Publications by authors named "Stefanie Kuerten"

87 Publications

Mice Heterozygous for the Sodium Channel Scn8a (Nav1.6) Have Reduced Inflammatory Responses During EAE and Following LPS Challenge.

Front Immunol 2021 19;12:533423. Epub 2021 Mar 19.

Department of Pathology, Dalhousie University, Halifax, NS, Canada.

Voltage gated sodium (Nav) channels contribute to axonal damage following demyelination in experimental autoimmune encephalomyelitis (EAE), a rodent model of multiple sclerosis (MS). The Nav1.6 isoform has been implicated as a primary contributor in this process. However, the role of Nav1.6 in immune processes, critical to the pathology of both MS and EAE, has not been extensively studied. EAE was induced with myelin oligodendrocyte (MOG) peptide in mice, which have reduced Nav1.6 levels. mice demonstrated improved motor capacity during the recovery and early chronic phases of EAE relative to wild-type animals. In the optic nerve, myeloid cell infiltration and the effects of EAE on the axonal ultrastructure were also significantly reduced in mice. Analysis of innate immune parameters revealed reduced plasma IL-6 levels and decreased percentages of Gr-1/CD11b and Gr-1/CD11b myeloid cells in the blood during the chronic phase of EAE in mice. Elevated levels of the anti-inflammatory cytokines IL-10, IL-13, and TGF-β1 were also observed in the brains of untreated mice. A lipopolysaccharide (LPS) model was used to further evaluate inflammatory responses. mice displayed reduced inflammation in response to LPS challenge. To further evaluate if this was an immune cell-intrinsic difference or the result of changes in the immune or hormonal environment, mast cells were derived from the bone marrow of mice. These mast cells also produced lower levels of IL-6, in response to LPS, compared with those from wild type mice. Our results demonstrate that in addition to its recognized impact on axonal damage, Nav1.6 impacts multiple aspects of the innate inflammatory response.
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http://dx.doi.org/10.3389/fimmu.2021.533423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8017164PMC
March 2021

Murine Esophagus Expresses Glial-Derived Central Nervous System Antigens.

Int J Mol Sci 2021 Mar 22;22(6). Epub 2021 Mar 22.

Institute of Anatomy and Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.

Multiple sclerosis (MS) has been considered to specifically affect the central nervous system (CNS) for a long time. As autonomic dysfunction including dysphagia can occur as accompanying phenomena in patients, the enteric nervous system has been attracting increasing attention over the past years. The aim of this study was to identify glial and myelin markers as potential target structures for autoimmune processes in the esophagus. RT-PCR analysis revealed glial fibrillary acidic protein (GFAP), proteolipid protein (PLP), and myelin basic protein (MBP) expression, but an absence of myelin oligodendrocyte glycoprotein (MOG) in the murine esophagus. Selected immunohistochemistry for GFAP, PLP, and MBP including transgenic mice with cell-type specific expression of PLP and GFAP supported these results by detection of (1) GFAP, PLP, and MBP in Schwann cells in skeletal muscle and esophagus; (2) GFAP, PLP, but no MBP in perisynaptic Schwann cells of skeletal and esophageal motor endplates; (3) GFAP and PLP, but no MBP in glial cells surrounding esophageal myenteric neurons; and (4) PLP, but no GFAP and MBP in enteric glial cells forming a network in the esophagus. Our results pave the way for further investigations regarding the involvement of esophageal glial cells in the pathogenesis of dysphagia in MS.
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http://dx.doi.org/10.3390/ijms22063233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8004938PMC
March 2021

B-Cell Activity Predicts Response to Glatiramer Acetate and Interferon in Relapsing-Remitting Multiple Sclerosis.

Neurol Neuroimmunol Neuroinflamm 2021 05 11;8(3). Epub 2021 Mar 11.

From the Institute of Anatomy and Cell Biology (S.T., D.M.R., S.K.), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Germany; NeuroTransData (S.B., H.D., A.B.), Neuburg an der Donau, Germany; Department of Neurology (T.Z.), Center of Clinical Neuroscience, University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; and Research and Development Department (P.V.L.), Cellular Technology Limited, Shaker Heights, OH.

Objective: We investigated the predictive value of the enzyme-linked immunospot technique (ELISPOT) in identifying patients with relapsing-remitting multiple sclerosis (RRMS) who will respond to treatment with glatiramer acetate (GA) or interferon-β (IFN-β), based on the brain-reactive B-cell activity of peripheral blood cells.

Methods: In this retrospective, cross-sectional, real-world multicenter study, we identified patients with RRMS in the NeuroTransData MS registry and stratified them based on their documented treatment response (relapse-free in the first 12 months of treatment) to GA or IFN-β. The GA group comprised 73 patients who responded to GA and 35 nonresponders. The IFN-β group comprised 62 responders to IFN-β and 37 nonresponders. Patients with previous or current therapy affecting B-cell activity were excluded. We polyclonally stimulated mononuclear cells from peripheral blood samples (collected after participant selection) and investigated brain-reactive B-cell activity after incubation on brain tissue lysate-coated ELISPOT plates. Validity metrics of the ELISPOT testing results were calculated (Python 3.6.8) in relation to the clinical responsiveness in the 2 treatment groups.

Results: The ELISPOT B-cell activity assay showed a sensitivity of 0.74, a specificity of 0.76, a positive predictive value of 0.78, a negative predictive value of 0.28, and a diagnostic OR of 8.99 in predicting clinical response to GA vs IFN-β therapy in patients with RRMS.

Conclusion: Measurement of brain-reactive B-cell activity by ELISPOT provides clinically meaningful predictive probabilities of individual patients' treatment response to GA or IFN-β. The assay has the potential to improve the selection of optimal first-line treatment for individual patients with RRMS.

Classification Of Evidence: This study provides Class II evidence that in patients with RRMS, the brain reactivity of their peripheral-blood B cells predicts clinical response to GA and IFN-β.
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http://dx.doi.org/10.1212/NXI.0000000000000980DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7958588PMC
May 2021

Disorders of the enteric nervous system - a holistic view.

Nat Rev Gastroenterol Hepatol 2021 Jan 29. Epub 2021 Jan 29.

Working group Enteric Nervous Systems (AGENS), University of Applied Sciences Kaiserslautern, Kaiserslautern, Germany.

