@phdthesis{Geis2004,
  author    = {Geis, Christian},
  title     = {Charakterisierung von Spinalganglienneuronen intakter und l{\"a}dierter Afferenzen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-13926},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2004},
  abstract  = {Am Tiermodell einer experimentellen Mononeuropathie (chronic constriction injury, CCI) wurde bei Ratten die Expression von Zytokinen (TNF-\&\#945;, IL-10), Vanilloidrezeptor 1 (VR1) und Neuropeptiden in Spinalganglienneuronen immunhistochemisch analy-siert. Durch retrograde Anf{\"a}rbung mit den Tracern Fluorogold (FG) und Fluoruby (FR) konnten intakte von gesch{\"a}digten Neuronen unterschieden und Muskel- und Hautaffe-renzen getrennt untersucht werden. Nach CCI fand sich ein selektiver Anstieg der TNF-\&\#945; Immunreaktivit{\"a}t in mittelgroßen und großen Spinalganglienneuronen, welche durch Vergleich mit anderen neuronalen Markern als A-Faser Neurone identifiziert werden konnten. Nicht nur gesch{\"a}digte, sondern auch intakte Spinalganglienneurone wiesen eine erh{\"o}hte TNF-\&\#945; Immunreaktivit{\"a}t auf und sowohl Muskel- als auch Hautafferenzen trugen zur vermehrten TNF-\&\#945; Expression bei. IL-10, VR1 und IB4 Immunreaktivit{\"a}t fand sich vor allem in kleinen Neuronen und war nach CCI deutlich reduziert, w{\"a}hrend die Expression von CGRP in kleinen und mittel-großen Spinalganglienneuronen nachzuweisen war und keine Ver{\"a}nderung zeigte. Die Ergebnisse zeigen, dass intakt gebliebene A-Faser Neurone pathophysiologische Ver{\"a}nderungen im Sinne einer vermehrten Expression des pro-inflammatorischen Zyto-kins TNF-\&\#945; erfahren. Dieser ph{\"a}notypische Switch ist m{\"o}glicherweise mit einer neuen Funktion dieser Neurone im nozizeptiven System verbunden. Die verminderte Expression des anti-inflammatorischen Zytokins IL-10 vier Tage nach CCI korrespondiert mit der fr{\"u}hen Schmerzentstehung nach peripherer Nervenl{\"a}sion und der noch fehlenden Suppression der pro-inflammatorischen Zytokine zu diesem Zeitpunkt. Dagegen ist der R{\"u}ckgang der VR1 und IB4 Konzentrationen im Spinal-ganglion am ehesten durch einen l{\"a}sionsbedingten Mangel an neurotrophen Faktoren zu erkl{\"a}ren. Die in dieser Arbeit gewonnenen Erkenntnisse unterst{\"u}tzen die These, dass pro-inflammatorischen Zytokinen, insbesondere TNF-\&\#945;, eine besondere Bedeutung bei der Entstehung neuropathischer Schmerzen zukommt. Dies k{\"o}nnte ein Ansatzpunkt f{\"u}r wei-tere Studien sein, die Wirksamkeit TNF-\&\#945; hemmender Medikamente bei neuropathi-schen Schmerzmodellen im Tierversuch und eventuell sp{\"a}ter klinisch zu untersuchen.},
  language  = {de}
}
@article{GunrebenGeisKleinschnitz2013,
  author    = {Gunreben, Ignaz and Geis, Christian and Kleinschnitz, Christoph},
  title     = {Acute tetraparesis secondary to bilateral precentral gyral cerebral ischemia: a case report},
  series = {Journal of Medical Case Reports},
  journal   = {Journal of Medical Case Reports},
  doi       = {10.1186/1752-1947-7-61},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96179},
  year      = {2013},
  abstract  = {Introduction Sudden tetraparesis represents a neurological emergency and is most often caused by traumatic spinal cord injury, spinal epidural bleeding or brainstem ischemia and less frequently by medial disc herniation or spinal ischemia. Case presentation Here we report the rare case of an 82-year-old Caucasian man who developed severe tetraparesis four days after radical cystoprostatectomy. An emergency diagnostic study for spinal cord affection was normal. Brain magnetic resonance imaging revealed acute bilateral ischemic strokes in the precentral gyri as the underlying cause. Conclusions This case report underlines the need to also consider unusual causes of tetraparesis in an emergency situation apart from spinal cord or brain stem injury in order not to leave severe symptomatology unclear and possibly miss therapeutic options.},
  language  = {en}
}
@article{GruenewaldBennettToykaetal.2016,
  author    = {Gr{\"u}newald, Benedikt and Bennett, Jeffrey L. and Toyka, Klaus V. and Sommer, Claudia and Geis, Christian},
  title     = {Efficacy of Polyvalent Human Immunoglobulins in an Animal Model of Neuromyelitis Optica Evoked by Intrathecal Anti-Aquaporin 4 Antibodies},
  series = {International Journal of Molecular Sciences},
