@phdthesis{Rauschenberger2021, author = {Rauschenberger, Vera}, title = {Stiff-person syndrome - Pathophysiological mechanisms of glycine receptor autoantibodies}, doi = {10.25972/OPUS-20958}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-209588}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {The Stiff-person syndrome (SPS) is a rare autoimmune disease that is characterized by symptoms including stiffness in axial and limb muscles as well as painful spasms. Different variants of SPS are known ranging from moderate forms like the stiff-limb syndrome to the most severe form progressive encephalomyelitis with rigidity and myoclonus (PERM). SPS is elicited by autoantibodies that target different pre- or postsynaptic proteins. The focus of the present work is on autoantibodies against the glycine receptor (GlyR). At start of the present thesis, as main characteristic of the GlyR autoantibody pathology, receptor cross-linking followed by enhanced receptor internalization and degradation via the lysosomal pathway was described. If binding of autoantibodies modulates GlyR function and therefore contributes to the GlyR autoantibody pathology has not yet been investigated. Moreover, not all patients respond well to plasmapheresis or other treatments used in the clinic. Relapses with even higher autoantibody titers regularly occur. In the present work, further insights into the disease pathology of GlyRα autoantibodies were achieved. We identified a common GlyRα1 autoantibody epitope located in the far N-terminus including amino acids A1-G34 which at least represent a part of the autoantibody epitope. This part of the receptor is easily accessible for autoantibodies due to its location at the outermost surface of the GlyRα1 extracellular domain. It was further investigated if the glycosylation status of the GlyR interferes with autoantibody binding. Using a GlyRα1 de-glycosylation mutant exhibited that patient autoantibodies are able to detect the de-glycosylated GlyRα1 variant as well. The direct modulation of the GlyR analyzed by electrophysiological recordings demonstrated functional alterations of the GlyR upon autoantibody binding. Whole cell patch clamp recordings revealed that autoantibodies decreased the glycine potency, shown by increased EC50 values. Furthermore, an influence on the desensitization behavior of the receptor was shown. The GlyR autoantibodies, however, had no impact on the binding affinity of glycine. These issues can be explained by the localization of the GlyR autoantibody epitope. The determined epitope has been exhibited to influence GlyR desensitization upon binding of allosteric modulators and differs from the orthosteric binding site for glycine, which is localized much deeper in the structure at the interface between two adjacent subunits. To neutralize GlyR autoantibodies, two different methods have been carried out. Transfected HEK293 cells expressing GlyRα1 and ELISA plates coated with the GlyRα1 extracellular domain were used to efficiently neutralize the autoantibodies. Finally, the successful passive transfer of GlyRα1 autoantibodies into zebrafish larvae and mice was shown. The autoantibodies detected their target in spinal cord and brain regions rich in GlyRs of zebrafish and mice. A passive transfer of human GlyRα autoantibodies to zebrafish larvae generated an impaired escape behavior in the animals compatible with the abnormal startle response in SPS or PERM patients.