The enteric nervous system (ENS) is the largest division of the peripheral nervous system and closely resembles components and functions of the central nervous system. Although the central role of the ENS in congenital enteric neuropathic disorders, including Hirschsprung disease and inflammatory and functional bowel diseases, is well acknowledged, its role in systemic diseases is less understood. Evidence of a disordered ENS has accumulated in neurodegenerative diseases ranging from amyotrophic lateral sclerosis, Alzheimer disease and multiple sclerosis to Parkinson disease as well as neurodevelopmental disorders such as autism. The ENS is a key modulator of gut barrier function and a regulator of enteric homeostasis. A 'leaky gut' represents the gateway for bacterial and toxin translocation that might initiate downstream processes. Data indicate that changes in the gut microbiome acting in concert with the individual genetic background can modify the ENS, central nervous system and the immune system, impair barrier function, and contribute to various disorders such as irritable bowel syndrome, inflammatory bowel disease or neurodegeneration. Here, we summarize the current knowledge on the role of the ENS in gastrointestinal and systemic diseases, highlighting its interaction with various key players involved in shaping the phenotypes. Finally, current flaws and pitfalls related to ENS research in addition to future perspectives are also addressed.
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http://dx.doi.org/10.1038/s41575-020-00385-2DOI Listing
January 2021

Bone marrow-derived myeloid progenitors in the leptomeninges of adult mice.

Stem Cells 2021 Feb 11;39(2):227-239. Epub 2020 Dec 11.

Institute of Anatomy and Cell Biology, Julius Maximilian University of Würzburg, Würzburg, Germany.

Although the bone marrow contains most hematopoietic activity during adulthood, hematopoietic stem and progenitor cells can be recovered from various extramedullary sites. Cells with hematopoietic progenitor properties have even been reported in the adult brain under steady-state conditions, but their nature and localization remain insufficiently defined. Here, we describe a heterogeneous population of myeloid progenitors in the leptomeninges of adult C57BL/6 mice. This cell pool included common myeloid, granulocyte/macrophage, and megakaryocyte/erythrocyte progenitors. Accordingly, it gave rise to all major myelo-erythroid lineages in clonogenic culture assays. Brain-associated progenitors persisted after tissue perfusion and were partially inaccessible to intravenous antibodies, suggesting their localization behind continuous blood vessel endothelium such as the blood-arachnoid barrier. Flt3 lineage tracing and bone marrow transplantation showed that the precursors were derived from adult hematopoietic stem cells and were most likely continuously replaced via cell trafficking. Importantly, their occurrence was tied to the immunologic state of the central nervous system (CNS) and was diminished in the context of neuroinflammation and ischemic stroke. Our findings confirm the presence of myeloid progenitors at the meningeal border of the brain and lay the foundation to unravel their possible functions in CNS surveillance and local immune cell production.
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http://dx.doi.org/10.1002/stem.3311DOI Listing
February 2021

B Cells in Multiple Sclerosis and Virus-Induced Neuroinflammation.

Front Neurol 2020 3;11:591894. Epub 2020 Nov 3.

Institute of Anatomy and Cell Biology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.

Neuroinflammation can be defined as an inflammatory response within the central nervous system (CNS) mediated by a complex crosstalk between CNS-resident and infiltrating immune cells from the periphery. Triggers for neuroinflammation not only include pathogens, trauma and toxic metabolites, but also autoimmune diseases such as neuromyelitis optica spectrum disorders and multiple sclerosis (MS) where the inflammatory response is recognized as a disease-escalating factor. B cells are not considered as the first responders of neuroinflammation, yet they have recently gained focus as a key component involved in the disease pathogenesis of several neuroinflammatory disorders like MS. Traditionally, the prime focus of the role of B cells in any disease, including neuroinflammatory diseases, was their ability to produce antibodies. While that may indeed be an important contribution of B cells in mediating disease pathogenesis, several lines of recent evidence indicate that B cells are multifunctional players during an inflammatory response, including their ability to present antigens and produce an array of cytokines. Moreover, interaction between B cells and other cellular components of the immune system or nervous system can either promote or dampen neuroinflammation depending on the disease. Given that the interest in B cells in neuroinflammation is relatively new, the precise roles that they play in the pathophysiology and progression of different neuroinflammatory disorders have not yet been well-elucidated. Furthermore, the possibility that they might change their function during the course of neuroinflammation adds another level of complexity and the puzzle remains incomplete. Indeed, advancing our knowledge on the role of B cells in neuroinflammation would also allow us to tackle these disorders better. Here, we review the available literature to explore the relationship between autoimmune and infectious neuroinflammation with a focus on the involvement of B cells in MS and viral infections of the CNS.
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http://dx.doi.org/10.3389/fneur.2020.591894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7670072PMC
November 2020

Obinutuzumab-Induced B Cell Depletion Reduces Spinal Cord Pathology in a CD20 Double Transgenic Mouse Model of Multiple Sclerosis.

Int J Mol Sci 2020 Sep 18;21(18). Epub 2020 Sep 18.

Institute of Anatomy and Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.

B cell-depleting therapies have recently proven to be clinically highly successful in the treatment of multiple sclerosis (MS). This study aimed to determine the effects of the novel type II anti-human CD20 (huCD20) monoclonal antibody (mAb) obinutuzumab (OBZ) on spinal cord degeneration in a B cell-dependent mouse model of MS. Double transgenic huCD20xHIGR3 (CD20dbtg) mice, which express human CD20, were immunised with the myelin fusion protein MP4 to induce experimental autoimmune encephalomyelitis (EAE). Both light and electron microscopy were used to assess myelination and axonal pathology in mice treated with OBZ during chronic EAE. Furthermore, the effects of the already established murine anti-CD20 antibody 18B12 were assessed in C57BL/6 wild-type (wt) mice. In both models (18B12/wt and OBZ/CD20dbtg) anti-CD20 treatment significantly diminished the extent of spinal cord pathology. While 18B12 treatment mainly reduced the extent of axonal pathology, a significant decrease in demyelination and increase in remyelination were additionally observed in OBZ-treated mice. Hence, the data suggest that OBZ could have neuroprotective effects on the CNS, setting the drug apart from the currently available type I anti-CD20 antibodies.
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http://dx.doi.org/10.3390/ijms21186864DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7559311PMC
September 2020

Autoantibodies against central nervous system antigens in a subset of B cell-dominant multiple sclerosis patients.

