@article{SimonIpekHomolaetal.2018, author = {Simon, Micha and Ipek, Rojda and Homola, Gy{\"o}rgy A. and Rovituso, Damiano M. and Schampel, Andrea and Kleinschnitz, Christoph and Kuerten, Stefanie}, title = {Anti-CD52 antibody treatment depletes B cell aggregates in the central nervous system in a mouse model of multiple sclerosis}, series = {Journal of Neuroinflammation}, volume = {15}, journal = {Journal of Neuroinflammation}, number = {225}, doi = {10.1186/s12974-018-1263-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176120}, year = {2018}, abstract = {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.}, language = {en} } @article{GernertTonySchwanecketal.2019, author = {Gernert, Michael and Tony, Hans-Peter and Schwaneck, Eva Christina and Gadeholt, Ottar and Schmalzing, Marc}, title = {Autologous hematopoietic stem cell transplantation in systemic sclerosis induces long-lasting changes in B cell homeostasis toward an anti-inflammatory B cell cytokine pattern}, series = {Arthritis Research \& Therapy}, volume = {21}, journal = {Arthritis Research \& Therapy}, doi = {10.1186/s13075-019-1889-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201004}, pages = {106}, year = {2019}, abstract = {Background Autologous hematopoietic stem cell transplantation (aHSCT) is performed in patients with aggressive forms of systemic sclerosis (SSc). The profile of B cell reconstitution after aHSCT is not fully understood. The aim of this study was to investigate changes of B cell subsets and cytokine production of B cells in patients with SSc after aHSCT. Methods Peripheral blood of six patients with SSc was collected at defined intervals up to 16 months after aHSCT. Immunophenotyping was performed, and B cell function was determined by measuring cytokine secretion in supernatants of stimulated B cell cultures. Results Within 1 month after aHSCT, a peak in the percentage of CD38\(^{++}\)/CD10\(^+\)/IgD\(^+\) transitional B cells and CD38\(^{++}\)/CD27\(^{++}\)/IgD\(^-\) plasmablasts was detected. Long-term changes persisted up to 14 months after aHSCT and showed an increased percentage of total B cells; the absolute B cell number did not change significantly. Within the B cell compartment, an increased CD27/IgD\(^+\) na{\"i}ve B cell percentage was found whereas decreased percentages of CD27\(^+\)/IgD\(^+\) pre-switched memory, CD27\(^+\)/IgD\(^-\) post-switched memory, and CD27\(^-\) /IgD\(^-\) double-negative B cells were seen after aHSCT. Cytokine secretion in B cell cultures showed significantly increased IL-10 concentrations 13 to 16 months after aHSCT. Conclusion A changed composition of the B cell compartment is present for up to 14 months after aHSCT indicating positive persisting effects of aHSCT on B cell homeostasis. The cytokine secretion profile of B cells changes in the long term and shows an increased production of the immune regulatory cytokine IL-10 after aHSCT. These findings might promote the clinical improvements after aHSCT in SSc patients.}, language = {en} } @article{TraubHusseiniWeber2021, author = {Traub, Jan and Husseini, Leila and Weber, Martin S.}, title = {B cells and antibodies as targets of therapeutic intervention in neuromyelitis optica spectrum disorders}, series = {Pharmaceuticals}, volume = {14}, journal = {Pharmaceuticals}, number = {1}, issn = {1424-8247}, doi = {10.3390/ph14010037}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-222957}, year = {2021}, abstract = {The first description of neuromyelitis optica by Eug{\`e}ne Devic and Fernand Gault dates back to the 19th century, but only the discovery of aquaporin-4 autoantibodies in a major subset of affected patients in 2004 led to a fundamentally revised disease concept: Neuromyelits optica spectrum disorders (NMOSD) are now considered autoantibody-mediated autoimmune diseases, bringing the pivotal pathogenetic role of B cells and plasma cells into focus. Not long ago, there was no approved medication for this deleterious disease and off-label therapies were the only treatment options for affected patients. Within the last years, there has been a tremendous development of novel therapies with diverse treatment strategies: immunosuppression, B cell depletion, complement factor antagonism and interleukin-6 receptor blockage were shown to be effective and promising therapeutic interventions. This has led to the long-expected official approval of eculizumab in 2019 and inebilizumab in 2020. In this article, we review current pathogenetic concepts in NMOSD with a focus on the role of B cells and autoantibodies as major contributors to the propagation of these diseases. Lastly, by highlighting promising experimental and future treatment options, we aim to round up the current state of knowledge on the therapeutic arsenal in NMOSD.