Mansouri, Ahmed

[["dc.bibliographiccitation.artnumber","e2622"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","PLoS ONE"],["dc.bibliographiccitation.volume","3"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Schindehuette, Jan"],["dc.contributor.author","Kuhlmann, Tanja"],["dc.contributor.author","Elsner, Leslie"],["dc.contributor.author","Novota, Peter"],["dc.contributor.author","Baier, Paul Christian"],["dc.contributor.author","Schillert, Arne"],["dc.contributor.author","Bickeboeller, Heike"],["dc.contributor.author","Herrmann, Thomas R."],["dc.contributor.author","Trenkwalder, Claudia"],["dc.contributor.author","Paulus, Walter J."],["dc.contributor.author","Mansouri, Ahmed"],["dc.date.accessioned","2018-11-07T11:13:02Z"],["dc.date.available","2018-11-07T11:13:02Z"],["dc.date.issued","2008"],["dc.description.abstract","Embryonic stem (ES) cells have the potential to differentiate into all cell types and are considered as a valuable source of cells for transplantation therapies. A critical issue, however, is the risk of teratoma formation after transplantation. The effect of the immune response on the tumorigenicity of transplanted cells is poorly understood. We have systematically compared the tumorigenicity of mouse ES cells and in vitro differentiated neuronal cells in various recipients. Subcutaneous injection of 1 x 10(6) ES or differentiated cells into syngeneic or allogeneic immunodeficient mice resulted in teratomas in about 95% of the recipients. Both cell types did not give rise to tumors in immunocompetent allogeneic mice or xenogeneic rats. However, in 61% of cyclosporine A-treated rats teratomas developed after injection of differentiated cells. Undifferentiated ES cells did not give rise to tumors in these rats. ES cells turned out to be highly susceptible to killing by rat natural killer (NK) cells due to the expression of ligands of the activating NK receptor NKG2D on ES cells. These ligands were downregulated on differentiated cells. The activity of NK cells which is not suppressed by cyclosporine A might contribute to the prevention of teratomas after injection of ES cells but not after inoculation of differentiated cells. These findings clearly point to the importance of the immune response in this process. Interestingly, the differentiated cells must contain a tumorigenic cell population that is not present among ES cells and which might be resistant to NK cell-mediated killing."],["dc.identifier.doi","10.1371/journal.pone.0002622"],["dc.identifier.isi","000264065800024"],["dc.identifier.pmid","18612432"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8264"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/53801"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Public Library Science"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 2.5"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.5"],["dc.title","The Tumorigenicity of Mouse Embryonic Stem Cells and In Vitro Differentiated Neuronal Cells Is Controlled by the Recipients' Immune Response"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","396"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Stem Cells"],["dc.bibliographiccitation.lastpage","404"],["dc.bibliographiccitation.volume","22"],["dc.contributor.author","Baier, Paul Christian"],["dc.contributor.author","Schindehutte, J."],["dc.contributor.author","Thinyane, K."],["dc.contributor.author","Flugge, G."],["dc.contributor.author","Fuchs, E."],["dc.contributor.author","Mansouri, Ahmed"],["dc.contributor.author","Paulus, Walter J."],["dc.contributor.author","Gruss, P."],["dc.contributor.author","Trenkwalder, Claudia"],["dc.date.accessioned","2018-11-07T10:53:15Z"],["dc.date.available","2018-11-07T10:53:15Z"],["dc.date.issued","2004"],["dc.description.abstract","Objective. Transplantation of fetal mesencephalic cells into the striatum has been performed in about 350 patients with Parkinson's disease and has been intensively studied in rat models of Parkinson's disease. Limited access to this material has shifted the focus toward embryonic stem (ES) cells. The grafting of undifferentiated ES cells to 6-hydroxy-dopamine (6-OHDA)-lesioned rats leads to behavioral improvements but may induce teratoma-like structures. This risk might be avoided by using more differentiated ES cells. In this study, we aimed to investigate differentiated mouse ES cells regarding their in vivo development and fate after transplantation in the striatum in the 6-OHDA rat model and the behavioral changes induced after transplantation. Methods. Mouse ES cells were differentiated on PA6 feeder cells for 14 days before grafting. Twenty to twenty-five percent of the neurons obtained were positive for tyrosine-hydroxylase (TH). PKH26-labeled cells were transplanted in the striata of unilaterally 6-OHDA-lesioned rats. Results. Direct PKH26 fluorescence visualization and TH staining proved the existence of cell deposits in the striata of all grafted animals, indicating cell survival for at least 5 weeks posttransplantation. There was no evidence of tumor formation. Immunocytochemical staining showed glial immunoreactivity surrounding the grafted cell deposits, probably inhibiting axonal outgrowth into the surrounding host tissue. There was a significant reduction in amphetamine-induced rotational behavior seen in grafted animals, which was not observed in sham-operated animals. Conclusions. The