Proc Natl Acad Sci U S A 2020 09 18;117(35):21512-21518. Epub 2020 Aug 18.

Department of Neurology and Neurological Sciences, Beckman Center for Molecular Medicine, Stanford University, Stanford, CA 94305

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS), with characteristic inflammatory lesions and demyelination. The clinical benefit of cell-depleting therapies targeting CD20 has emphasized the role of B cells and autoantibodies in MS pathogenesis. We previously introduced an enzyme-linked immunospot spot (ELISpot)-based assay to measure CNS antigen-specific B cells in the blood of MS patients and demonstrated its usefulness as a predictive biomarker for disease activity in measuring the successful outcome of disease-modifying therapies (DMTs). Here we used a planar protein array to investigate CNS-reactive antibodies in the serum of MS patients as well as in B cell culture supernatants after polyclonal stimulation. Anti-CNS antibody reactivity was evident in the sera of the MS cohort, and the antibodies bound a heterogeneous set of molecules, including myelin, axonal cytoskeleton, and ion channel antigens, in individual patients. Immunoglobulin reactivity in supernatants of stimulated B cells was directed against a broad range of CNS antigens. A group of MS patients with a highly active B cell component was identified by the ELISpot assay. Those antibody reactivities remained stable over time. These assays with protein arrays identify MS patients with a highly active B cell population with antibodies directed against a swathe of CNS proteins.
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http://dx.doi.org/10.1073/pnas.2011249117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7474673PMC
September 2020

Strategies for Neuroprotection in Multiple Sclerosis and the Role of Calcium.

Int J Mol Sci 2020 Feb 28;21(5). Epub 2020 Feb 28.

Institute of Anatomy and Cell Biology, Friedrich-Alexander University Erlangen-Nürnberg, Krankenhausstraße 9, D-91054 Erlangen, Germany.

Calcium ions are vital for maintaining the physiological and biochemical processes inside cells. The central nervous system (CNS) is particularly dependent on calcium homeostasis and its dysregulation has been associated with several neurodegenerative disorders including Parkinson's disease (PD), Alzheimer's disease (AD) and Huntington's disease (HD), as well as with multiple sclerosis (MS). Hence, the modulation of calcium influx into the cells and the targeting of calcium-mediated signaling pathways may present a promising therapeutic approach for these diseases. This review provides an overview on calcium channels in neurons and glial cells. Special emphasis is put on MS, a chronic autoimmune disease of the CNS. While the initial relapsing-remitting stage of MS can be treated effectively with immune modulatory and immunosuppressive drugs, the subsequent progressive stage has remained largely untreatable. Here we summarize several approaches that have been and are currently being tested for their neuroprotective capacities in MS and we discuss which role calcium could play in this regard.
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http://dx.doi.org/10.3390/ijms21051663DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7084497PMC
February 2020

Same same but different: A Web-based deep learning application revealed classifying features for the histopathologic distinction of cortical malformations.

Epilepsia 2020 03 20;61(3):421-432. Epub 2020 Feb 20.

Institute of Neuropathology, University Hospitals, Erlangen, Germany.

Objective: The microscopic review of hematoxylin-eosin-stained images of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex remains challenging. Both entities are distinct subtypes of human malformations of cortical development that share histopathological features consisting of neuronal dyslamination with dysmorphic neurons and balloon cells. We trained a convolutional neural network (CNN) to classify both entities and visualize the results. Additionally, we propose a new Web-based deep learning application as proof of concept of how deep learning could enter the pathologic routine.

Methods: A digital processing pipeline was developed for a series of 56 cases of focal cortical dysplasia type IIb and cortical tuber of tuberous sclerosis complex to obtain 4000 regions of interest and 200 000 subsamples with different zoom and rotation angles to train a neural network. Guided gradient-weighted class activation maps (Guided Grad-CAMs) were generated to visualize morphological features used by the CNN to distinguish both entities.

Results: Our best-performing network achieved 91% accuracy and 0.88 area under the receiver operating characteristic curve at the tile level for an unseen test set. Novel histopathologic patterns were found through the visualized Guided Grad-CAMs. These patterns were assembled into a classification score to augment decision-making in routine histopathology workup. This score was successfully validated by 11 expert neuropathologists and 12 nonexperts, boosting nonexperts to expert level performance.

Significance: Our newly developed Web application combines the visualization of whole slide images with the possibility of deep learning-aided classification between focal cortical dysplasia IIb and tuberous sclerosis complex. This approach will help to introduce deep learning applications and visualization for the histopathologic diagnosis of rare and difficult-to-classify brain lesions.
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http://dx.doi.org/10.1111/epi.16447DOI Listing
March 2020

IL-21 in Conjunction with Anti-CD40 and IL-4 Constitutes a Potent Polyclonal B Cell Stimulator for Monitoring Antigen-Specific Memory B Cells.

Cells 2020 02 13;9(2). Epub 2020 Feb 13.

Research & Development Department, Cellular Technology Limited, Shaker Heights, OH 44122, USA.

Detection of antigen-specific memory B cells for immune monitoring requires their activation, and is commonly accomplished through stimulation with the TLR7/8 agonist R848 and IL-2. To this end, we evaluated whether addition of IL-21 would further enhance this TLR-driven stimulation approach; which it did not. More importantly, as most antigen-specific B cell responses are T cell-driven, we sought to devise a polyclonal B cell stimulation protocol that closely mimics T cell help. Herein, we report that the combination of agonistic anti-CD40, IL-4 and IL-21 affords polyclonal B cell stimulation that was comparable to R848 and IL-2 for detection of influenza-specific memory B cells. An additional advantage of anti-CD40, IL-4 and IL-21 stimulation is the selective activation of IgM memory B cells, as well as the elicitation of IgE ASC, which the former fails to do. Thereby, we introduce a protocol that mimics physiological B cell activation through helper T cells, including induction of all Ig classes, for immune monitoring of antigen-specific B cell memory.
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http://dx.doi.org/10.3390/cells9020433DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7072853PMC
February 2020

Nav1.6 promotes inflammation and neuronal degeneration in a mouse model of multiple sclerosis.