}, language = {en} } @article{SchuhmannLanghauserKraftetal.2017, author = {Schuhmann, Michael K. and Langhauser, Friederike and Kraft, Peter and Kleinschnitz, Christoph}, title = {B cells do not have a major pathophysiologic role in acute ischemic stroke in mice}, series = {Journal of Neuroinflammation}, volume = {14}, journal = {Journal of Neuroinflammation}, number = {112}, doi = {10.1186/s12974-017-0890-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158155}, year = {2017}, abstract = {Background Lymphocytes have been shown to play an important role in the pathophysiology of acute ischemic stroke, but the properties of B cells remain controversial. The aim of this study was to unravel the role of B cells during acute cerebral ischemia using pharmacologic B cell depletion, B cell transgenic mice, and adoptive B cell transfer experiments. Methods Transient middle cerebral artery occlusion (60 min) was induced in wild-type mice treated with an anti-CD20 antibody 24 h before stroke onset, JHD\(^{-/-}\) mice and Rag1\(^{-/-}\) mice 24 h after adoptive B cell transfer. Stroke outcome was assessed at days 1 and 3. Infarct volumes were calculated from 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain sections, and neurological scores were evaluated. The local inflammatory response was determined by real-time PCR and immunohistochemistry. Apoptosis was analyzed by TUNEL staining, and astrocyte activation was revealed using immunohistochemistry and Western blot. Results Pharmacologic depletion of B cells did not influence infarct volumes and functional outcome at day 1 after stroke. Additionally, lack of circulating B cells in JHD\(^{-/-}\) mice also failed to influence stroke outcome at days 1 and 3. Furthermore, reconstitution of Rag1\(^{-/-}\) mice with B cells had no influence on infarct volumes. Conclusion Targeting B cells in experimental stroke did not influence lesion volume and functional outcome during the acute phase. Our findings argue against a major pathophysiologic role of B cells during acute ischemic stroke.}, language = {en} } @article{HohnmannMillesSchinkeetal.2014, author = {Hohnmann, Christopher and Milles, Bianca and Schinke, Michael and Schroeter, Michael and Ulzheimer, Jochen and Kraft, Peter and Kleinschnitz, Christoph and Lehmann, Paul V. and Kuerten, Stefanie}, title = {Categorization of multiple sclerosis relapse subtypes by B cell profiling in the blood}, series = {Acta Neuropathologica Communications}, volume = {2}, journal = {Acta Neuropathologica Communications}, number = {138}, doi = {10.1186/s40478-014-0138-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126124}, year = {2014}, abstract = {Introduction B cells are attracting increasing attention in the pathogenesis of multiple sclerosis (MS). B cell-targeted therapies with monoclonal antibodies or plasmapheresis have been shown to be successful in a subset of patients. Here, patients with either relapsing-remitting (n = 24) or secondary progressive (n = 6) MS presenting with an acute clinical relapse were screened for their B cell reactivity to brain antigens and were re-tested three to nine months later. Enzyme-linked immunospot technique (ELISPOT) was used to identify brain-reactive B cells in peripheral blood mononuclear cells (PBMC) directly ex vivo and after 96 h of polyclonal stimulation. Clinical severity of symptoms was determined using the Expanded Disability Status Scale (EDSS). Results Nine patients displayed B cells in the blood producing brain-specific antibodies directly ex vivo. Six patients were classified as B cell positive donors only after polyclonal B cell stimulation. In 15 patients a B cell response to brain antigens was absent. Based on the autoreactive B cell response we categorized MS relapses into three different patterns. Patients who displayed brain-reactive B cell responses both directly ex vivo and after polyclonal stimulation (pattern I) were significantly younger than patients in whom only memory B cell responses were detectable or entirely absent (patterns II and III; p = 0.003). In one patient a conversion to a positive B cell response as measured directly ex vivo and subsequently also after polyclonal stimulation was associated with the development of a clinical relapse. The evaluation of the predictive value of a brain antigen-specific B cell response showed that seven of eight patients (87.5\%) with a pattern I response encountered a clinical relapse during the observation period of 10 months, compared to two of five patients (40\%) with a pattern II and three of 14 patients (21.4\%) with a pattern III response (p = 0.0005; hazard ratio 6.08 (95\% confidence interval 1.87-19.77). Conclusions Our data indicate actively ongoing B cell-mediated immunity against brain antigens in a subset of MS patients that may be causative of clinical relapses and provide new diagnostic and therapeutic options for a subset of patients.