@phdthesis{Karl2017,
  author    = {Karl, Franziska},
  title     = {The role of miR-21 in the pathophysiology of neuropathic pain using the model of B7-H1 knockout mice},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-156004},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2017},
  abstract  = {The impact of microRNA (miRNA) as key players in the regulation of immune and neuronal gene expression and their role as master switches in the pathophysiology of neuropathic pain is increasingly recognized. miR-21 is a promising candidate that could be linked to the immune and the nociceptive system. To further investigate the pathophysiological role of miR-21 in neuropathic pain, we assesed mice deficient of B7 homolog 1 (B7-H1 ko), a protein with suppressive effect on inflammatory responses. B7-H1 ko mice and wildtype littermates (WT) of three different age-groups, young (8 weeks), middle-aged (6 months), and old (12 months) received a spared nerve injury (SNI). Thermal withdrawal latencies and mechanical withdrawal thresholds were determined. Further, we investigated anxiety-, depression-like and cognitive behavior. Quantitative real time PCR was used to determine miR-21 relative expression in peripheral nerves, dorsal root ganglia and white blood cells (WBC) at distinct time points after SNI. Na{\"i}ve B7-H1 ko mice showed mechanical hyposensitivity with increasing age. Young and middle-aged B7-H1 ko mice displayed lower mechanical withdrawal thresholds compared to WT mice. From day three after SNI both genotypes developed mechanical and heat hypersensitivity, without intergroup differences. As supported by the results of three behavioral tests, no relevant differences were found for anxiety-like behavior after SNI in B7-H1 ko and WT mice. Also, there was no indication of depression-like behavior after SNI or any effect of SNI on cognition in both genotypes. The injured nerves of B7-H1 ko and WT mice showed higher miR-21 expression and invasion of macrophages and T cells 7 days after SNI without intergroup differences. Perineurial miR-21 inhibitor injection reversed SNI-induced mechanical and heat hypersensitivity in old B7-H1 ko and WT mice. This study reveals that reduced mechanical thresholds and heat withdrawal latencies are associated with miR-21 induction in the tibial and common peroneal nerve after SNI, which can be reversed by perineurial injection of a miR-21 inhibitor. Contrary to expectations, miR-21 expression levels were not higher in B7-H1 ko compared to WT mice. Thus, the B7-H1 ko mouse may be of minor importance for the study of miR-21 related pain. However, these results spot the contribution of miR-21 in the pathophysiology of neuropathic pain and emphasize the crucial role of miRNA in the regulation of neuronal and immune circuits that contribute to neuropathic pain.},
  subject      = {neuropathic pain},
  language  = {en}
}
@phdthesis{Panjwani2015,
  author    = {Panjwani, Priyadarshini},
  title     = {Induction, Imaging, Histo-morphological and Molecular Characterization of Myocarditis in the Rat to Explore Novel Diagnostic Strategies for the Detection of Myocardial Inflammation},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122469},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Fulminant myocarditis is rare but a potentially life-threatening disease. Acute or mild myocarditis following acute ischemia is generally associated with a profound activation of the host's immune system. On one hand this is mandatory to protect the host's heart by fighting the invading agents (i.e., bacteria, viruses or other microbial agents) and/or to induce healing and repair processes in the damaged myocardium. On other hand, uncontrolled activation of the immune system may result in the generation of auto-reactive (not always beneficial) immune cells. Myocarditis or inflammatory cardiomyopathy is characterized by focal or diffuse infiltrates, myocyte necrosis and/or apoptosis