J Neuroinflammation 2019 Nov 13;16(1):215. Epub 2019 Nov 13.

Department of Biology, Dalhousie University, Halifax, NS, B3H 4R2, Canada.

Background: In multiple sclerosis (MS) and in the experimental autoimmune encephalomyelitis (EAE) model of MS, the Nav1.6 voltage-gated sodium (Nav) channel isoform has been implicated as a primary contributor to axonal degeneration. Following demyelination Nav1.6, which is normally co-localized with the Na/Ca exchanger (NCX) at the nodes of Ranvier, associates with β-APP, a marker of neural injury. The persistent influx of sodium through Nav1.6 is believed to reverse the function of NCX, resulting in an increased influx of damaging Ca ions. However, direct evidence for the role of Nav1.6 in axonal degeneration is lacking.

Methods: In mice floxed for Scn8a, the gene that encodes the α subunit of Nav1.6, subjected to EAE we examined the effect of eliminating Nav1.6 from retinal ganglion cells (RGC) in one eye using an AAV vector harboring Cre and GFP, while using the contralateral either injected with AAV vector harboring GFP alone or non-targeted eye as control.

Results: In retinas, the expression of Rbpms, a marker for retinal ganglion cells, was found to be inversely correlated to the expression of Scn8a. Furthermore, the gene expression of the pro-inflammatory cytokines Il6 (IL-6) and Ifng (IFN-γ), and of the reactive gliosis marker Gfap (GFAP) were found to be reduced in targeted retinas. Optic nerves from targeted eyes were shown to have reduced macrophage infiltration and improved axonal health.

Conclusion: Taken together, our results are consistent with Nav1.6 promoting inflammation and contributing to axonal degeneration following demyelination.
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http://dx.doi.org/10.1186/s12974-019-1622-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6852902PMC
November 2019

Aged hind-limb clasping experimental autoimmune encephalomyelitis models aspects of the neurodegenerative process seen in multiple sclerosis.

Proc Natl Acad Sci U S A 2019 11 22;116(45):22710-22720. Epub 2019 Oct 22.

Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada;

Experimental autoimmune encephalomyelitis (EAE) is the most common model of multiple sclerosis (MS). This model has been instrumental in understanding the events that lead to the initiation of central nervous system (CNS) autoimmunity. Though EAE has been an effective screening tool for identifying novel therapies for relapsing-remitting MS, it has proven to be less successful in identifying therapies for progressive forms of this disease. Though axon injury occurs in EAE, it is rapid and acute, making it difficult to intervene for the purpose of evaluating neuroprotective therapies. Here, we describe a variant of spontaneous EAE in the 2D2 T cell receptor transgenic mouse (2D2 mouse) that presents with hind-limb clasping upon tail suspension and is associated with T cell-mediated inflammation in the posterior spinal cord and spinal nerve roots. Due to the mild nature of clinical signs in this model, we were able to maintain cohorts of mice into middle age. Over 9 mo, these mice exhibited a relapsing-remitting course of hind-limb clasping with the development of progressive motor deficits. Using a combined approach of ex vivo magnetic resonance (MR) imaging and histopathological analysis, we observed neurological progression to associate with spinal cord atrophy, synapse degradation, and neuron loss in the gray matter, as well as ongoing axon injury in the white matter of the spinal cord. These findings suggest that mild EAE coupled with natural aging may be a solution to better modeling the neurodegenerative processes seen in MS.
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http://dx.doi.org/10.1073/pnas.1915141116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6842635PMC
November 2019

Contribution of LTi and T17 cells to B cell aggregate formation in the central nervous system in a mouse model of multiple sclerosis.

J Neuroinflammation 2019 May 28;16(1):111. Epub 2019 May 28.

Institute of Anatomy, Chair of Anatomy and Cell Biology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.

Background: In a subgroup of patients suffering from progressive multiple sclerosis (MS), which is an inflammation-mediated neurodegenerative disease of the central nervous system (CNS), B cell aggregates were discovered within the meninges. Occurrence of these structures was associated with a more severe disease course and cortical histopathology. We have developed the B cell-dependent MP4-induced experimental autoimmune encephalomyelitis (EAE) as a mouse model to mimic this trait of the human disease. The aim of this study was to determine a potential role of lymphoid tissue inducer (LTi) and T17 cells in the process of B cell aggregate formation in the MP4 model.

Methods: We performed flow cytometry of cerebellar and splenic tissue of MP4-immunized mice in the acute and chronic stage of the disease to analyze the presence of CD3CD5CD4RORγt LTi and CD3CD5CD4RORγt T17 cells. Myelin oligodendrocyte glycoprotein (MOG):35-55-induced EAE was used as B cell-independent control model. We further determined the gene expression profile of B cell aggregates using laser capture microdissection, followed by RNA sequencing.

Results: While we were able to detect LTi cells in the embryonic spleen and adult intestine, which served as positive controls, there was no evidence for the existence of such a population in acute or chronic EAE in neither of the two models. Yet, we detected CD3CD5CD4RORγt innate lymphoid cells (ILCs) and T17 cells in the CNS, the latter especially in the chronic stage of MP4-induced EAE. Moreover, we observed a unique gene signature in CNS B cell aggregates compared to draining lymph nodes of MP4-immunized mice and to cerebellum as well as draining lymph nodes of mice with MOG:35-55-induced EAE.

Conclusion: The absence of LTi cells in the cerebellum suggests that other cells might take over the function as an initiator of lymphoid tissue formation in the CNS. Overall, the development of ectopic lymphoid organs is a complex process based on an interplay between several molecules and signals. Here, we propose some potential candidates, which might be involved in the formation of B cell aggregates in the CNS of MP4-immunized mice.
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http://dx.doi.org/10.1186/s12974-019-1500-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6540524PMC
May 2019

Severe bornavirus-encephalitis presenting as Guillain-Barré-syndrome.

Acta Neuropathol 2019 06 5;137(6):1017-1019. Epub 2019 Apr 5.

Institute of Virology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Schlossgarten 4, 91054, Erlangen, Germany.

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http://dx.doi.org/10.1007/s00401-019-02005-zDOI Listing
June 2019

Characterization of blood-brain barrier integrity in a B-cell-dependent mouse model of multiple sclerosis.

Histochem Cell Biol 2019 Jun 21;151(6):489-499. Epub 2019 Jan 21.