}, subject = {Glycinrezeptor}, language = {en} } @article{ZieglerEhlisWeberetal.2021, author = {Ziegler, Georg C. and Ehlis, Ann-Christine and Weber, Heike and Vitale, Maria Rosaria and Z{\"o}ller, Johanna E. M. and Ku, Hsing-Ping and Schiele, Miriam A. and K{\"u}rbitz, Laura I. and Romanos, Marcel and Pauli, Paul and Kalisch, Raffael and Zwanzger, Peter and Domschke, Katharina and Fallgatter, Andreas J. and Reif, Andreas and Lesch, Klaus-Peter}, title = {A Common CDH13 Variant is Associated with Low Agreeableness and Neural Responses to Working Memory Tasks in ADHD}, series = {Genes}, volume = {12}, journal = {Genes}, number = {9}, issn = {2073-4425}, doi = {10.3390/genes12091356}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245220}, year = {2021}, abstract = {The cell—cell signaling gene CDH13 is associated with a wide spectrum of neuropsychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD), autism, and major depression. CDH13 regulates axonal outgrowth and synapse formation, substantiating its relevance for neurodevelopmental processes. Several studies support the influence of CDH13 on personality traits, behavior, and executive functions. However, evidence for functional effects of common gene variation in the CDH13 gene in humans is sparse. Therefore, we tested for association of a functional intronic CDH13 SNP rs2199430 with ADHD in a sample of 998 adult patients and 884 healthy controls. The Big Five personality traits were assessed by the NEO-PI-R questionnaire. Assuming that altered neural correlates of working memory and cognitive response inhibition show genotype-dependent alterations, task performance and electroencephalographic event-related potentials were measured by n-back and continuous performance (Go/NoGo) tasks. The rs2199430 genotype was not associated with adult ADHD on the categorical diagnosis level. However, rs2199430 was significantly associated with agreeableness, with minor G allele homozygotes scoring lower than A allele carriers. Whereas task performance was not affected by genotype, a significant heterosis effect limited to the ADHD group was identified for the n-back task. Heterozygotes (AG) exhibited significantly higher N200 amplitudes during both the 1-back and 2-back condition in the central electrode position Cz. Consequently, the common genetic variation of CDH13 is associated with personality traits and impacts neural processing during working memory tasks. Thus, CDH13 might contribute to symptomatic core dysfunctions of social and cognitive impairment in ADHD.}, language = {en} } @article{BankogluSchueleStopper2021, author = {Bankoglu, Ezgi Eyluel and Schuele, Carolin and Stopper, Helga}, title = {Cell survival after DNA damage in the comet assay}, series = {Archives of Toxicology}, volume = {95}, journal = {Archives of Toxicology}, number = {12}, doi = {10.1007/s00204-021-03164-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265339}, pages = {3803-3813}, year = {2021}, abstract = {The comet assay is widely used in basic research, genotoxicity testing, and human biomonitoring. However, interpretation of the comet assay data might benefit from a better understanding of the future fate of a cell with DNA damage. DNA damage is in principle repairable, or if extensive, can lead to cell death. Here, we have correlated the maximally induced DNA damage with three test substances in TK6 cells with the survival of the cells. For this, we selected hydrogen peroxide (H\(_{2}\)O\(_{2}\)) as an oxidizing agent, methyl methanesulfonate (MMS) as an alkylating agent and etoposide as a topoisomerase II inhibitor. We measured cell viability, cell proliferation, apoptosis, and micronucleus frequency on the following day, in the same cell culture, which had been analyzed in the comet assay. After treatment, a concentration dependent increase in DNA damage and in the percentage of non-vital and apoptotic cells was found for each substance. Values greater than 20-30\% DNA in tail caused the death of more than 50\% of the cells, with etoposide causing slightly more cell death than H\(_{2}\)O\(_{2}\) or MMS. Despite that, cells seemed to repair of at least some DNA damage within few hours after substance removal. Overall, the reduction of DNA damage over time is due to both DNA repair and death of heavily damaged cells. We recommend that in experiments with induction of DNA damage of more than 20\% DNA in tail, survival data for the cells are provided.}, language = {en} } @phdthesis{HilligardtgebRueck2021, author = {Hilligardt [geb. R{\"u}ck], Deborah}, title = {Methylierung pro- und antiinflammatorischer T-Helfer-Zell-spezifischer Transkriptionsfaktoren bei ausgew{\"a}hlten Krankheitsbildern}, doi = {10.25972/OPUS-24949}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-249499}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Die Regulation krankheitsrelevanter Gene und deren Proteine {\"u}ber Ver{\"a}nderungen in der DNA-Methylierung stellen einen wichtigen und zugleich noch unzureichend erforschten Bereich bei Erkrankungen mit inflammatorischer Komponente dar. In dieser Arbeit wurde die Methylierung pro- und antiinflammatorischer Gene im hypoxischen Setting hervorgerufen durch Pr{\"a}eklampsie, Angsterkrankung und Inflammation bei Sklerodermie untersucht. Zur Bestimmung der prozentualen Methylierung wurde Pyrosequenzierung durchgef{\"u}hrt. Bei einem Teil der Proben erfolgte zus{\"a}tzlich die Bestimmung der Genexpression mittels Real Time PCR. Bei Angsterkrankung zeigte sich eine signifikante Hypermethylierung am Promotor des Treg spezifischen Transkriptionsfaktors FOXP3. Daraus k{\"o}nnte eine beeintr{\"a}chtigte Funktion der Tregs und somit eine erh{\"o}hte Komorbidit{\"a}t resultieren. In der Gruppe der an Sklerodermie erkrankten Personen zeigte sich entgegen den Erwartungen eine signifikant h{\"o}here RORC1 und RORC2 Methylierung. Eine Genexpressionsanalyse erbrachte eine signifikant niedrigere Expression von RORC bei Sklerodermie im Vergleich zu gesunden Kontrollen. Diese {\"u}berraschenden Ergebnisse k{\"o}nnten der Methodik geschuldet sein. Auf eine Auftrennung der verschiedenen T-Zellen vor Messung der Methylierung wurde verzichtet. Plazentagewebe bei Pr{\"a}eklampsie zeigte eine signifikant geringere Methylierung am FOXP3 Promotor als Plazentagewebe von gesunden Schwangeren. Die Ver{\"a}nderbarkeit der DNA-Methylierung durch {\"a}ußere Einfl{\"u}sse und Medikamente stellt hierbei einen vielversprechenden Ansatzpunkt f{\"u}r zuk{\"u}nftige Therapien dar und sollte in weiteren Studien konkretisiert werden.}, subject = {Methylierung}, language = {de} } @phdthesis{Volk2021, author = {Volk, Simone}, title = {Prospektiv-randomisierte, kontrollierte Evaluation der Auswirkungen zweier postoperativer Nachbehandlungskonzepte auf die Rerupturrate nach operativer Rekonstruktion der Rotatorenmanschette}, doi = {10.25972/OPUS-24954}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-249547}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Aufgrund der divergierenden Studienlage bez{\"u}glich der physiotherapeutischen Nachbehandlung nach operativer Rotatorenmanschettenrefixation erfolgte im Rahmen einer prospektiv randomisierten Studie die Evaluation zweier Nachbehandlungsmodelle nach operativer Refixation vollschichtiger RM-Rupturen in Mini-Open-Technik. Hierf{\"u}r wurden 57 Patienten pr{\"a}operativ, 3 Wochen, 6 Wochen sowie 6 Monate postoperativ nachuntersucht und ausgewertet. Die Scores beinhalteten den NRS-Score, Constant-Score, DASH-Score, ASES-Score, NHP-Score, SF-36-Score sowie eine sonographische Untersuchung zur Beurteilung der Reruptur nach 6 Monaten postoperativ. Einheitlich erfolgte die Ruhigstellung im Gilchrist-Verband f{\"u}r 6 Wochen. In der konservativen Nachbehandlungsgruppe wurden bis 6 Wochen postoperativ lediglich Pendel{\"u}bungen durchgef{\"u}hrt, in der progressiven Nachbehandlungsgruppe erfolgte eine passive Be{\"u}bung direkt postoperativ bis an die Schmerzgrenze mit Ausnahme der Adduktion. Im Gesamtkollektiv war eine Rerupturrate von 5,3\% zu verzeichnen mit 3,7\% in der konservativen und 6,7\% in der progressiven Nachbehandlungsgruppe ohne signifikanten Gruppenunterschied (p=0,540). Bez{\"u}glich der klinischen und psychischen Ergebnisse zeigte sich 6 Monate postoperativ lediglich eine Einschr{\"a}nkung der aktiven Außenrotation in der konservativen Nachbehandlungsgruppe (46,2∘ vs. 39,7∘, p=0,031), sonst war kein signifikanter Gruppenunterschied zu sehen. Weiterhin erfolgten Subgruppenanalysen insbesondere hinsichtlich Alter und Geschlecht der Patienten. Dabei haben Patienten {\"u}ber 65 Jahren unabh{\"a}ngig von der Nachbehandlungsgruppe k{\"u}rzer Analgetika eingenommen und waren 6 Wochen postoperativ weniger bewegungseingeschr{\"a}nkt. Aufgrund einer Tendenz zu vermehrten Rerupturen nach progressiver Nachbehandlung in der Literatur werden daher weiterf{\"u}hrende Studien ben{\"o}tigt um zu evaluieren, ob {\"a}ltere Patienten von einer vermehrten Ruhigstellung profitieren k{\"o}nnten. Diese Studie pr{\"a}sentiert im Gegensatz zu der {\"u}berwiegend in der Literatur verwendeten arthroskopischen OP-Technik Ergebnisse nach RM-Refixation in Mini-Open-Technik. Damit liefert sie eine gute Grundlage f{\"u}r weiterf{\"u}hrende Studien insbesondere in der Behandlung von gr{\"o}ßeren RM-Rupturen, welche ein erh{\"o}htes Rerupturrisiko besitzen und von einer konservativen Nachbehandlung profitieren k{\"o}nnten.}, subject = {Rotatorenmanschettenruptur}, language = {de} } @phdthesis{Fuchs2021, author = {Fuchs, Katharina}, title = {Validierung verschiedener pr{\"a}disponierender Faktoren f{\"u}r die Entwicklung eines Lagerungsplagiozephalus}, doi = {10.25972/OPUS-25147}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-251471}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2021}, abstract = {Bei seiner Geburt und innerhalb der ersten Lebensmonate ist der S{\"a}uglingssch{\"a}del verh{\"a}ltnism{\"a}ßig leicht verformbar. Dies birgt die Gefahr einer unphysiologischen Verformung durch externe modellierende Kr{\"a}fte. Die auf diesem Weg am h{\"a}ufigsten verursachte Deformation ist der Lagerungsplagiozephalus (LP). In der vorliegenden Studie wurden 455 S{\"a}uglinge, die zun{\"a}chst in drei unterschiedliche Gruppen bez{\"u}glich ihrer Kopfform unterteilt worden sind, hinsichtlich verschiedener Parameter miteinander verglichen. Anhand des U-Heftes und einem speziell f{\"u}r die craniofaciale Sprechstunde des CFCW W{\"u}rzburg angefertigten Fragebogen wurden Pr{\"a}diktoren f{\"u}r die Entwicklung eines LP evaluiert. Die herausgearbeiteten pr{\"a}disponierenden Faktoren waren das m{\"a}nnliche Geschlecht, Fr{\"u}hgeburtlichkeit, eine unphysiologische Geburtslage, Notkaiserschnitt oder geburtshilfliche Maßnahmen, verminderte Geburtsgr{\"o}ße, vermindertes Geburtsgewicht und ein l{\"a}ngerer Krankenhausaufenthalt im Anschluss an die Geburt. Als prognostisch g{\"u}nstiger Faktor hinsichtlich der Entwicklung einer physiologischen Sch{\"a}delform konnte in der vorliegenden Studie eine l{\"a}ngere Stilldauer best{\"a}tigt werden. Dies galt ebenso f{\"u}r Gabe von Flaschennahrung aus alternierenden Positionen. Hinsichtlich der pr{\"a}ventiven Aufkl{\"a}rung von Eltern Neugeborener liefert die vorliegende Studie einige wichtige Ans{\"a}tze. Sie untermauert jedoch auch den hohen Bedarf an weiterer Forschung bez{\"u}glich pr{\"a}disponierender Faktoren f{\"u}r die Entwicklung des LP. Dies kann dazu beitragen die Pr{\"a}vention und Fr{\"u}herkennung eines LP mittels fl{\"a}chendeckender qualitativ hochwertiger Aufkl{\"a}rung stetig zu verbessern und notwendig gewordene Behandlungen durch standardisierte Therapieempfehlungen zu optimieren.}, subject = {Lagerungsplagiozephalus}, language = {de} } @article{KuhlemannBeliuJanzenetal.2021, author = {Kuhlemann, Alexander and Beliu, Gerti and Janzen, Dieter and Petrini, Enrica Maria and Taban, Danush and Helmerich, Dominic A. and Doose, S{\"o}ren and Bruno, Martina and Barberis, Andrea and Villmann, Carmen and Sauer, Markus and Werner, Christian}, title = {Genetic Code Expansion and Click-Chemistry Labeling to Visualize GABA-A Receptors by Super-Resolution Microscopy}, series = {Frontiers in Synaptic Neuroscience}, volume = {13}, journal = {Frontiers in Synaptic Neuroscience}, issn = {1663-3563}, doi = {10.3389/fnsyn.2021.727406}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-251035}, year = {2021}, abstract = {Fluorescence labeling of difficult to access protein sites, e.g., in confined compartments, requires small fluorescent labels that can be covalently tethered at well-defined positions with high efficiency. Here, we report site-specific labeling of the extracellular domain of γ-aminobutyric acid type A (GABA-A) receptor subunits by genetic code expansion (GCE) with unnatural amino acids (ncAA) combined with bioorthogonal click-chemistry labeling with tetrazine dyes in HEK-293-T cells and primary cultured neurons. After optimization of GABA-A receptor expression and labeling efficiency, most effective variants were selected for super-resolution microscopy and functionality testing by whole-cell patch clamp. Our results show that GCE with ncAA and bioorthogonal click labeling with small tetrazine dyes represents a versatile method for highly efficient site-specific fluorescence labeling of proteins in a crowded environment, e.g., extracellular protein domains in confined compartments such as the synaptic cleft.}, language = {en} } @article{PetersKaiserFinketal.2021, author = {Peters, Simon and Kaiser, Lena and Fink, Julian and Schumacher, Fabian and Perschin, Veronika and Schlegel, Jan and Sauer, Markus and Stigloher, Christian and Kleuser, Burkhard and Seibel, Juergen and Schubert-Unkmeir, Alexandra}, title = {Click-correlative light and electron microscopy (click-AT-CLEM) for imaging and tracking azido-functionalized sphingolipids in bacteria}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-021-83813-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259147}, pages = {4300}, year = {2021}, abstract = {Sphingolipids, including ceramides, are a diverse group of structurally related lipids composed of a sphingoid base backbone coupled to a fatty acid side chain and modified terminal hydroxyl group. Recently, it has been shown that sphingolipids show antimicrobial activity against a broad range of pathogenic microorganisms. The antimicrobial mechanism, however, remains so far elusive. Here, we introduce 'click-AT-CLEM', a labeling technique for correlated light and electron microscopy (CLEM) based on the super-resolution array tomography (srAT) approach and bio-orthogonal click chemistry for imaging of azido-tagged sphingolipids to directly visualize their interaction with the model Gram-negative bacterium Neisseria meningitidis at subcellular level. We observed ultrastructural damage of bacteria and disruption of the bacterial outer membrane induced by two azido-modified sphingolipids by scanning electron microscopy and transmission electron microscopy. Click-AT-CLEM imaging and mass spectrometry clearly revealed efficient incorporation of azido-tagged sphingolipids into the outer membrane of Gram-negative bacteria as underlying cause of their antimicrobial activity.}, language = {en} } @article{FioreVaccaTuminoetal.2021, author = {Fiore, Piera Filomena and Vacca, Paola and Tumino, Nicola and Besi, Francesca and Pelosi, Andrea and Munari, Enrico and Marconi, Marcella and Caruana, Ignazio and Pistoia, Vito and Moretta, Lorenzo and Azzarone, Bruno}, title = {Wilms' tumor primary cells display potent immunoregulatory properties on NK cells and macrophages}, series = {Cancers}, volume = {13}, journal = {Cancers}, number = {2}, issn = {2072-6694}, doi = {10.3390/cancers13020224}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-222981}, year = {2021}, abstract = {The immune response plays a crucial defensive role in cancer growth and metastasis and is a promising target in different tumors. The role of the immune system in Wilm's Tumor (WT), a common pediatric renal malignancy, is still to be explored. The characterization of the immune environment in WT could allow the identification of new therapeutic strategies for targeting possible inhibitory mechanisms and/or