@phdthesis{Fischer2008,
  author    = {Fischer, Stefan Martin},
  title     = {Regulation and functional consequences of MCP-1 expression in a model of Charcot-Marie-Tooth 1B disease},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-29189},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2008},
  abstract  = {Charcot-Marie-Tooth 1B (CMT1B) is a progressive inherited demyelinating disease of human peripheral nervous system leading to sensory and/or motor function disability and is caused by mutations in the P0 gene. Mice heterozygously deficient for P0 (P0+/-) are an adequate model of this human disorder showing myelin degeneration, formation of onion bulbs, remyelination and a reduced motor conduction velocity of around 30m/s similar to patients. Previously, it had been shown that T-lymphocytes and macrophages play a crucial role during pathogenesis in peripheral nerves of P0+/- mice. Both, T-lymphocytes and macrophages increase in number in the endoneurium and deletion of T-lymphocytes or deletion of a macrophage-directed cytokine ameliorates the disease. In this study the monocyte chemoattractant protein-1 (MCP-1) was identified as an early regulated cytokine before onset of disease is visible at the age of six months. MCP-1 mRNA and protein expression could be detected in femoral quadriceps and sciatic nerves of P0+/- mice already at the age of one month but not in cutaneous saphenous nerves which are never affected by the disease. MCP-1 was shown to be expressed by Schwann cells and to mediate the immigration of immune cells into peripheral nerves. Deletion of MCP-1 in P0+/- mice accomplished by crossbreeding P0 and MCP-1 deficient mice revealed a substantial reduction of immune cells in peripheral nerves of P0+/-/MCP-1+/- and P0+/-/MCP-1-/- mice at the age of six months. In twelve months old mice reduction of immune cells in peripheral nerves is accompanied by amelioration of demyelinating disease in P0+/-/MCP-1+/- and aggravation of demyelinating disease in lumbar ventral roots of P0+/ /MCP-1-/- mice in comparison to P0+/ /MCP 1+/+ mice. Furthermore, activation of the MEK1/2-ERK1/2 signalling cascade could be demonstrated to take place in Schwann cells of affected peripheral nerves of P0+/- mice overlapping temporarily and spatially with MCP-1 expression. An animal experiment using a MEK1/2-inhibitor in vivo, CI-1040, revealed that upon reduction of ERK1/2 phosphorylation MCP-1 mRNA expression is diminished suggesting that the activation of the MEK1/2-ERK1/2 signalling cascade is necessary for MCP-1 expression. Additionally, peripheral nerves of P0+/- mice showing reduced ERK1/2 phosphorylation and MCP-1 mRNA expression also show reduced numbers of macrophages in the endoneurium. This study shows a molecular link between a Schwann cell based mutation and immune cell function. Inhibition of the identified signalling cascade might be a putative target for therapeutic approaches.},
  subject      = {Schwann-Zelle},
  language  = {en}
}
@phdthesis{Klein2015,
  author    = {Klein, Dennis},
  title     = {The pathogenic role of endogenous antibodies in a mouse model for Charcot-Marie-Tooth 1B neuropathy},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121941},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Charcot-Marie-Tooth (CMT) type 1 neuropathies are a genetically heterogeneous group of non-treatable inherited disorders affecting the peripheral nervous system that lead to sensory and motor dysfunction. Secondary low grade inflammation, implicating the innate and adaptive immune system, could previously be identified as a substantial disease modifier in two mouse models for CMT1, CMT1B and 1X, respectively. However, the exact mechanism how the adaptive immune system contributes to disease pathogenesis is not completely understood. Based on observations that the accumulation of endogenous antibodies to myelin components is important for rapid myelin clearance after nerve injury during Wallerian degeneration, a possibly similar mechanism was considered for endogenous antibodies as disease amplifier in mice heterozygously deficient for P0 (P0het), mimicking some typical features of CMT1B. In this study an increased antibody deposition was detected in the affected peripheral nerves of P0het myelin mutant mice. By crossbreeding P0het mutants with mice specifically