Department of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.

Recent studies with B-cell-depleting antibodies have demonstrated clinical success in the treatment of multiple sclerosis (MS) patients. While these antibodies efficiently target B cells in the blood, it is unclear how effective they are in the central nervous system (CNS), especially in the context of limited blood-brain barrier (BBB) permeability and the ongoing discussion on the relevance of B-cell aggregate formation in the brains of SP-MS patients. The aim of this study was to evaluate BBB integrity in the context of B-cell-dependent neuroinflammation in a mouse model of MS. C57BL/6 mice were actively immunized with either myelin oligodendrocyte glycoprotein peptide 35-55 to induce T-cell-dependent experimental autoimmune encephalomyelitis (EAE), or with the myelin basic protein-proteolipid protein fusion protein MP4 for additional B-cell dependence. BBB integrity was assessed using Evans Blue or fluorescein isothiocyanate-dextran injection, respectively, in combination with immunofluorescence staining for key components of the BBB. In both EAE models, tracer leakage into the CNS parenchyma was observed indicating BBB leakiness. Yet, intensity and distribution patterns of leakage differed between the two models. There was no difference in the severity of BBB damage comparing acute and chronic MP4-induced EAE, but the formation of B-cell aggregates was associated with local BBB impairment in this model. This study underscores that a leaky BBB is a characteristic feature of EAE, but it also suggests that extent and region specificity of BBB damage differs between individual EAE models that vary in the underlying immunopathology.
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http://dx.doi.org/10.1007/s00418-019-01768-6DOI Listing
June 2019

Generation of Cardiomyocytes From Vascular Adventitia-Resident Stem Cells.

Circ Res 2018 08;123(6):686-699

From the Institute of Anatomy and Cell Biology II (S.R.M., P.W., J.B., O.S., N.W., L.R., K.L., G.E., C.K.K., F.E., V.P., S.K., S.E.).

Rationale: Regeneration of lost cardiomyocytes is a fundamental unresolved problem leading to heart failure. Despite several strategies developed from intensive studies performed in the past decades, endogenous regeneration of heart tissue is still limited and presents a big challenge that needs to be overcome to serve as a successful therapeutic option for myocardial infarction.

Objective: One of the essential prerequisites for cardiac regeneration is the identification of endogenous cardiomyocyte progenitors and their niche that can be targeted by new therapeutic approaches. In this context, we hypothesized that the vascular wall, which was shown to harbor different types of stem and progenitor cells, might serve as a source for cardiac progenitors.

Methods And Results: We describe generation of spontaneously beating mouse aortic wall-derived cardiomyocytes without any genetic manipulation. Using aortic wall-derived cells (AoCs) of WT (wild type), αMHC (α-myosin heavy chain), and Flk1 (fetal liver kinase 1)-reporter mice and magnetic bead-associated cell sorting sorting of Flk1 AoCs from GFP (green fluorescent protein) mice, we identified Flk1CD (cluster of differentiation) 34Sca-1 (stem cell antigen-1)-CD44 AoCs as the population that gives rise to aortic wall-derived cardiomyocytes. This AoC subpopulation delivered also endothelial cells and macrophages with a particular accumulation within the aortic wall-derived cardiomyocyte containing colonies. In vivo, cardiomyocyte differentiation capacity was studied by implantation of fluorescently labeled AoCs into chick embryonic heart. These cells acquired cardiomyocyte-like phenotype as shown by αSRA (α-sarcomeric actinin) expression. Furthermore, coronary adventitial Flk1 and CD34 cells proliferated, migrated into the myocardium after mouse myocardial infarction, and expressed Isl-1 (insulin gene enhancer protein-1) indicative of cardiovascular progenitor potential.

Conclusions: Our data suggest Flk1CD34 vascular adventitia-resident stem cells, including those of coronary adventitia, as a novel endogenous source for generating cardiomyocytes. This process is essentially supported by endothelial cells and macrophages. In summary, the therapeutic manipulation of coronary adventitia-resident cardiac stem and their supportive cells may open new avenues for promoting cardiac regeneration and repair after myocardial infarction and for preventing heart failure.
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http://dx.doi.org/10.1161/CIRCRESAHA.117.312526DOI Listing
August 2018

Impact of Glatiramer Acetate on B Cell-Mediated Pathogenesis of Multiple Sclerosis.

CNS Drugs 2018 11;32(11):1039-1051

Department of Neurology, University of Colorado at Denver, Aurora, CO, USA.

Growing evidence indicates that B cells play a key role in the pathogenesis of multiple sclerosis (MS). B cells occupy distinct central nervous system (CNS) compartments in MS, including the cerebrospinal fluid and white matter lesions. Also, it is now known that, in addition to entering the CNS, B cells can circulate into the periphery via a functional lymphatic system. Data suggest that the role of B cells in MS mainly involves their in situ activation in demyelinating lesions, leading to altered pro- and anti-inflammatory cytokine secretion, and a highly effective antigen-presenting cell function, resulting in activation of memory or naïve T cells. Clinically, B cell-depleting agents show significant efficacy in MS. In addition, many disease-modifying therapies (DMTs) traditionally understood to target T cells are now known to influence B cell number and function. One of the earliest DMTs to be developed, glatiramer acetate (GA), has been shown to reduce the total frequency of B cells, plasmablasts, and memory B cells. It also appears to promote a shift toward reduced inflammation by increasing anti-inflammatory cytokine release and/or reducing pro-inflammatory cytokine release by B cells. In the authors' opinion, this may be mediated by cross-reactivity of B cell receptors for GA with antigen (possibly myelin basic protein) expressed in the MS lesion. More research is required to further characterize the role of B cells and their bidirectional trafficking in the pathogenesis of MS. This may uncover novel targets for MS treatments and facilitate the development of B cell biomarkers of drug response.
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http://dx.doi.org/10.1007/s40263-018-0567-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6223706PMC
November 2018

Digital pathology imaging and computer-aided diagnostics as a novel tool for standardization of evaluation of aganglionic megacolon (Hirschsprung disease) histopathology.

Cell Tissue Res 2019 Feb 3;375(2):371-381. Epub 2018 Sep 3.

Institute of Anatomy and Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstraße 9, 91054, Erlangen, Germany.

