Post-mortem Untersuchungen der Tau-Pathologie in den Augenmuskelkernen von Fällen mit progressiver supranukleärer Blickparese

A good knowledge of the crucial brainstem areas and pathways for generating saccadic eye movements forms the basis for the work presented here. The findings are expected to contribute to the understanding of propagation pathways in tauopathies, particularly progressive supranuclear palsy (PSP). In this post-mortem pilot project, it was investigated whether a correlation exists between the type and severity of eye movement disorders and the degeneration of the motoneurons of the extraocular muscles in PSP patients. For this purpose, eight neuropathologically confirmed PSP cases with existing clinical symptoms and three control cases were examined in the oculomotor nucleus (nIII), trochlear nucleus (nIV), abducens nucleus (nVI), central caudal nucleus (CCN), and Edinger-Westphal nucleus central projecting population (EWcp) by immunostaining with mouse anti-human PHF-Tau (AT8) and hemalaun counterstaining. The eight PSP cases were classified into four stages of disease. Stage I shows no saccade deficits. Stage II is characterized by the presence of vertical gaze palsies. In stage III, the vertical gaze palsies are accompanied by slowed horizontal saccades, and in stage IV, complete gaze palsy in all directions is present. The vestibulo-ocular reflex (VOR) was still present in stages I-III and could not be elicited in stage IV. After immunohistochemical staining, the sections were digitized with a slide scanner at 20x magnification, viewed with the "Panoramic viewer software", evaluated and then analyzed. With the help of the software HistoQuant, fibers and glial cells could be recorded in addition to neurons. A semiquantitative evaluation was also performed in the premotor gaze centers for horizontal and vertical saccades, the paramediane pontine formatio reticularis (PPRF) and rostral interstitial nucleus of medial longitudinal fasciculus (RIMLF), respectively. In the oculomotor nuclei, there was essentially an increase in AT8 immunostaining from stage I to IV. There was no difference between the motor neurons responsible for horizontal or vertical gaze directions, respectively. Comparing the two premotor gaze centers, the RIMLF was slightly more affected than the PPRF; even at low clinical expression (stage I) a considerable AT8 immunoreactivity was present in the premotor centers. Degeneration of premotor areas, such as RIMLF and PPRF, is most likely to be responsible for the observed eye movement disorders in PSP. This work demonstrated that tau pathology can be found within the oculomotor circuit up to the level of motor nuclei supporting and is associated with the severity of the oculomotor symptoms. Thereby these findings support a hypothesis that PSP pathology spreads along neuronal connections. Further studies are needed to better understand the spread of PSP-pathology and to obtain further diagnostic and therapeutic targets.Die guten Erkenntnisse über die Bahnen und Hirnstammareale, die zur Generierung von sakkadischen Augenbewegungen wichtig sind, bilden die Grundlage für die hier vorliegende Arbeit. Die Befunde sollen einen Beitrag zum Verständnis für die Ausbreitungswege bei Taupathologien, insbesondere der PSP, liefern. Im Rahmen dieses Pilotprojekts wurde untersucht, ob eine Korrelation zwischen der Art und Schwere der Augenbewegungsstörungen und der Degeneration der Motoneurone der äußeren Augenmuskeln bei PSP-Erkrankten existiert. Hierzu wurden acht neuropathologisch bestätigte PSP-Fälle mit vorliegender klinischer Symptomatik und drei Kontrollfälle in den Arealen nIII, nIV, nVI, CCN und EWcp mittels immunhistochemischer Maus anti-humanes PHF-Tau Färbung (AT8) und Hämalaun-Gegenfärbung untersucht. Die acht PSP-Fälle wurden in vier Krankheitsstadien eingeteilt. Stadium I zeigt keine Sakkadendefizite. Stadium II ist durch das Auftreten von vertikalen Blickparesen gekennzeichnet. Im Stadium III sind die vertikalen Blickparesen von verlangsamten horizontalen Sakkaden begleitet und im Stadium IV ist eine komplette Blickparese in alle Richtungen manifest. Der VOR war in den Stadien I-III noch vorhanden und ließ sich in Stadium IV nicht mehr auslösen. Nach der immunhistochemischen Färbung wurden die Schnitte eingescannt (Slide-Scanner Mirax MIDI BF), bei 20-facher Vergrößerung digitalisiert, mit der „Viewer-Software Panoramic“ gesichtet, ausgewertet und analysiert. Mit Hilfe von HistoQuant konnten neben den Neuronen auch Fasern und Gliazellen erfasst werden. Eine semiquantitative Auswertung erfolgte zudem in den übergeordneten Zentren. In den okulomotorischen Kernen zeigte sich im Wesentlichen eine zunehmende AT8-Immunreaktivität von Stadium I bis IV. Ein Unterschied zwischen den Motoneuronen, die für die horizontalen bzw. vertikalen Blickrichtungen verantwortlich sind, zeigte sich nicht. Im Vergleich der beiden übergeordneten Zentren, war der RIMLF geringfügig stärker betroffen als die PPRF und es bestand bereits bei geringer klinischer Ausprägung (Stadium I) eine AT8-Immunreaktivität in den übergeordneten Zentren. Für die beobachteten Augenbewegungs-störungen bei der PSP steht am ehesten die Degeneration der prämotorischen Areale, wie RIMLF und PPRF, im Vordergrund. Die vorliegende Arbeit konnte zeigen, dass die Tau-Pathologie bis in die motorischen Kerne des okulomotorischen Systems gefunden werden kann und mit der Schwere der Symptomatik in Zusammenhang steht. Es müssen noch weitere Studien erfolgen um die Ausbreitung der PSP besser zu verstehen und um weitere diagnostische und therapeutische Angriffsziele zu erhalten