lacking B-lymphocytes, and therefore antibodies (JHD-/-), a decline of endoneurial macrophages together with a substantially ameliorated demyelination could be demonstrated in 6-month-old mutant mice. Moreover, reconstitution with murine IgGs reverted the neuropathic phenotype, substantiating that endogenous antibodies are potentially pathogenic at this early stage of disease. Unexpectedly, in 12-months-old P0het mutants, JHD deficiency resulted in disease aggravation accompanied by an increased inflammatory reaction and M2-polarized macrophage response. These observations suggest that in a mouse model for CMT1B, the lack of endogenous antibodies has a dichotomous effect: ameliorating early macrophage-mediated demyelination, as opposed to increasing inflammatory reactions leading to disease aggravation at older ages.},
  subject      = {Maus},
  language  = {en}
}
@phdthesis{Ostertag2023,
  author    = {Ostertag, Viktoria Charlotte Caroline},
  title     = {Pr{\"a}ventive und therapeutische Behandlung mit einem CSF-1-Rezeptorinhibitor bei verschiedenen Charcot-Marie-Tooth Mausmodellen},
  doi       = {10.25972/OPUS-30852},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-308528},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2023},
  abstract  = {Die Charcot-Marie-Tooth-Neuropathie umfasst eine heterogene Gruppe von erblichen unter anderem demyelinisierenden Erkrankungen des peripheren Nervensystems. Trotz ihrer hohen Pr{\"a}valenz von 1:2.500 gibt es bis dato keine kausalen Therapiem{\"o}glichkeiten. Durch den progressiven Krankheitsverlauf wird die Lebensqualit{\"a}t der Patienten stetig gemindert; der fortschreitende Verlust der Muskelkraft und St{\"o}rungen des Gangbildes sind besonders belastend. Urs{\"a}chlich f{\"u}r die CMT1-Neuropathie sind unter anderem Mutationen in Genen, die f{\"u}r Molek{\"u}le des Myelins von Schwannzellen codieren. Diese Mutationen f{\"u}hren zu einer verminderten Stabilit{\"a}t und Funktion des Myelins und so letzten Endes zu einer Demyelinisierung und axonalen Sch{\"a}digung der peripheren Nerven. Weitere Studien in CMT1-Mausmodellen zeigten jedoch, dass nicht nur die verringerte Myelinstabilit{\"a}t sondern auch eine durch das Immunsystem vermittelte geringgradige Entz{\"u}ndungsreaktion f{\"u}r die Symptome urs{\"a}chlich sein k{\"o}nnte. Hier spielen vor allem Makrophagen eine zentrale Rolle. Das Zytokin CSF-1 aktiviert die Makrophagen und verursacht so eine Demyelinisierung der peripheren Nerven. In P0het und Cx32def Mausmodellen konnte nachgewiesen werden, dass eine medikament{\"o}se Inhibition des CSF-1-Rezeptors an Makrophagen zu einem verbesserten Nervph{\"a}notypen und einer deutlichen Abmilderung des Krankheitsbildes f{\"u}hrte. In dieser Arbeit wurden in P0het und Cx32def Mausmodellen weiterf{\"u}hrende Behandlungsstudien mit einem CSF-1-RI durchgef{\"u}hrt, die untersuchen, zu welchem Zeitpunkt innerhalb des Krankheitsverlaufs (therapeutisch oder pr{\"a}ventiv) eine erfolgreiche Therapie noch m{\"o}glich ist und ob bei einem fr{\"u}heren Beginn eine noch bessere Wirkung erzielt werden kann. Abh{\"a}ngig von den verschiedenen Start- und Endpunkten waren unterschiedliche Ergebnisse zu beobachten: Hinsichtlich der klinischen Parameter wie der Greifkraft und der Anzahl an abnormal innervierten Synapsen zeigten die Tiere im pr{\"a}ventiven Behandlungszweig in beiden Mausmodellen das beste Ergebnis im Vergleich zu den Kontrolltieren. Diese substantielle Verbesserung ließ sich unabh{\"a}ngig von einem Makrophagen-Reflux sogar noch 6 Monate nach Behandlungsabbruch nachweisen. Bez{\"u}glich der endoneuralen Makrophagendepletion war sowohl in den P0het als auch den Cx32def Tieren im pr{\"a}ventiven sowie im therapeutischen Behandlungszweig eine signifikante Verbesserung zu beobachten. Diese Ergebnisse heben ein weiteres Mal die Bedeutung der Makrophagen als Teil einer Entz{\"u}ndungsreaktion in der Pathogenese der CMT1-Neuropathie hervor. Des Weiteren konnte die These gefestigt werden, dass eine Inhibition des CSF-1-Rezeptors zu verbesserten histopathologischen sowie funktionellen Parametern f{\"u}hrt. Um ein gutes Ansprechen auf die Therapie zu erzielen, m{\"u}ssen ein m{\"o}glichst fr{\"u}her Therapiebeginn sowie eine nachhaltige Behandlungsdauer gew{\"a}hrleistet sein.},
  subject      = {Charcot-Marie-Syndrom},
  language  = {de}
}