Based on a recently introduced immunohistochemical panel (Bachmann et al. 2015) for aganglionic megacolon (AM), also known as Hirschsprung disease, histopathological diagnosis, we evaluated whether the use of digital pathology and 'machine learning' could help to obtain a reliable diagnosis. Slides were obtained from 31 specimens of 27 patients immunohistochemically stained for MAP2, calretinin, S100β and GLUT1. Slides were digitized by whole slide scanning. We used a Definiens Developer Tissue Studios as software for analysis. We configured necessary parameters in combination with 'machine learning' to identify pathological aberrations. A significant difference between AM- and non-AM-affected tissues was found for calretinin (AM 0.55% vs. non-AM 1.44%) and MAP2 (AM 0.004% vs. non-AM 0.07%) staining measurements and software-based evaluations. In contrast, S100β and GLUT1 staining measurements and software-based evaluations showed no significant differences between AM- and non-AM-affected tissues. However, no difference was found in comparison of suction biopsies with resections. Applying machine learning via an ensemble voting classifier, we achieved an accuracy of 87.5% on the test set. Automated diagnosis of AM by applying digital pathology on immunohistochemical panels was successful for calretinin and MAP2, whereas S100β and GLUT1 were not effective in diagnosis. Our method suggests that software-based approaches are capable of diagnosing AM. Our future challenge will be the improvement of efficiency by reduction of the time-consuming need for large pre-labelled training data. With increasing technical improvement, especially in unsupervised training procedures, this method could be helpful in the future.
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http://dx.doi.org/10.1007/s00441-018-2911-1DOI Listing
February 2019

Anti-CD52 antibody treatment depletes B cell aggregates in the central nervous system in a mouse model of multiple sclerosis.

J Neuroinflammation 2018 Aug 11;15(1):225. Epub 2018 Aug 11.

Department of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.

Background: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) for which several new treatment options were recently introduced. Among them is the monoclonal anti-CD52 antibody alemtuzumab that depletes mainly B cells and T cells in the immune periphery. Considering the ongoing controversy about the involvement of B cells and in particular the formation of B cell aggregates in the brains of progressive MS patients, an in-depth understanding of the effects of anti-CD52 antibody treatment on the B cell compartment in the CNS itself is desirable.

Methods: We used myelin basic protein (MBP)-proteolipid protein (PLP)-induced experimental autoimmune encephalomyelitis (EAE) in C57BL/6 (B6) mice as B cell-dependent model of MS. Mice were treated intraperitoneally either at the peak of EAE or at 60 days after onset with 200 μg murine anti-CD52 vs. IgG2a isotype control antibody for five consecutive days. Disease was subsequently monitored for 10 days. The antigen-specific B cell/antibody response was measured by ELISPOT and ELISA. Effects on CNS infiltration and B cell aggregation were determined by immunohistochemistry. Neurodegeneration was evaluated by Luxol Fast Blue, SMI-32, and Olig2/APC staining as well as by electron microscopy and phosphorylated heavy neurofilament serum ELISA.

Results: Treatment with anti-CD52 antibody attenuated EAE only when administered at the peak of disease. While there was no effect on the production of MP4-specific IgG, the treatment almost completely depleted CNS infiltrates and B cell aggregates even when given as late as 60 days after onset. On the ultrastructural level, we observed significantly less axonal damage in the spinal cord and cerebellum in chronic EAE after anti-CD52 treatment.

Conclusion: Anti-CD52 treatment abrogated B cell infiltration and disrupted existing B cell aggregates in the CNS.
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http://dx.doi.org/10.1186/s12974-018-1263-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6086993PMC
August 2018

B Cells and B Cell Blasts Withstand Cryopreservation While Retaining Their Functionality for Producing Antibody.

Cells 2018 May 31;7(6). Epub 2018 May 31.

Research & Development Department, Cellular Technology Limited, Shaker Heights, OH 44122, USA.

In individuals who have once developed humoral immunity to an infectious/foreign antigen, the antibodies present in their body can mediate instant protection when the antigen re-enters. Such antigen-specific antibodies can be readily detected in the serum. Long term humoral immunity is, however, also critically dependent on the ability of memory B cells to engage in a secondary antibody response upon re-exposure to the antigen. Antibody molecules in the body are short lived, having a half-life of weeks, while memory B cells have a life span of decades. Therefore, the presence of serum antibodies is not always a reliable indicator of B cell memory and comprehensive monitoring of humoral immunity requires that both serum antibodies and memory B cells be assessed. The prevailing view is that resting memory B cells and B cell blasts in peripheral blood mononuclear cells (PBMC) cannot be cryopreserved without losing their antibody secreting function, and regulated high throughput immune monitoring of B cell immunity is therefore confined to-and largely limited by-the need to test freshly isolated PBMC. Using optimized protocols for freezing and thawing of PBMC, and four color ImmunoSpot analysis for the simultaneous detection of all immunoglobulin classes/subclasses we show here that both resting memory B cells and B cell blasts retain their ability to secrete antibody after thawing, and thus demonstrate the feasibility of B cell immune monitoring using cryopreserved PBMC.
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http://dx.doi.org/10.3390/cells7060050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6028916PMC
May 2018

Direct Detection of T- and B-Memory Lymphocytes by ImmunoSpot® Assays Reveals HCMV Exposure that Serum Antibodies Fail to Identify.

Cells 2018 May 19;7(5). Epub 2018 May 19.

Research & Development Department, Cellular Technology Limited, Shaker Heights, OH 44122, USA.

It is essential to identify donors who have not been infected with human cytomegalovirus (HCMV) in order to avoid transmission of HCMV to recipients of blood transfusions or organ transplants. In the present study, we tested the reliability of seronegativity as an indicator for the lack of HCMV exposure in healthy human blood donors. Eighty-two HCMV seronegative individuals were identified, and their peripheral blood mononuclear cells (PBMC) were tested in ImmunoSpot® assays for the presence of HCMV-specific T- and B-memory lymphocytes. Eighty-two percent (67 of 82) of these HCMV seronegative individuals featured at least one memory cell that was lineage specific for HCMV, with the majority of these subjects possessing CD4+ and CD8+ T cells, as well as B cells, providing three independent lines of evidence for having developed immunity to HCMV. Only 15 of these 82 donors (18%) showed neither T- nor B-cell memory to HCMV, consistent with immunological naïveté to the virus. The data suggest that measurements of serum antibodies frequently fail to reveal HCMV exposure in humans, which may be better identified by direct detection of HCMV-specific memory lymphocytes.
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http://dx.doi.org/10.3390/cells7050045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5981269PMC
May 2018

High-Throughput GLP-Capable Target Cell Visualization Assay for Measuring Cell-Mediated Cytotoxicity.