Humoral Response to SARS-CoV-2 Antigen in Patients Treated with Monoclonal Anti-CD20 Antibodies: It Is Not All about B Cell Recovery

Anti-CD20 therapies decrease the humoral response to SARS-CoV-2 immunization. We aimed to determine the extent of the humoral response to SARS-CoV-2 antigens in correlation with peripheral B-cell dynamics among patients with central nervous system inflammatory disorders treated with anti-CD20 medications. We retrospectively included patients receiving anti-CD20 therapy after antigen contact who were divided into responders (>7 binding antibody units (BAU)/mL) and non-responders (<7 BAU/mL). In participants with first antigen contact prior to therapy, we investigated the recall response elicited once under treatment. We included 80 patients (responders n = 34, non-responders n = 37, recall cohort n = 9). The B-cell counts among responders were significantly higher compared to non-responders (mean 1012 cells/µL ± SD 105 vs. mean 17 cells/µL ± SD 47; p < 0.001). Despite very low B-cell counts (mean 9 cells/µL ± SD 20), humoral response was preserved among the recall cohort (mean 1653 BAU/mL ± SD 2250.1) and did not differ significantly from responders (mean 735 BAU/mL ± SD 1529.9; p = 0.14). Our data suggest that peripheral B cells are required to generate antibodies to neo-antigens but not for a recall response during anti-CD20 therapy. Evaluation of B-cell counts and pre-existing SARS-CoV-2 antibodies might serve as biomarkers for estimating the immune competence to mount a humoral response to SARS-CoV-2 antigens

Comparison of Organic and Conventional Beef-Suckler Farms in Germany

This study aims to compare conventional and organic farms with beef-suckler herds. Addresses were collected mainly by contacting breeding associations and farmers' magazines. 216 questionnaires were evaluated (34.1% of them organic). Beef-suckler production in Germany is an extensive production system (small farms, small herd sizes, high percentage of grassland, low soil points, etc.). 39% of farms had to fulfil special regulations for extensive grassland production and 43% carried out landscape conservation measures. Farmers specialize in beef-suckler production. 60% of them are part-time farmers. Beef production amounts to two thirds of their agricultural income. Most farmers keep only beef cattle on the farms. Other farm animals are kept in small stock sizes. This study has found only a few differences between conventional and organic farms. Organic farmers more often keep breeds of low intensity but more of them use direct marketing channels. On organic farms cows more frequently stay outside all year. Animal performances were the same in both production systems