}, language = {en} } @article{HohmannMillesSchinkeetal.2014, author = {Hohmann, Christopher and Milles, Bianca and Schinke, Michael and Schroeter, Michael and Ulzheimer, Jochen and Kraft, Peter and Kleinschnitz, Christoph and Lehmann, Paul V. and Kuerten, Stefanie}, title = {Categorization of multiple sclerosis relapse subtypes by B cell profiling in the blood}, series = {Acta Neuropathologica Communications}, volume = {2}, journal = {Acta Neuropathologica Communications}, number = {138}, issn = {2051-5960}, doi = {10.1186/s40478-014-0138-2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120580}, year = {2014}, abstract = {INTRODUCTION: B cells are attracting increasing attention in the pathogenesis of multiple sclerosis (MS). B cell-targeted therapies with monoclonal antibodies or plasmapheresis have been shown to be successful in a subset of patients. Here, patients with either relapsing-remitting (n = 24) or secondary progressive (n = 6) MS presenting with an acute clinical relapse were screened for their B cell reactivity to brain antigens and were re-tested three to nine months later. Enzyme-linked immunospot technique (ELISPOT) was used to identify brain-reactive B cells in peripheral blood mononuclear cells (PBMC) directly ex vivo and after 96 h of polyclonal stimulation. Clinical severity of symptoms was determined using the Expanded Disability Status Scale (EDSS). RESULTS: Nine patients displayed B cells in the blood producing brain-specific antibodies directly ex vivo. Six patients were classified as B cell positive donors only after polyclonal B cell stimulation. In 15 patients a B cell response to brain antigens was absent. Based on the autoreactive B cell response we categorized MS relapses into three different patterns. Patients who displayed brain-reactive B cell responses both directly ex vivo and after polyclonal stimulation (pattern I) were significantly younger than patients in whom only memory B cell responses were detectable or entirely absent (patterns II and III; p = 0.003). In one patient a conversion to a positive B cell response as measured directly ex vivo and subsequently also after polyclonal stimulation was associated with the development of a clinical relapse. The evaluation of the predictive value of a brain antigen-specific B cell response showed that seven of eight patients (87.5\%) with a pattern I response encountered a clinical relapse during the observation period of 10 months, compared to two of five patients (40\%) with a pattern II and three of 14 patients (21.4\%) with a pattern III response (p = 0.0005; hazard ratio 6.08 (95\% confidence interval 1.87-19.77). CONCLUSIONS: Our data indicate actively ongoing B cell-mediated immunity against brain antigens in a subset of MS patients that may be causative of clinical relapses and provide new diagnostic and therapeutic options for a subset of patients.}, language = {en} } @article{DirksFischerHaaseetal.2021, author = {Dirks, Johannes and Fischer, Jonas and Haase, Gabriele and Holl-Wieden, Annette and Hofmann, Christine and Girschick, Hermann and Morbach, Henner}, title = {CD21\(^{lo/-}\)CD27\(^-\)IgM\(^-\) Double-Negative B Cells Accumulate in the Joints of Patients With Antinuclear Antibody-Positive Juvenile Idiopathic Arthritis}, series = {Frontiers in Pediatrics}, volume = {9}, journal = {Frontiers in Pediatrics}, issn = {2296-2360}, doi = {10.3389/fped.2021.635815}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236286}, year = {2021}, abstract = {Juvenile idiopathic arthritis (JIA) encompasses a heterogeneous group of diseases. The appearance of antinuclear antibodies (ANAs) in almost half of the patients suggests B cell dysregulation as a distinct pathomechanism in these patients. Additionally, ANAs were considered potential biomarkers encompassing a clinically homogenous subgroup of JIA patients. However, in ANA+ JIA patients, the site of dysregulated B cell activation as well as the B cell subsets involved in this process is still unknown. Hence, in this cross-sectional study, we aimed in an explorative approach at characterizing potential divergences in B cell differentiation in ANA+ JIA patients by assessing the distribution of peripheral