Cells 2018 Apr 24;7(5). Epub 2018 Apr 24.

Research & Development Department, Cellular Technology Limited, Shaker Heights, OH 44122, USA.

One of the primary effector functions of immune cells is the killing of virus-infected or malignant cells in the body. Natural killer (NK) and CD8 effector T cells are specialized for this function. The gold standard for measuring such cell-mediated cytolysis has been the chromium release assay, in which the leakage of the radioactive isotope from damaged target cells is being detected. Flow cytometry-based single cell analysis of target cells has recently been established as a non-radioactive alternative. Here we introduce a target cell visualization assay (TVA) that applies similar target cell staining approaches as used in flow cytometry but based on single cell computer image analysis. Two versions of TVA are described here. In one, the decrease in numbers of calcein-stained, i.e., viable, target cells is assessed. In the other, the CFSE/PI TVA, the increase in numbers of dead target cells is established in addition. TVA assays are shown to operate with the same sensitivity as standard chromium release assays, and, leaving data audit trails in form of scanned (raw), analyzed, and quality-controlled images, thus meeting requirements for measuring cell-mediated cytolysis in a regulated environment.
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http://dx.doi.org/10.3390/cells7050035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5981259PMC
April 2018

Calbindin D28k-Immunoreactivity in Human Enteric Neurons.

Int J Mol Sci 2018 Jan 8;19(1). Epub 2018 Jan 8.

Institute of Anatomy and Cell Biology, University of Erlangen-Nuremberg, Krankenhausstraße 9, D-91054 Erlangen, Germany.

Calbindin (CALB) is well established as immunohistochemical marker for intrinsic primary afferent neurons in the guinea pig gut. Its expression by numerous human enteric neurons has been demonstrated but little is known about particular types of neurons immunoreactive for CALB. Here we investigated small and large intestinal wholemount sets of 26 tumor patients in order to evaluate (1) the proportion of CALB⁺ neurons in the total neuron population, (2) the colocalization of CALB with calretinin (CALR), somatostatin (SOM) and vasoactive intestinal peptide (VIP) and (3) the morphology of CALB neurons. CALB neurons represented a minority of myenteric neurons (small intestine: 31%; large intestine: 25%) and the majority of submucosal neurons (between 72 and 95%). In the submucosa, most CALB⁺ neurons co-stained for CALR and VIP (between 69 and 80%) or for SOM (between 20 and 3%). In the myenteric plexus, 85% of CALB neurons did not co-stain with the other markers investigated. An unequivocal correlation between CALB reactivity and neuronal morphology was found for myenteric type III neurons in the small intestine: uniaxonal neurons with long, slender and branched dendrites were generally positive for CALB. Since also other neurons displayed occasional CALB reactivity, this protein is not suited as an exclusive marker for type III neurons.
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http://dx.doi.org/10.3390/ijms19010194DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5796143PMC
January 2018

A Positive Control for Detection of Functional CD4 T Cells in PBMC: The CPI Pool.

Cells 2017 Dec 7;6(4). Epub 2017 Dec 7.

Research&Development Department, Cellular Technology Limited, Shaker Heights, OH 44122, USA.

Testing of peripheral blood mononuclear cells (PBMC) for immune monitoring purposes requires verification of their functionality. This is of particular concern when the PBMC have been shipped or stored for prolonged periods of time. While the CEF (Cytomegalo-, Epstein-Barr and Flu-virus) peptide pool has become the gold standard for testing CD8 cell functionality, a positive control for CD4 cells is so far lacking. The latter ideally consists of proteins so as to control for the functionality of the antigen processing and presentation compartments, as well. Aiming to generate a positive control for CD4 cells, we first selected 12 protein antigens from infectious/environmental organisms that are ubiquitous: Varicella, Influenza, Parainfluenza, Mumps, Cytomegalovirus, , , , , , Rubella, and Measles. Of these antigens, three were found to elicited interferon (IFN)-γ-producing CD4 cells in the majority of human test subjects: inactivated cytomegalo-, parainfluenza-, and influenza virions (CPI). While individually none of these three antigens triggered a recall response in all donors, the pool of the three (the 'CPI pool'), did. One hundred percent of 245 human donors tested were found to be CPI positive, including Caucasians, Asians, and African-Americans. Therefore, the CPI pool appears to be suitable to serve as universal positive control for verifying the functionality of CD4 and of antigen presenting cells.
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http://dx.doi.org/10.3390/cells6040047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5753071PMC
December 2017

Danger: High Voltage-The Role of Voltage-Gated Calcium Channels in Central Nervous System Pathology.

Cells 2017 Nov 15;6(4). Epub 2017 Nov 15.

Institute of Anatomy and Cell Biology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen 91054, Germany.

Voltage-gated calcium channels (VGCCs) are widely distributed within the central nervous system (CNS) and presumed to play an important role in the pathophysiology of a broad spectrum of CNS disorders including Alzheimer's and Parkinson's disease as well as multiple sclerosis. Several calcium channel blockers have been in clinical practice for many years so that their toxicity and side effects are well studied. However, these drugs are primarily used for the treatment of cardiovascular diseases and most if not all effects on brain functions are secondary to peripheral effects on blood pressure and circulation. While the use of calcium channel antagonists for the treatment of CNS diseases therefore still heavily depends on the development of novel strategies to specifically target different channels and channel subunits, this review is meant to provide an impulse to further emphasize the importance of future research towards this goal.
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http://dx.doi.org/10.3390/cells6040043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5755501PMC
November 2017

Splitting the "Unsplittable": Dissecting Resident and Infiltrating Macrophages in Experimental Autoimmune Encephalomyelitis.

Int J Mol Sci 2017 Sep 29;18(10). Epub 2017 Sep 29.

Institute of Anatomy and Cell Biology, University of Würzburg, D-97070 Würzburg, Germany.