and subsequent fibrotic replacement of the heart muscle. In humans, about 30\% of the myocarditis-patients develop dilated cardiomyopathy. As the clinical picture of myocarditis is multifaceted, it is difficult to diagnose the disease. Therefore, the main goal of the present work was to test and further develop novel non-invasive methods for the detection of myocardial inflammation by employing both contrast enhanced MRI techniques as well as novel nuclear tracers that are suitable for in vivo PET/ SPECT imaging. As a part of this thesis, a pre-clinical animal model was successfully established by immunizing female Lewis rats with whole-porcine cardiac myosin (CM). Induction of Experimental Autoimmune Myocarditis (EAM) is considered successful when anti-myosin antibody titers are increased more than 100-fold over control animals and pericardial effusion develops. In addition, cardiac tissues from EAM-rats versus controls were analyzed for the expression of various pro-inflammatory and fibrosis markers. To further exploit non-invasive MRI techniques for the detection of myocarditis, our EAM-rats were injected either with (1) ultra-small Paramagnetic iron oxide particles (USPIO's; Feraheme®), allowing for in vivo imaging , (2) micron sized paramagnetic iron oxide particles (MPIO) for ex vivo inflammatory cell-tracking by cMRI, or (3) with different radioactive nuclear tracers (67gallium citrate, 68gallium-labeled somatostatin analogue, and 68gallium-labeled cyclic RGD-peptide) which in the present work have been employed for autoradiographic imaging, but in principle are also suitable for in vivo nuclear imaging (PET/SPECT). In order to compare imaging results with histology, consecutive heart sections were stained with hematoxylin \& eosin (HE, for cell infiltrates) and Masson Goldner trichrome (MGT, for fibrosis); in addition, immuno-stainings were performed with anti-CD68 (macrophages), anti-SSRT2A (somatostatin receptor type 2A), anti-CD61 (β3-integrins) and anti-CD31 (platelet endothelial cell adhesion molecule 1). Sera from immunized rats strongly reacted with cardiac myosin. In immunized rats, echocardiography and subsequent MRI revealed huge amounts of pericardial effusion (days 18-21). Analysis of the kinetics of myocardial infiltrates revealed maximal macrophage invasion between days 14 and 28. Disappearance of macrophages resulted in replacement-fibrosis in formerly cell-infiltrated myocardial areas. This finding was confirmed by the time-dependent differential expression of corresponding cytokines in the myocardium. Immunized animals reacted either with an early or a late pattern of post-inflammation fibrosis. Areas with massive cellular infiltrates were easily detectible in autoradiograms showing a high focal uptake of 67gallium-citrate and 68gallium labeled somatostatin analogues (68Ga DOTA-TATE). Myocardium with a loss of cardiomyocytes presented a high uptake of 68gallium labeled cyclic RGD-peptide (68Ga NOTA-RGD). MRI cell tracking experiments with Feraheme® as the contrast-agent were inconclusive; however, strikingly better results were obtained when MPIOs were used as a contrast-agent: histological findings correlated well with in vivo and ex vivo MPIO-enhanced MRI images. Imaging of myocardial inflammatory processes including the kinetics of macrophage invasion after microbial or ischemic damage is still a major challenge in, both animal models and in human patients. By applying a broad panel of biochemical, histological, molecular and imaging methods, we show here that different patterns of reactivity may occur upon induction of myocarditis using one and the same rat strain. In particular, immunized Lewis rats may react either with an early or a late pattern of macrophage invasion and subsequent post-inflammation fibrosis. Imaging results achieved in the acute inflammatory phase of the myocarditis with MPIOs, 67gallium citrate and 68gallium linked to somatostatin will stimulate further development of contrast agents and radioactive-nuclear tracers for the non-invasive detection of acute myocarditis and in the near future perhaps even in human patients.},