blood (PB) and synovial fluid (SF) B cell subpopulations using flow cytometry. The frequency of transitional as well as switched-memory B cells was higher in PB of JIA patients than in healthy controls. There were no differences in the distribution of B cell subsets between ANA- and ANA+ patients in PB. However, the composition of SF B cells was different between ANA- and ANA+ patients with increased frequencies of CD21\(^{lo/-}\)CD27\(^-\)IgM\(^-\) "double negative" (DN) B cells in the latter. DN B cells might be a characteristic subset expanding in the joints of ANA+ JIA patients and are potentially involved in the antinuclear immune response in these patients. The results of our explorative study might foster further research dissecting the pathogenesis of ANA+ JIA patients.}, language = {en} } @article{WunschZhangHansonetal.2015, author = {Wunsch, Marie and Zhang, Wenji and Hanson, Jodi and Caspell, Richard and Karulin, Alexey Y. and Recks, Mascha S. and Kuerten, Stefanie and Sundararaman, Srividya and Lehmann, Paul V.}, title = {Characterization of the HCMV-Specific CD4 T Cell Responses that Are Associated with Protective Immunity}, series = {Viruses}, volume = {7}, journal = {Viruses}, doi = {10.3390/v7082828}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151462}, pages = {4414 -- 4437}, year = {2015}, abstract = {Most humans become infected with human cytomegalovirus (HCMV). Typically, the immune system controls the infection, but the virus persists and can reactivate in states of immunodeficiency. While substantial information is available on the contribution of CD8 T cells and antibodies to anti-HCMV immunity, studies of the T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 subsets have been limited by the low frequency of HCMV-specific CD4 T cells in peripheral blood mononuclear cell (PBMC). Using the enzyme-linked Immunospot\(^{®}\) assay (ELISPOT) that excels in low frequency measurements, we have established these in a sizable cohort of healthy HCMV controllers. Cytokine recall responses were seen in all seropositive donors. Specifically, interferon (IFN)-\({\gamma}\) and/or interleukin (IL)-17 were seen in isolation or with IL-4 in all test subjects. IL-4 recall did not occur in isolation. While the ratios of T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 cells exhibited substantial variations between different individuals these ratios and the frequencies were relatively stable when tested in samples drawn up to five years apart. IFN-\({\gamma}\) and IL-2 co-expressing polyfunctional cells were seen in most subjects. Around half of the HCMV-specific CD4 cells were in a reversible state of exhaustion. The data provided here established the T\(_{H}\)1, T\(_{H}\)2, and T\(_{H}\)17 characteristic of the CD4 cells that convey immune protection for successful immune surveillance against which reactivity can be compared when the immune surveillance of HCMV fails.}, language = {en} } @article{ArndtHoffackerZellmeretal.2014, author = {Arndt, Andreas and Hoffacker, Peter and Zellmer, Konstantin and Goecer, Oktay and Recks, Mascha S. and Kuerten, Stefanie}, title = {Conventional Housing Conditions Attenuate the Development of Experimental Autoimmune Encephalomyelitis}, series = {PLoS ONE}, volume = {9}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0099794}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119603}, pages = {e99794}, year = {2014}, abstract = {BACKGROUND: The etiology of multiple sclerosis (MS) has remained unclear, but a causative contribution of factors outside the central nervous system (CNS) is conceivable. It was recently suggested that gut bacteria trigger the activation of CNS-reactive T cells and the development of demyelinative disease. METHODS: C57BL/6 (B6) mice were kept either under specific pathogen free or conventional housing conditions, immunized with the myelin basic protein (MBP)-proteolipid protein (PLP) fusion protein MP4 and the development of EAE was clinically monitored. The germinal center size of the Peyer's patches was determined by immunohistochemistry in addition to the level of total IgG secretion which was assessed by ELISPOT. ELISPOT assays were also used to measure MP4-specific T cell and B cell responses in the Peyer's patches and the spleen. Ear swelling assays were performed to determine the extent of delayed-type hypersensitivity reactions in specific pathogen free and conventionally housed mice. RESULTS: In B6 mice that were actively immunized with MP4 and kept under conventional housing conditions clinical disease was significantly attenuated compared to specific pathogen free mice. