TY - JOUR A1 - Wörsdörfer, Philipp A1 - I, Takashi A1 - Asahina, Izumi A1 - Sumita, Yoshinori A1 - Ergün, Süleyman T1 - Do not keep it simple: recent advances in the generation of complex organoids JF - Journal of Neural Transmission N2 - 3D cell culture models which closely resemble real human tissues are of high interest for disease modelling, drug screening as well as a deeper understanding of human developmental biology. Such structures are termed organoids. Within the last years, several human organoid models were described. These are usually stem cell derived, arise by self-organization, mimic mechanisms of normal tissue development, show typical organ morphogenesis and recapitulate at least some organ specific functions. Many tissues have been reproduced in vitro such as gut, liver, lung, kidney and brain. The resulting entities can be either derived from an adult stem cell population, or generated from pluripotent stem cells using a specific differentiation protocol. However, many organoid models only recapitulate the organs parenchyma but are devoid of stromal components such as blood vessels, connective tissue and inflammatory cells. Recent studies show that the incorporation of endothelial and mesenchymal cells into organoids improved their maturation and might be required to create fully functional micro-tissues, which will allow deeper insights into human embryogenesis as well as disease development and progression. In this review article, we will summarize and discuss recent works trying to incorporate stromal components into organoids, with a special focus on neural organoid models. KW - organoid KW - stroma KW - sasculature KW - neural KW - microglia KW - blood vessel Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235628 SN - 0300-9564 VL - 127 ER - TY - JOUR A1 - Wörsdörfer, Philipp A1 - Ergün, Süleyman T1 - “Organoids”: insights from the first issues JF - Organoids N2 - No abstract available KW - organoids KW - editorial Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313694 SN - 2674-1172 VL - 2 IS - 2 SP - 79 EP - 81 ER - TY - JOUR A1 - Wörsdörfer, Philipp A1 - Dalda, Nahide A1 - Kern, Anna A1 - Krüger, Sarah A1 - Wagner, Nicole A1 - Kwok, Chee Keong A1 - Henke, Erik A1 - Ergün, Süleyman T1 - Generation of complex human organoid models including vascular networks by incorporation of mesodermal progenitor cells JF - Scientific Reports N2 - Organoids derived from human pluripotent stem cells are interesting models to study mechanisms of morphogenesis and promising platforms for disease modeling and drug screening. However, they mostly remain incomplete as they lack stroma, tissue resident immune cells and in particular vasculature, which create important niches during development and disease. We propose, that the directed incorporation of mesodermal progenitor cells (MPCs) into organoids will overcome the aforementioned limitations. In order to demonstrate the feasibility of the method, we generated complex human tumor as well as neural organoids. We show that the formed blood vessels display a hierarchic organization and mural cells are assembled into the vessel wall. Moreover, we demonstrate a typical blood vessel ultrastructure including endothelial cell-cell junctions, a basement membrane as well as luminal caveolae and microvesicles. We observe a high plasticity in the endothelial network, which expands, while the organoids grow and is responsive to anti-angiogenic compounds and pro-angiogenic conditions such as hypoxia. We show that vessels within tumor organoids connect to host vessels following transplantation. Remarkably, MPCs also deliver Iba1\(^+\) cells that infiltrate the neural tissue in a microglia-like manner. KW - Developmental biology KW - Stem cells Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202681 VL - 9 ER - TY - JOUR A1 - Wunsch, Marie A1 - Hohmann, Christopher A1 - Milles, Bianca A1 - Rostermund, Christina A1 - Lehmann, Paul V. A1 - Schroeter, Michael A1 - Bayas, Antonios A1 - Ulzheimer, Jochen A1 - Mäurer, Mathias A1 - Ergün, Süleyman A1 - Kuerten, Stefanie T1 - The Correlation between the Virus- and Brain Antigen-Specific B Cell Response in the Blood of Patients with Multiple Sclerosis JF - Viruses N2 - There is a largely divergent body of literature regarding the relationship between Epstein-Barr virus (EBV) infection and brain inflammation in multiple sclerosis (MS). Here, we tested MS patients during relapse (n = 11) and in remission (n = 19) in addition to n = 22 healthy controls to study the correlation between the EBV- and brain-specific B cell response in the blood by enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). Cytomegalovirus (CMV) was used as a control antigen tested in n = 16 MS patients during relapse and in n = 35 patients in remission. Over the course of the study, n = 16 patients were untreated, while n = 33 patients received immunomodulatory therapy. The data show that there was a moderate correlation between the frequencies of EBV- and brain-reactive B cells in MS patients in remission. In addition we could detect a correlation between the B cell response to EBV and disease activity. There was no evidence of an EBV reactivation. Interestingly, there was also a correlation between the frequencies of CMV- and brain-specific B cells in MS patients experiencing an acute relapse and an elevated B cell response to CMV was associated with higher disease activity. The trend remained when excluding seronegative subjects but was non-significant. These data underline that viral infections might impact the immunopathology of MS, but the exact link between the two entities remains subject of controversy. KW - B cells KW - CMV KW - EBV KW - ELISPOT KW - MS Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146946 VL - 8 IS - 4 ER - TY - JOUR A1 - Wiegering, Armin A1 - Korb, Doreen A1 - Thalheimer, Andreas A1 - Kämmerer, Ulrike A1 - Allmanritter, Jan A1 - Matthes, Niels A1 - Linnebacher, Michael A1 - Schlegel, Nicolas A1 - Klein, Ingo A1 - Ergün, Süleyman A1 - Germer, Christoph-Thomas A1 - Otto, Christoph T1 - E7080 (Lenvatinib), a Multi-Targeted Tyrosine Kinase Inhibitor, Demonstrates Antitumor Activities Against Colorectal Cancer Xenografts N2 - Clinical prognosis of metastasized colorectal carcinoma (CRC) is still not at desired levels and novel drugs are needed. Here, we focused on the multi-tyrosine kinase inhibitor E7080 (Lenvatinib) and assessed its therapeutic efficacy against human CRC cell lines in vitro and human CRC xenografts in vivo. The effect of E7080 on cell viability was examined on 10 humanCRCcell lines and humanendothelial cells (HUVEC). The inhibitory effect of E7080 on VEGF-induced angiogenesis was studied in an ex vivo mouse aortic ring angiogenesis assay. In addition, the efficacy of E7080 against xenografts derived fromCRC cell lines and CRC patient resection specimenswithmutated KRASwas investigated in vivo. Arelatively low cytotoxic effect of E7080 on CRC cell viabilitywas observed in vitro. Endothelial cells (HUVEC)weremore susceptible to the incubation with E7080. This is in line with the observation that E7080 demonstrated an anti-angiogenic effect in a three-dimensional ex vivo mouse aortic ring angiogenesis assay. E7080 effectively disrupted CRC cell-mediated VEGF-stimulated growth of HUVEC in vitro. Daily in vivo treatment with E7080 (5 mg/kg) significantly delayed the growth of KRAS mutated CRC xenografts with decreased density of tumor-associated vessel formations and without tumor regression. This observation is in line with results that E7080 did not significantly reduce the number of Ki67-positive cells in CRC xenografts. The results suggest antiangiogenic activity of E7080 at a dosage thatwas well tolerated by nudemice. E7080 may provide therapeutic benefits in the treatment of CRC with mutated KRAS. KW - Chirurgie Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111165 ER - TY - CHAP A1 - Werner, Rudolf A1 - Wakabayashi, Hiroshi A1 - Jahns, Roland A1 - Ergün, Süleyman A1 - Jahns, Valerie A1 - Higuchi, Takahiro T1 - PET-Guided Histological Characterization of Myocardial Infiltrating Cells in a Rat Model of Myocarditis T2 - European Heart Journal - Cardiovascular Imaging N2 - No abstract available. KW - Myokarditis KW - positron emission tomography KW - myocarditis KW - PET KW - 18F-FDG Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-161127 SN - 2047-2404 N1 - This is a pre-copyedited, author-produced version