  volume    = {17},
  journal   = {International Journal of Molecular Sciences},
  number    = {9},
  doi       = {10.3390/ijms17091407},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166000},
  pages     = {1407},
  year      = {2016},
  abstract  = {Neuromyelitis Optica Spectrum Disorders (NMOSD) are associated with autoantibodies (ABs) targeting the astrocytic aquaporin-4 water channels (AQP4-ABs). These ABs have a direct pathogenic role by initiating a variety of immunological and inflammatory processes in the course of disease. In a recently-established animal model, chronic intrathecal passive-transfer of immunoglobulin G from NMOSD patients (NMO-IgG), or of recombinant human AQP4-ABs (rAB-AQP4), provided evidence for complementary and immune-cell independent effects of AQP4-ABs. Utilizing this animal model, we here tested the effects of systemically and intrathecally applied pooled human immunoglobulins (IVIg) using a preventive and a therapeutic paradigm. In NMO-IgG animals, prophylactic application of systemic IVIg led to a reduced median disease score of 2.4 on a 0-10 scale, in comparison to 4.1 with sham treatment. Therapeutic IVIg, applied systemically after the 10th intrathecal NMO-IgG injection, significantly reduced the disease score by 0.8. Intrathecal IVIg application induced a beneficial effect in animals with NMO-IgG (median score IVIg 1.6 vs. sham 3.7) or with rAB-AQP4 (median score IVIg 2.0 vs. sham 3.7). We here provide evidence that treatment with IVIg ameliorates disease symptoms in this passive-transfer model, in analogy to former studies investigating passive-transfer animal models of other antibody-mediated disorders.},
  language  = {en}
}
@article{GruenewaldLangeWerneretal.2017,
  author    = {Gr{\"u}newald, Benedikt and Lange, Maren D and Werner, Christian and O'Leary, Aet and Weishaupt, Andreas and Popp, Sandy and Pearce, David A and Wiendl, Heinz and Reif, Andreas and Pape, Hans C and Toyka, Klaus V and Sommer, Claudia and Geis, Christian},
  title     = {Defective synaptic transmission causes disease signs in a mouse model of juvenile neuronal ceroid lipofuscinosis},
  series = {eLife},
  volume    = {6},
  journal   = {eLife},
  number    = {e28685},
  doi       = {10.7554/eLife.28685},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170004},
  year      = {2017},
  abstract  = {Juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease) caused by mutations in the CLN3 gene is the most prevalent inherited neurodegenerative disease in childhood resulting in widespread central nervous system dysfunction and premature death. The consequences of CLN3 mutation on the progression of the disease, on neuronal transmission, and on central nervous network dysfunction are poorly understood. We used Cln3 knockout (Cln3\(^{Δex1-6}\)) mice and found increased anxiety-related behavior and impaired aversive learning as well as markedly affected motor function including disordered coordination. Patch-clamp and loose-patch recordings revealed severely affected inhibitory and excitatory synaptic transmission in the amygdala, hippocampus, and cerebellar networks. Changes in presynaptic release properties may result from dysfunction of CLN3 protein. Furthermore, loss of calbindin, neuropeptide Y, parvalbumin, and GAD65-positive interneurons in central networks collectively support the hypothesis that degeneration of GABAergic interneurons may be the cause of supraspinal GABAergic disinhibition.},
  language  = {en}
}
@article{GrafRahmatiMajorosetal.2022,
  author    = {Graf, J{\"u}rgen and Rahmati, Vahid and Majoros, Myrtill and Witte, Otto W. and Geis, Christian and Kiebel, Stefan J. and Holthoff, Knut and Kirmse, Knut},
  title     = {Network instability dynamics drive a transient bursting period in the developing hippocampus in vivo},
  series = {eLife},
  volume    = {11},
  journal   = {eLife},
  doi       = {10.7554/eLife.82756},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-300906},
  year      = {2022},