findings of this study suggest that the amphetamine-induced rotational behavioral test without histological confirmation is not proof of morphological integration with axonal outgrowth within the first 4 weeks posttransplantation."],["dc.identifier.doi","10.1634/stemcells.22-3-396"],["dc.identifier.isi","000221869600019"],["dc.identifier.pmid","15153616"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/49315"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","1066-5099"],["dc.title","Behavioral changes in unilaterally 6-hydroxy-dopamine lesioned rats after transplantation of differentiated mouse embryonic stem cells without morphological integration"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","IUBMB Life"],["dc.bibliographiccitation.volume","61"],["dc.contributor.author","Mansouri, Ahmed"],["dc.contributor.author","Kuhlmann, Tanja"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Trenkwalder, Claudia"],["dc.contributor.author","Paulus, Walter J."],["dc.date.accessioned","2018-11-07T08:32:13Z"],["dc.date.available","2018-11-07T08:32:13Z"],["dc.date.issued","2009"],["dc.format.extent","282"],["dc.identifier.isi","000264089500015"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/17287"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","John Wiley & Sons Inc"],["dc.publisher.place","Hoboken"],["dc.relation.issn","1521-6543"],["dc.title","EMBRYONIC STEM CELL-DERIVED DOPAMINERGIC NEURONS FOR THE THERAPY OF PARKINSON'S DISEASE"],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","248"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","World journal of stem cells"],["dc.bibliographiccitation.lastpage","255"],["dc.bibliographiccitation.volume","6"],["dc.contributor.author","Liao, Mei-Chih"],["dc.contributor.author","Diaconu, Mihaela"],["dc.contributor.author","Monecke, Sebastian"],["dc.contributor.author","Collombat, Patrick"],["dc.contributor.author","Timaeus, Charles"],["dc.contributor.author","Kuhlmann, Tanja"],["dc.contributor.author","Paulus, Walter"],["dc.contributor.author","Trenkwalder, Claudia"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Mansouri, Ahmed"],["dc.date.accessioned","2019-07-09T11:42:00Z"],["dc.date.available","2019-07-09T11:42:00Z"],["dc.date.issued","2014-04-26"],["dc.description.abstract","AIM: To find a safe source for dopaminergic neurons, we generated neural progenitor cell lines from human embryonic stem cells. METHODS: The human embryonic stem (hES) cell line H9 was used to generate human neural progenitor (HNP) cell lines. The resulting HNP cell lines were differentiated into dopaminergic neurons and analyzed by quantitative real-time polymerase chain reaction and immunofluorescence for the expression of neuronal differentiation markers, including beta-III tubulin (TUJ1) and tyrosine hydroxylase (TH). To assess the risk of teratoma or other tumor formation, HNP cell lines and mouse neuronal progenitor (MNP) cell lines were injected subcutaneously into immunodeficient SCID/beige mice. RESULTS: We developed a fairly simple and fast protocol to obtain HNP cell lines from hES cells. These cell lines, which can be stored in liquid nitrogen for several years, have the potential to differentiate in vitro into dopaminergic neurons. Following day 30 of differentiation culture, the majority of the cells analyzed expressed the neuronal marker TUJ1 and a high proportion of these cells were positive for TH, indicating differentiation into dopaminergic neurons. In contrast to H9 ES cells, the HNP cell lines did not form tumors in immunodeficient SCID/beige mice within 6 mo after subcutaneous injection. Similarly, no tumors developed after injection of MNP cells. Notably, mouse ES cells or neuronal cells directly differentiated from mouse ES cells formed teratomas in more than 90% of the recipients. CONCLUSION: Our findings indicate that neural progenitor cell lines can differentiate into dopaminergic neurons and bear no risk of generating teratomas or other tumors in immunodeficient mice."],["dc.identifier.doi","10.4252/wjsc.v6.i2.248"],["dc.identifier.fs","604380"],["dc.identifier.pmid","24772251"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/12652"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58563"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1948-0210"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Embryonic stem cell-derived neural progenitors as non-tumorigenic source for dopaminergic neurons."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","80"],["dc.bibliographiccitation.issue","1-2"],["dc.bibliographiccitation.journal","Brain Research"],["dc.bibliographiccitation.lastpage","87"],["dc.bibliographiccitation.volume","1045"],["dc.contributor.author","Thinyane, K."],["dc.contributor.author","Baier, Paul Christian"],["dc.contributor.author","Schindehutte, J."],["dc.contributor.author","Mansouri, Ahmed"],["dc.contributor.author","Paulus, Walter J."],["dc.contributor.author","Trenkwalder, Claudia"],["dc.contributor.author","Flugge, G."],["dc.contributor.author","Fuchs, E."],["dc.date.accessioned","2018-11-07T10:59:19Z"],["dc.date.available","2018-11-07T10:59:19Z"],["dc.date.issued","2005"],["dc.description.abstract","We transplanted mouse embryonic stem (ES) cells pre-differentiated on a PA6 feeder cell layer into the striatum of 6-hydroxydopamine hemi-lesioned adult rats and studied the fate of the grafted cells 1 and 5 weeks post-grafting. At both time points, ES cell grafts contained tyrosine hydroxylase positive (TH+) and 5-HT immunoreactive cells. Between 1 and 5 weeks, there was an enlargement of the grafts and an increase in number of TH+ cells although the differences between the two time points were not significant. The mean number of TH+ neurons per striatum was 330 73 after 1 week and 1220 400 after 5 weeks. Over the same time period, mean soma profile area of the TH+ neurons increased significantly by 25.2%. Neurites were longer after 5 weeks (by 24.9%), but the difference to 1 week post-grafting was not reliable. The percentage of TH+ somata without neurites increased from 6.7% after 1 week to 38.3% after 5 weeks (not significant). After 5 weeks, two out of fifteen graft recipients had tumors indicating that pre-differentiation of mouse embryonic stem cells using this differentiation protocol is not sufficient to prevent tumor formation. (C) 2005 Elsevier B.V. All rights reserved."],["dc.identifier.doi","10.1016/j.brainres.2005.03.033"],["dc.identifier.isi","000229530300010"],["dc.identifier.pmid","15910765"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/50671"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Bv"],["dc.relation.issn","0006-8993"],["dc.title","Fate of pre-differentiated mouse embryonic stem cells transplanted in unilaterally 6-hydroxydopamine lesioned rats: Histological characterization of the grafted cells"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","870"],["dc.bibliographiccitation.journal","Frontiers in Immunology"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Gröschel, Carina"],["dc.contributor.author","Hübscher, Daniela"],["dc.contributor.author","Nolte, Jessica"],["dc.contributor.author","Monecke, Sebastian"],["dc.contributor.author","Sasse, André"],["dc.contributor.author","Elsner, Leslie"],["dc.contributor.author","Paulus, Walter"],["dc.contributor.author","Trenkwalder, Claudia"],["dc.contributor.author","Polić, Bojan"],["dc.contributor.author","Mansouri, Ahmed"],["dc.contributor.author","Guan, Kaomei"],["dc.contributor.author","Dressel, Ralf"],["dc.date.accessioned","2019-07-09T11:43:35Z"],["dc.date.available","2019-07-09T11:43:35Z"],["dc.date.issued","2017"],["dc.description.abstract","Natural killer (NK) cells play an important role as cytotoxic effector cells, which scan the organism for infected or tumorigenic cells. Conflicting data have been published whether NK cells can also kill allogeneic or even autologous pluripotent stem cells (PSCs) and which receptors are involved. A clarification of this question is relevant since an activity of NK cells against PSCs could reduce the risk of teratoma growth after transplantation of PSC-derived grafts. Therefore, the hypothesis has been tested that the activity of NK cells against PSCs depends on cytokine activation and specifically on the activating NK receptor NKG2D. It is shown that a subcutaneous injection of autologous iPSCs failed to activate NK cells against these iPSCs and can give rise to teratomas. In agreement with this result, several PSC lines, including two iPSC, two embryonic stem cell (ESC), and two so-called multipotent adult germline stem cell (maGSC) lines, were largely resistant against resting NK cells although differences in killing were found at low level. All PSC lines were killed by interleukin (IL)-2-activated NK cells, and maGSCs were better killed than the other PSC types. The PSCs expressed ligands of the activating NK receptor NKG2D and NKG2D-deficient NK cells from Klrk1−/− mice were impaired in their cytotoxic activity against PSCs. The low-cytotoxic activity of resting NK cells was almost completely dependent on NKG2D. The cytotoxic activity of IL-2-activated NKG2D-deficient NK cells against PSCs was reduced, indicating that also other activating receptors on cytokine-activated NK cells must be engaged by ligands on PSCs. Thus, NKG2D is an important activating receptor involved in killing of murine PSCs. However, NK cells need to be activated by cytokines before they efficiently target PSCs and then also other NK receptors become relevant. These features of NK cells might be relevant for transplantation of PSC-derived grafts since NK cells have the capability to kill undifferentiated cells, which might be present in grafts in trace amounts."],["dc.identifier.doi","10.3389/fimmu.2017.00870"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14587"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58923"],["dc.identifier.url","https://sfb1002.med.uni-goettingen.de/production/literature/publications/297"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation","SFB 1002: Modulatorische Einheiten bei Herzinsuffizienz"],["dc.relation","SFB 1002 | C05: Bedeutung von zellulären Immunreaktionen für das kardiale Remodeling und die Therapie der Herzinsuffizienz durch Stammzelltransplantation"],["dc.relation.eissn","1664-3224"],["dc.relation.issn","1664-3224"],["dc.relation.workinggroup","RG Dressel"],["dc.relation.workinggroup","RG Guan (Application of patient-specific induced pluripotent stem cells in disease modelling)"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","610"],["dc.title","Efficient Killing of Murine Pluripotent Stem Cells by Natural Killer (NK) Cells Requires Activation by Cytokines and Partly Depends on the Activating NK Receptor NKG2D"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]