of an article accepted for publication in European Heart Journal Cardiovascular Imaging following peer review. The version of record . Eur Heart J Cardiovasc Imaging. ISSN: 2047-2404. Supplement, vol. 18, i1-i3, May 2017 is available online at: 10.1093/ehjci/jex071. VL - 18 IS - Supplement PB - Oxford University Press ER - TY - JOUR A1 - Werner, Rudolf A1 - Wakabayashi, Hiroshi A1 - Bauer, Jochen A1 - Schütz, Claudia A1 - Zechmeister, Christina A1 - Hayakawa, Nobuyuki A1 - Javadi, Mehrbod S. A1 - Lapa, Constantin A1 - Jahns, Roland A1 - Ergün, Süleyman A1 - Jahns, Valerie A1 - Higuchi, Takahiro T1 - Longitudinal \(^{18}\)F-FDG PET imaging in a Rat Model of Autoimmune Myocarditis JF - European Heart Journal Cardiovascular Imaging N2 - Aims: Although mortality rate is very high, diagnosis of acute myocarditis remains challenging with conventional tests. We aimed to elucidate the potential role of longitudinal 2-Deoxy-2-\(^{18}\)F-fluoro-D-glucose (\(^{18}\)F-FDG) positron emission tomography (PET) inflammation monitoring in a rat model of experimental autoimmune myocarditis. Methods and results: Autoimmune myocarditis was induced in Lewis rats by immunizing with porcine cardiac myosin emulsified in complete Freund’s adjuvant. Time course of disease was assessed by longitudinal \(^{18}\)F-FDG PET imaging. A correlative analysis between in- and ex vivo \(^{18}\)F-FDG signalling and macrophage infiltration using CD68 staining was conducted. Finally, immunohistochemistry analysis of the cell-adhesion markers CD34 and CD44 was performed at different disease stages determined by longitudinal \(^{18}\)F-FDG PET imaging. After immunization, myocarditis rats revealed a temporal increase in 18F-FDG uptake (peaked at week 3), which was followed by a rapid decline thereafter. Localization of CD68 positive cells was well correlated with in vivo \(^{18}\)F-FDG PET signalling (R\(^2\) = 0.92) as well as with ex vivo 18F-FDG autoradiography (R\(^2\) = 0.9, P < 0.001, respectively). CD44 positivity was primarily observed at tissue samples obtained at acute phase (i.e. at peak 18F-FDG uptake), while CD34-positive staining areas were predominantly identified in samples harvested at both sub-acute and chronic phases (i.e. at \(^{18}\)F-FDG decrease). Conclusion: \(^{18}\)F-FDG PET imaging can provide non-invasive serial monitoring of cardiac inflammation in a rat model of acute myocarditis. KW - positron emission tomography KW - Myokarditis KW - myocarditis KW - inflammation KW - 18F-FDG KW - PET KW - personalized treatment Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165601 SN - 2047-2404 ER - TY - JOUR A1 - Wagner, Nicole A1 - Mott, Kristina A1 - Upcin, Berin A1 - Stegner, David A1 - Schulze, Harald A1 - Ergün, Süleyman T1 - CXCL12-abundant reticular (CAR) cells direct megakaryocyte protrusions across the bone marrow sinusoid wall JF - Cells N2 - Megakaryocytes (MKs) release platelets into the lumen of bone marrow (BM) sinusoids while remaining to reside within the BM. The morphogenetic events of this complex process are still not fully understood. We combined confocal laser scanning microscopy with transmission and serial block-face scanning electron microscopy followed by 3D-reconstruction on mouse BM tissue sections. These analyses revealed that MKs in close vicinity to BM sinusoid (BMS) wall first induce the lateral retraction of CXCL12-abundant reticular (CAR) cells (CAR), followed by basal lamina (BL) degradation enabling direct MK-sinusoidal endothelial cells (SECs) interaction. Subsequently, an endothelial engulfment starts that contains a large MK protrusion. Then, MK protrusions penetrate the SEC, transmigrate into the BMS lumen and form proplatelets that are in direct contact to the SEC surface. Furthermore, such processes are induced on several sites, as observed by 3D reconstructions. Our data demonstrate that MKs in interaction with CAR-cells actively induce BMS wall alterations, including CAR-cell retraction, BL degradation, and SEC engulfment containing a large MK protrusion. This results in SEC penetration enabling the migration of MK protrusion into the BMS lumen where proplatelets that are adherent to the luminal SEC surface are formed and contribute to platelet