Clinical Challenges in a 49-Year-Old Patient with Severe Tick-Borne Myeloradiculitis Despite Complete Active Vaccination

Vaccination is an effective means to prevent infectious diseases including tick-borne encephalitis (TBE), an emerging Flavivirus infection. There is, however, only limited knowledge about risk of vaccination failure, the disease course and the challenges for work-up and care. Of note, there is evidence that patients with breakthrough disease experience a more severe disease course. We report the case of a previously healthy 49-year-old woman who developed severe myeloradiculitis caused by the TBE virus despite receiving a complete cycle of primary immunization and booster vaccinations within the recommended timeframe. The disease course was characterized by progressive tetraparesis, pain and bladder dysfunction and necessitated intensive care unit admission (ICU) and the escalation of pain management. This case raises awareness for the recognition of breakthrough disease in younger patients and reinforces the need to develop measures to identify patients with insufficient protection

Innate Immune Signaling and Role of Glial Cells in Herpes Simplex Virus- and Rabies Virus-Induced Encephalitis

The environment of the central nervous system (CNS) represents a double-edged sword in the context of viral infections. On the one hand, the infectious route for viral pathogens is restricted via neuroprotective barriers; on the other hand, viruses benefit from the immunologically quiescent neural environment after CNS entry. Both the herpes simplex virus (HSV) and the rabies virus (RABV) bypass the neuroprotective blood–brain barrier (BBB) and successfully enter the CNS parenchyma via nerve endings. Despite the differences in the molecular nature of both viruses, each virus uses retrograde transport along peripheral nerves to reach the human CNS. Once inside the CNS parenchyma, HSV infection results in severe acute inflammation, necrosis, and hemorrhaging, while RABV preserves the intact neuronal network by inhibiting apoptosis and limiting inflammation. During RABV neuroinvasion, surveilling glial cells fail to generate a sufficient type I interferon (IFN) response, enabling RABV to replicate undetected, ultimately leading to its fatal outcome. To date, we do not fully understand the molecular mechanisms underlying the activation or suppression of the host inflammatory responses of surveilling glial cells, which present important pathways shaping viral pathogenesis and clinical outcome in viral encephalitis. Here, we compare the innate immune responses of glial cells in RABV- and HSV-infected CNS, highlighting different viral strategies of neuroprotection or Neuroinflamm. in the context of viral encephalitis

Vitamin D Supplementation in Multiple Sclerosis: A Critical Analysis of Potentials and Threats

Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system (CNS). In recent years, vitamin D has gained attention, as low serum levels are suspected to increase the risk for MS. Cholecalciferol supplementation has been tested in several clinical trials, since hypovitaminosis D was linked to higher disease activity and may even play a role in long-term outcome. Here, we review the current understanding of the molecular effects of vitamin D beyond calcium homeostasis, the potential beneficial action in MS and hazards including complications of chronic and high-dose therapy. In clinical trials, doses of up to 40,000 IU/day were tested and appeared safe as add-on therapy for short-term periods. A recent meta-analysis of a randomized, double-blind, placebo-controlled clinical trial investigating vitamin D as add-on therapy in MS, however, suggested that vitamin D had no therapeutic effect on disability or relapse rate. We recognize a knowledge gap for chronic and high-dose therapy, which can lead to life-threatening complications related to vitamin D toxicity including renal failure, cardiac arrythmia and status epilepticus. Moreover, vitamin D toxicity may manifest as fatigue, muscle weakness or urinary dysfunction, which may mimic the natural course of progressive MS. Given these limitations, vitamin D supplementation in MS is a sensitive task which needs to be supervised by physicians. While there is strong evidence for vitamin D deficiency and the development of MS, the risk-benefit profile of dosage and duration of add-on supplementation needs to be further clarified

Germline mutation within COL2A1 associated with lethal chondrodysplasia in a polled Holstein family