  subject      = {Ratte},
  language  = {en}
}
@phdthesis{Leinweber2022,
  author    = {Leinweber, Jonas},
  title     = {Untersuchung zur pathophysiologischen Rolle und therapeutischen Relevanz der neuen Inhibitoren der plasmatischen Blutgerinnung Agaphelin und Ixolaris im experimentellen Schlaganfallmodell der Maus},
  doi       = {10.25972/OPUS-25292},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252921},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {Beim isch{\"a}mischen Schlaganfall f{\"u}hrt ein thrombotischer Verschluss von gehirnversorgenden Arterien zu einer akuten Durchblutungsst{\"o}rung, mit der Folge von neurologischen Defiziten. Prim{\"a}res Therapieziel ist es, diese Blutgerinnsel aufzul{\"o}sen, um die Sauerstoffversorgung des Gehirns wiederherzustellen und den isch{\"a}mischen Hirnschaden zu begrenzen. Dazu stehen die intraven{\"o}sen Thrombolyse mit rt-PA (rekombinanter Gewebe-Plasminogen-Aktivator) sowie die endovaskul{\"a}re mechanische Thrombektomie zur Verf{\"u}gung. H{\"a}ufig kann ein Schlaganfall, trotz erfolgreicher Rekanalisation der Gef{\"a}ße, zu einer weiteren Gr{\"o}ßenzunahme des Infarktes und neurologischen Defiziten bei den Patienten f{\"u}hren. Diese Gr{\"o}ßenzunahme beruht zum einen auf einem sich entwickelnden Hirn{\"o}dem und zum anderen auf entz{\"u}ndlichen Prozessen. Zahlreiche Hinweise deuten darauf hin, dass der Schlaganfall ein Zusammenspiel aus thrombotischen und entz{\"u}ndlichen Ereignissen ist, ein Ph{\"a}nomen, das als Thromboinflammation bezeichnet wird. Aufgrund der begrenzten Behandlungsm{\"o}glichkeiten ist die Entwicklung neuer Therapieans{\"a}tze f{\"u}r den isch{\"a}mischen Schlaganfall besonders wichtig. Agaphelin und Ixolaris sind Proteine aus den Speicheldr{\"u}sen von H{\"a}matophagen, f{\"u}r welche in fr{\"u}heren Studien eine starke antithrombotische Wirkung bei gleichzeitig geringem Blutungsrisiko nachgewiesen wurde. Diese m{\"o}glichen antithrombotischen Effekte wurden in dieser Studie im Hinblick auf ihre Wirksamkeit und Sicherheit im Mausmodell der zerebralen Isch{\"a}mie untersucht. Die Behandlung der M{\"a}use mit Agaphelin 1 Stunde nach transienter Okklusion der Arteria cerebri media (tMCAO) f{\"u}hrte zu kleineren Schlaganfallvolumina und geringeren neurologischen Defiziten an Tag 1 nach dem Schlaganfall. Die Mortalit{\"a}t der M{\"a}use war bis Tag 7 deutlich gesunken. Aus klinischer Sicht ist ebenfalls relevant, dass der starke antithrombotische Effekt von Agaphelin im Mausmodell nicht mit einem erh{\"o}hten Risiko f{\"u}r intrazerebrale Blutungen einherging. Diesem protektiven Effekt von Agaphelin lagen eine verminderte intrazerebrale Thrombusbildung, eine abgeschw{\"a}chte Entz{\"u}ndungsantwort und eine Stabilisierung der Blut-Hirn-Schranke sowie eine Reduzierung der Apoptose zugrunde. Nach der Gabe von Ixolaris 1 Stunde nach tMCAO waren zwar signifikant geringere Infarktgr{\"o}ßen messbar, diese f{\"u}hrten allerdings nicht zu einer Verbesserung der neurologischen Defizite. Zudem verursachte die Gabe von Ixolaris schon 24 Stunden nach tMCAO erhebliche intrazerebrale Blutungen und auch die Mortalit{\"a}t der M{\"a}use war zu diesem Zeitpunkt bereits erh{\"o}ht. Aufgrund dieser massiven Nebenwirkungen scheint Ixolaris kein geeigneter Kandidat f{\"u}r eine humane Anwendung zu sein. Bei Agaphelin hingegen k{\"o}nnte es sich um einen vielversprechenden Kandidaten f{\"u}r die Behandlung des isch{\"a}mischen Schlaganfalls handeln. Vor einer m{\"o}glichen Testung von Agaphelin in klinischen Studien, sind weitere translationale Untersuchungen notwendig, um ein noch pr{\"a}ziseres Verst{\"a}ndnis f{\"u}r die Wirksamkeit und Sicherheit von Agaphelin zu gewinnen. Insgesamt stellt die Hemmung thromboinflammatorischer Prozesse, ohne eine Erh{\"o}hung der Blutungskomplikationen, eine vielversprechende Option zur Behandlung des isch{\"a}mischen Schlaganfalls dar.},
