease (COPD) with or without hypoxemia, 13 patients with PH and 20 controls without any respiratory or cardiovascular diseases. In PH patients, VSELs levels have been determined during right heart catheterization in pulmonary blood and PB. For this purpose, mononuclear cells were separated by density gradient and VSELs have been quantified by using a multiparametric flow cytometry approach. The number of PB-VSELs in hypoxic COPD patients was significantly increased compared with non-hypoxic COPD patients or controls (p = 0.0055). In patients with PH, we did not find any difference in VSELs numbers between arterial pulmonary blood and venous PB (p = 0.93). However, we found an increase in VSELs in the peripheral blood of patients with PH (p = 0.03). In conclusion, we unraveled that circulating VSELs were increased in peripheral blood of patients with hypoxic COPD or with PH. Thus, VSELs may serve as a reservoir of pluripotent stem cells that can be recruited into PB and may play an important role in promoting lung repair.

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Eléonore Blondiaux, Laetitia Pidial, Gwennhael Autret, Gabriel Rahmi, Daniel Balvay, Etienne Audureau, Claire Wilhelm, Coralie L Guerin, Patrick Bruneval, Jean-Sébastien Silvestre, Philippe Menasché, Olivier Clément (2017 Feb 4)

Bone marrow-derived mesenchymal stem cell-loaded fibrin patches act as a reservoir of paracrine factors in chronic myocardial infarction.

Journal of tissue engineering and regenerative medicine : 3417-3427 : DOI : 10.1002/term.2255 En savoir plus
Résumé

The combination of mesenchymal stem cells and tissue-engineered fibrin patches improves the therapeutic efficacy of stem cells. In vivo cardiac magnetic resonance (4.7 Tesla) and ex vivo high-spatial resolution CMR were used to track the fate of human bone marrow-derived mesenchymal stem cell (BMSC) delivered on an epicardial scaffold and more specifically assess their potential intramyocardial migration. Fifty-seven nude rats underwent permanent coronary artery ligation. Two months later, those with a left ventricular ejection fraction ≤55% were randomly allocated to receive a patch loaded with human BMSC (BMSC-P, n = 10), a patch loaded with BMSCs labelled with iron oxide nanoparticles (BMSC*-P, n = 12), an acellular patch (A-P, n = 8) or to serve as sham-operated animals (SHAM, n = 7). BMSC secretion of cytokines and growth factors was evaluated with flow-cytometry. Cardiac functional parameters of cell-treated groups (BMSC*-P and BMSC-P) yielded significantly better outcomes than the SHAM group (p = 0.044 and p = 0.026, respectively, for ejection fraction). Angiogenesis was higher in the cell-patch than in control groups (e.g. BMSC*P vs. SHAM: p = 0.007). No BMSCs were identified into the myocardium on cardiac magnetic resonance or histological sections, although persisting BMSCs were identified on the epicardial surface 21 days post-transplantation in 10% of rats hearts (Lamin A/C and CD90 positive). Cytokine and growth factor profiling demonstrated an increase in their release by cells seeded in patches. The absence of stem cell migration into the myocardium and the persistence of stem cells on the epicardial surface suggest that fibrin patches are likely to act predominantly as reservoirs of paracrine factors. Copyright © 2017 John Wiley & Sons, Ltd.

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