Abstract Background The bulldog calf syndrome is a lethal form of the inherited congenital chondrodysplasias. Among the progeny of the polled Holstein bull Energy P cases of lethal chondrodysplasia were observed. Pedigrees of the cases and the frequency of 3/8 cases among the offspring of Energy P at our teaching and experimental farm Ruthe (LuFG Ruthe) supported the assumption of a germline mutation with a mosaic of normal and defective sperm. Results All three malformed calves were examined using necropsy, histopathology and computed tomography scanning. The phenotypic appearance of the affected calves was highly similar; they presented with severe disproportionate dwarfism and reduced body weight. The syndrome was characterized by brachygnathia superior, bilateral palatoschisis, shortening and compression of the body due to malformed vertebrae, in their size reduced and malformed ribs and reduced length of the long bones of the limbs. The bones had small irregular diaphyses and enlarged epiphyses. Whole genome sequencing of one bulldog calf, sperm of its sire Energy P and a normal progeny of Energy P identified a deleterious missense mutation (g.32476082G > A, c.2986G > A, ss2019324576) within COL2A1 on bovine chromosome (BTA) 5. Sanger sequencing confirmed the ss2019324576 variant in the affected calves and sperm of Energy P. This mutation is located within the collagen triple helix repeat and causes an exchange of glycine to serine (p.996G > S) in COL2A1. This private single nucleotide variant (SNV) was present as a gonadal mosaic in sperm of the bull. All affected calves were in a heterozygous state whereas normal half-siblings and all dams of the progeny from Energy P were missing this SNV. Validation in polled Holstein bulls and normal Holstein calves randomly sampled from several herds and from the LuFG Ruthe confirmed this SNV as private. Conclusions The identified spontaneous missense mutation within COL2A1 is most likely the cause of lethal chondrodysplasia in the progeny of Energy P through a dominant negative effect. This example suggests that it would be beneficial to conduct whole genome sequencing of sperm from bulls widely used in artificial insemination in order to detect germline mosaicism

Cladribine Alters Immune Cell Surface Molecules for Adhesion and Costimulation: Further Insights to the Mode of Action in Multiple Sclerosis

Cladribine (CLAD) is a deoxyadenosine analogue prodrug which is given in multiple sclerosis (MS) as two short oral treatment courses 12 months apart. Reconstitution of adaptive immune function following selective immune cell depletion is the presumed mode of action. In this exploratory study, we investigated the impact of CLAD tablets on immune cell surface molecules for adhesion (CAMs) and costimulation (CoSs) in people with MS (pwMS). We studied 18 pwMS who started treatment with CLAD and 10 healthy controls (HCs). Peripheral blood mononuclear cells were collected at baseline and every 3 months throughout a 24-month period. We analysed ICAM-1, LFA-1, CD28, HLADR, CD154, CD44, VLA-4 (CD49d/CD29), PSGL-1 and PD-1 with regard to their expression on B and T cells (T helper (Th) and cytotoxic T cells (cT)) and surface density (mean fluorescence intensity, MFI) by flow cytometry. The targeted analysis of CAM and CoS on the surface of immune cells in pwMS revealed a higher percentage of ICAM-1 (B cells, Th, cT), LFA-1 (B cells, cT), HLADR (B cells, cT), CD28 (cT) and CD154 (Th). In pwMS, we found lower frequencies of Th and cT cells expressing PSGL-1 and B cells for the inhibitory signal PD-1, whereas the surface expression of LFA-1 on cT and of HLADR on B cells was denser. Twenty-four months after the first CLAD cycle, the frequencies of B cells expressing CD44, CD29 and CD49d were lower compared with the baseline, together with decreased densities of ICAM-1, CD44 and HLADR. The rate of CD154 expressing Th cells dropped at 12 months. For cT, no changes were seen for frequency or density. Immune reconstitution by oral CLAD was associated with modification of the pro-migratory and -inflammatory surface patterns of CAMs and CoSs in immune cell subsets. This observation pertains primarily to B cells, which are key cells underlying MS pathogenesis