release into the blood circulation. KW - megakaryocytes KW - microvasculature KW - CXCL12-abundant reticular (CAR)-cells Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234180 SN - 2073-4409 VL - 10 IS - 4 ER - TY - JOUR A1 - Upcin, Berin A1 - Henke, Erik A1 - Kleefeldt, Florian A1 - Hoffmann, Helene A1 - Rosenwald, Andreas A1 - Irmak-Sav, Ster A1 - Aktas, Huseyin Bertal A1 - Rückschloß, Uwe A1 - Ergün, Süleyman T1 - Contribution of adventitia-derived stem and progenitor cells to new vessel formation in tumors JF - Cells N2 - Blocking tumor vascularization has not yet come to fruition to the extent it was hoped for, as angiogenesis inhibitors have shown only partial success in the clinic. We hypothesized that under- appreciated vascular wall-resident stem and progenitor cells (VW-SPCs) might be involved in tumor vascularization and influence effectiveness of anti-angiogenic therapy. Indeed, in patient samples, we observed that vascular adventitia-resident CD34\(^+\) VW-SPCs are recruited to tumors in situ from co-opted vessels. To elucidate this in detail, we established an ex vivo model using concomitant embedding of multi-cellular tumor spheroids (MCTS) and mouse aortic rings (ARs) into collagen gels, similar to the so-called aortic ring assay (ARA). Moreover, ARA was modified by removing the ARs’ adventitia that harbors VW-SPCs. Thus, this model enabled distinguishing the contribution of VW-SPCs from that of mature endothelial cells (ECs) to new vessel formation. Our results show that the formation of capillary-like sprouts is considerably delayed, and their number and network formation were significantly reduced by removing the adventitia. Substituting iPSC-derived neural spheroids for MCTS resulted in distinct sprouting patterns that were also strongly influenced by the presence or absence of VW-SPCs, also underlying the involvement of these cells in non-pathological vascularization. Our data suggest that more comprehensive approaches are needed in order to block all of the mechanisms contributing to tumor vascularization. KW - vascularization model KW - tumor spheroids KW - vascular wall stem and progenitor cells KW - aortic adventitia KW - vasculogenesis KW - tumor-vessel wall-interface model Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242577 VL - 10 IS - 7 ER - TY - JOUR A1 - Shityakov, Sergey A1 - Nagai, Michiaki A1 - Ergün, Süleyman A1 - Braunger, Barbara M. A1 - Förster, Carola Y. T1 - The protective effects of neurotrophins and microRNA in diabetic retinopathy, nephropathy and heart failure via regulating endothelial function JF - Biomolecules N2 - Diabetes mellitus is a common disease affecting more than 537 million adults worldwide. The microvascular complications that occur during the course of the disease are widespread and affect a variety of organ systems in the body. Diabetic retinopathy is one of the most common long-term complications, which include, amongst others, endothelial dysfunction, and thus, alterations in the blood-retinal barrier (BRB). This particularly restrictive physiological barrier is important for maintaining the neuroretina as a privileged site in the body by controlling the inflow and outflow of fluid, nutrients, metabolic end products, ions, and proteins. In addition, people with diabetic retinopathy (DR) have been shown to be at increased risk for systemic vascular complications, including subclinical and clinical stroke, coronary heart disease, heart failure, and nephropathy. DR is, therefore, considered an independent predictor of heart failure. In the present review, the effects of diabetes on the retina, heart, and kidneys are described. In addition, a putative common microRNA signature in diabetic retinopathy, nephropathy, and heart failure is discussed, which may be used in the future as a biomarker to better monitor disease progression. Finally, the use of miRNA, targeted neurotrophin delivery, and nanoparticles as novel therapeutic strategies is highlighted. KW - diabetic retinopathy KW - diabetes mellitus KW - microvascular complications KW - diabetic nephropathy KW - heart failure KW - microRNA KW - neurotrophins Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285966 SN - 2218-273X VL - 12 IS - 8 ER -