  abstract  = {Spontaneous correlated activity is a universal hallmark of immature neural circuits. However, the cellular dynamics and intrinsic mechanisms underlying network burstiness in the intact developing brain are largely unknown. Here, we use two-photon Ca\(^{2+}\) imaging to comprehensively map the developmental trajectories of spontaneous network activity in the hippocampal area CA1 of mice in vivo. We unexpectedly find that network burstiness peaks after the developmental emergence of effective synaptic inhibition in the second postnatal week. We demonstrate that the enhanced network burstiness reflects an increased functional coupling of individual neurons to local population activity. However, pairwise neuronal correlations are low, and network bursts (NBs) recruit CA1 pyramidal cells in a virtually random manner. Using a dynamic systems modeling approach, we reconcile these experimental findings and identify network bi-stability as a potential regime underlying network burstiness at this age. Our analyses reveal an important role of synaptic input characteristics and network instability dynamics for NB generation. Collectively, our data suggest a mechanism, whereby developing CA1 performs extensive input-discrimination learning prior to the onset of environmental exploration.},
  language  = {en}
}
@article{RauschenbergerPiroKasaragodetal.2023,
  author    = {Rauschenberger, Vera and Piro, Inken and Kasaragod, Vikram Babu and H{\"o}rlin, Verena and Eckes, Anna-Lena and Kluck, Christoph J. and Schindelin, Hermann and Meinck, Hans-Michael and Wickel, Jonathan and Geis, Christian and T{\"u}z{\"u}n, Erdem and Doppler, Kathrin and Sommer, Claudia and Villmann, Carmen},
  title     = {Glycine receptor autoantibody binding to the extracellular domain is independent from receptor glycosylation},
  series = {Frontiers in Molecular Neuroscience},
  volume    = {16},
  journal   = {Frontiers in Molecular Neuroscience},
  doi       = {10.3389/fnmol.2023.1089101},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304206},
  year      = {2023},
  abstract  = {Glycine receptor (GlyR) autoantibodies are associated with stiff-person syndrome and the life-threatening progressive encephalomyelitis with rigidity and myoclonus in children and adults. Patient histories show variability in symptoms and responses to therapeutic treatments. A better understanding of the autoantibody pathology is required to develop improved therapeutic strategies. So far, the underlying molecular pathomechanisms include enhanced receptor internalization and direct receptor blocking altering GlyR function. A common epitope of autoantibodies against the GlyRα1 has been previously defined to residues 1A-33G at the N-terminus of the mature GlyR extracellular domain. However, if other autoantibody binding sites exist or additional GlyR residues are involved in autoantibody binding is yet unknown. The present study investigates the importance of receptor glycosylation for binding of anti-GlyR autoantibodies. The glycine receptor α1 harbors only one glycosylation site at the amino acid residue asparagine 38 localized in close vicinity to the identified common autoantibody epitope. First, non-glycosylated GlyRs were characterized using protein biochemical approaches as well as electrophysiological recordings and molecular modeling. Molecular modeling of non-glycosylated GlyRα1 did not show major structural alterations. Moreover, non-glycosylation of the GlyRα1N38Q did not prevent the receptor from surface expression. At the functional level, the non-glycosylated GlyR demonstrated reduced glycine potency, but patient GlyR autoantibodies still bound to the surface-expressed non-glycosylated receptor protein in living cells. Efficient adsorption of GlyR autoantibodies from patient samples was possible by binding to native glycosylated and non-glycosylated GlyRα1 expressed in living not fixed transfected HEK293 cells. Binding of patient-derived GlyR autoantibodies to the non-glycosylated GlyRα1 offered the possibility to use purified non-glycosylated GlyR extracellular domain constructs coated on ELISA plates and use them as a fast screening readout for the presence of GlyR autoantibodies in patient serum samples. Following successful adsorption of patient autoantibodies by GlyR ECDs, binding to primary motoneurons and transfected cells was absent. Our results indicate that the glycine receptor autoantibody binding is independent of the receptor's glycosylation state. Purified non-glycosylated receptor domains harbouring the autoantibody epitope thus provide, an additional reliable experimental tool besides binding to native receptors in cell-based assays for detection of autoantibody presence in patient sera.},
  language  = {en}
}