  subject      = {Schlaganfall},
  language  = {de}
}
@phdthesis{Krampert2024,
  author    = {Krampert, Laura},
  title     = {Dynamics of cardiac neutrophil diversity in murine myocardial infarction},
  doi       = {10.25972/OPUS-34957},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-349576},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {After myocardial infarction, an inflammatory response is induced characterized by a sterile inflammation, followed by a reparative phase in order to induce cardiac healing. Neutrophils are the first immune cells that enter the ischemic tissue. Neutrophils have various functions in the ischemic heart, such as phagocytosis, production of reactive oxygen species or release of granule components. These functions can not only directly damage cardiac tissue, but are also necessary for initiating reparative effects in post-ischemic healing, indicating a dual role of neutrophils in cardiac healing after infarction. In recent years, evidence has been growing that neutrophils show phenotypic and functional differences in distinct homeostatic and pathogenic settings. Preliminary data of my working group using single-cell RNA-sequencing revealed the time- dependent heterogeneity of neutrophils, with different populations showing distinct gene expression profiles in ischemic hearts of mice, including the time-dependent appearance of a SiglecFhigh neutrophil population. To better understand the dynamics of neutrophil heterogeneity in the ischemic heart, my work aimed to validate previous findings at the protein level, as well as to investigate whether the distinct neutrophil populations show functional differences. Furthermore, in vivo depletion experiments were performed in order to modulate circulating neutrophil levels. Hearts, blood, bone marrow and spleens were processed and analyzed from mice after 1 day and 3 days after the onset of cardiac ischemia and analyzed using flow cytometry. Results showed that the majority of cardiac neutrophils isolated at day 3 after myocardial infarction were SiglecFhigh, whereas nearly no SiglecFhigh neutrophils could be isolated from ischemic hearts at day 1 after myocardial infarction. No SiglecFhigh neutrophils could be found in the blood, spleen and bone marrow either after 1 day or 3 days after myocardial infarction, indicating that the SiglecFhigh state of neutrophils is unique to the ischemic cardiac tissue. When I compared SiglecFhigh and SiglecFlow neutrophils regarding their phagocytosis activity and ROS production, SiglecFhigh neutrophils showed a higher phagocytosis ability than their SiglecFlow counterparts, as well as higher ROS production capacity. In vivo depletion experiments could not achieve successful and efficient depletion of cardiac neutrophils either 1 day or 3 days after myocardial infarction, but led to a shift of a higher percentage of SiglecFhigh expressing neutrophils in the depletion group. Bone marrow neutrophil levels only showed partial depletion at day 3 after MI. Regarding blood neutrophils, depletion efficiently reduced circulating neutrophils at both time points, 1 and 3 days after MI. To summarize, this work showed the time-dependent presence of different neutrophil states in the ischemic heart. The main population of neutrophils isolated 3 days after MI showed a high expression of SiglecF, a unique state that could not be detected at different time points or other organs. These SiglecFhigh neutrophils showed functional differences regarding their phagocytosis ability and ROS production. Further investigation is needed to reveal what role these SiglecFhigh neutrophils could play within the ischemic heart. To better target neutrophil depletion in vivo, more efficient or different anti-neutrophil strategies are needed.},
  subject      = {Neutrophiler Granulozyt},
  language  = {en}
}