Macrophages predominate the inflammatory landscape within multiple sclerosis (MS) lesions, not only regarding cellularity but also with respect to the diverse functions this cell fraction provides during disease progression and remission. Researchers have been well aware of the fact that the macrophage pool during central nervous system (CNS) autoimmunity consists of a mixture of myeloid cells. Yet, separating these populations to define their unique contribution to disease pathology has long been challenging due to their similar marker expression. Sophisticated lineage tracing approaches as well as comprehensive transcriptome analysis have elevated our insight into macrophage biology to a new level enabling scientists to dissect the roles of resident (microglia and non-parenchymal macrophages) and infiltrating macrophages with unprecedented precision. To do so in an accurate way, researchers have to know their toolbox, which has been filled with diverse, discriminating approaches from decades of studying neuroinflammation in animal models. Every method has its own strengths and weaknesses, which will be addressed in this review. The focus will be on tools to manipulate and/or identify different macrophage subgroups within the injured murine CNS.
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http://dx.doi.org/10.3390/ijms18102072DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5666754PMC
September 2017

Delayed Activation Kinetics of Th2- and Th17 Cells Compared to Th1 Cells.

Cells 2017 Sep 12;6(3). Epub 2017 Sep 12.

R & D Department CTL, Shaker Hts, OH 44122, USA.

During immune responses, different classes of T cells arise: Th1, Th2, and Th17. Mobilizing the right class plays a critical role in successful host defense and therefore defining the ratios of Th1/Th2/Th17 cells within the antigen-specific T cell repertoire is critical for immune monitoring purposes. Antigen-specific Th1, Th2, and Th17 cells can be detected by challenging peripheral blood mononuclear cells (PBMC) with antigen, and establishing the numbers of T cells producing the respective lead cytokine, IFN-γ and IL-2 for Th1 cells, IL-4 and IL-5 for Th2, and IL-17 for Th-17 cells, respectively. Traditionally, these cytokines are measured within 6 h in flow cytometry. We show here that 6 h of stimulation is sufficient to detect peptide-induced production of IFN-γ, but 24 h are required to reveal the full frequency of protein antigen-specific Th1 cells. Also the detection of IL-2 producing Th1 cells requires 24 h stimulation cultures. Measurements of IL-4 producing Th2 cells requires 48-h cultures and 96 h are required for frequency measurements of IL-5 and IL-17 secreting T cells. Therefore, accounting for the differential secretion kinetics of these cytokines is critical for the accurate determination of the frequencies and ratios of antigen-specific Th1, Th2, and Th17 cells.
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http://dx.doi.org/10.3390/cells6030029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5617975PMC
September 2017

Differential effects of FTY720 on the B cell compartment in a mouse model of multiple sclerosis.

J Neuroinflammation 2017 07 24;14(1):148. Epub 2017 Jul 24.

Department of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.

Background: MP4-induced experimental autoimmune encephalomyelitis (EAE) is a mouse model of multiple sclerosis (MS), which enables targeted research on B cells, currently much discussed protagonists in MS pathogenesis. Here, we used this model to study the impact of the S1P receptor modulator FTY720 (fingolimod) on the autoreactive B cell and antibody response both in the periphery and the central nervous system (CNS).

Methods: MP4-immunized mice were treated orally with FTY720 for 30 days at the peak of disease or 50 days after EAE onset. The subsequent disease course was monitored and the MP4-specific B cell/antibody response was measured by ELISPOT and ELISA. RNA sequencing was performed to determine any effects on B cell-relevant gene expression. S1P receptor expression by peripheral T and B cells, B cell subset distribution in the spleen and B cell infiltration into the CNS were studied by flow cytometry. The formation of B cell aggregates and of tertiary lymphoid organs (TLOs) was evaluated by histology and immunohistochemistry. Potential direct effects of FTY720 on B cell aggregation were studied in vitro.

Results: FTY720 significantly attenuated clinical EAE when treatment was initiated at the peak of EAE. While there was a significant reduction in the number of T cells in the blood after FTY720 treatment, B cells were only slightly diminished. Yet, there was evidence for the modulation of B cell receptor-mediated signaling upon FTY720 treatment. In addition, we detected a significant increase in the percentage of B220 B cells in the spleen both in acute and chronic EAE. Whereas acute treatment completely abrogated B cell aggregate formation in the CNS, the numbers of infiltrating B cells and plasma cells were comparable between vehicle- and FTY720-treated mice. In addition, there was no effect on already developed aggregates in chronic EAE. In vitro B cell aggregation assays suggested the absence of a direct effect of FTY720 on B cell aggregation. However, FTY720 impacted the evolution of B cell aggregates into TLOs.

Conclusions: The data suggest differential effects of FTY720 on the B cell compartment in MP4-induced EAE.
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http://dx.doi.org/10.1186/s12974-017-0924-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5525315PMC
July 2017

The enteric nervous system is a potential autoimmune target in multiple sclerosis.

Acta Neuropathol 2017 08 15;134(2):281-295. Epub 2017 Jun 15.

Department of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) in young adults that has serious negative socioeconomic effects. In addition to symptoms caused by CNS pathology, the majority of MS patients frequently exhibit gastrointestinal dysfunction, which was previously either explained by the presence of spinal cord lesions or not directly linked to the autoimmune etiology of the disease. Here, we studied the enteric nervous system (ENS) in a B cell- and antibody-dependent mouse model of MS by immunohistochemistry and electron microscopy at different stages of the disease. ENS degeneration was evident prior to the development of CNS lesions and the onset of neurological deficits in mice. The pathology was antibody mediated and caused a significant decrease in gastrointestinal motility, which was associated with ENS gliosis and neuronal loss. We identified autoantibodies against four potential target antigens derived from enteric glia and/or neurons by immunoprecipitation and mass spectrometry. Antibodies against three of the target antigens were also present in the plasma of MS patients as confirmed by ELISA. The analysis of human colon resectates provided evidence of gliosis and ENS degeneration in MS patients compared to non-MS controls. For the first time, this study establishes a pathomechanistic link between the well-established autoimmune attack on the CNS and ENS pathology in MS, which might provide a paradigm shift in our current understanding of the immunopathogenesis of the disease with broad diagnostic and therapeutic implications.
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http://dx.doi.org/10.1007/s00401-017-1742-6DOI Listing
August 2017