lowering toxicity of the current treatments. In this study, we stabilized four WT primary cultures expressing either a blastematous (CD56\(^+\)/CD133\(^-\)) or an epithelial (CD56\(^-\)/CD133\(^+\)) phenotype and investigated their interactions with innate immune cells, namely NK cells and monocytes. We show that cytokine-activated NK cells efficiently kill WT cells. However, after co-culture with WT primary cells, NK cells displayed an impaired cytotoxic activity, decreased production of IFNγ and expression of CD107a, DNAM-1 and NKp30. Analysis of the effects of the interaction between WT cells and monocytes revealed their polarization towards alternatively activated macrophages (M2) that, in turn, further impaired NK cell functions. In conclusion, we show that both WT blastematous and epithelial components may contribute directly and indirectly to a tumor immunosuppressive microenvironment that is likely to play a role in tumor progression.}, language = {en} } @article{PiroEckesKasaragodetal.2021, author = {Piro, Inken and Eckes, Anna-Lena and Kasaragod, Vikram Babu and Sommer, Claudia and Harvey, Robert J. and Schaefer, Natascha and Villmann, Carmen}, title = {Novel Functional Properties of Missense Mutations in the Glycine Receptor β Subunit in Startle Disease}, series = {Frontiers in Molecular Neuroscience}, volume = {14}, journal = {Frontiers in Molecular Neuroscience}, issn = {1662-5099}, doi = {10.3389/fnmol.2021.745275}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246676}, year = {2021}, abstract = {Startle disease is a rare disorder associated with mutations in GLRA1 and GLRB, encoding glycine receptor (GlyR) α1 and β subunits, which enable fast synaptic inhibitory transmission in the spinal cord and brainstem. The GlyR β subunit is important for synaptic localization via interactions with gephyrin and contributes to agonist binding and ion channel conductance. Here, we have studied three GLRB missense mutations, Y252S, S321F, and A455P, identified in startle disease patients. For Y252S in M1 a disrupted stacking interaction with surrounding aromatic residues in M3 and M4 is suggested which is accompanied by an increased EC\(_{50}\) value. By contrast, S321F in M3 might stabilize stacking interactions with aromatic residues in M1 and M4. No significant differences in glycine potency or efficacy were observed for S321F. The A455P variant was not predicted to impact on subunit folding but surprisingly displayed increased maximal currents which were not accompanied by enhanced surface expression, suggesting that A455P is a gain-of-function mutation. All three GlyR β variants are trafficked effectively with the α1 subunit through intracellular compartments and inserted into the cellular membrane. In vivo, the GlyR β subunit is transported together with α1 and the scaffolding protein gephyrin to synaptic sites. The interaction of these proteins was studied using eGFP-gephyrin, forming cytosolic aggregates in non-neuronal cells. eGFP-gephyrin and β subunit co-expression resulted in the recruitment of both wild-type and mutant GlyR β subunits to gephyrin aggregates. However, a significantly lower number of GlyR β aggregates was observed for Y252S, while for mutants S321F and A455P, the area and the perimeter of GlyR β subunit aggregates was increased in comparison to wild-type β. Transfection of hippocampal neurons confirmed differences in GlyR-gephyrin clustering with Y252S and A455P, leading to a significant reduction in GlyR β-positive synapses. Although none of the mutations studied is directly located within the gephyrin-binding motif in the GlyR β M3-M4 loop, we suggest that structural changes within the GlyR β subunit result in differences in GlyR β-gephyrin interactions. Hence, we conclude that loss- or gain-of-function, or alterations in synaptic GlyR clustering may underlie disease pathology in startle disease patients carrying GLRB mutations.}, language = {en} }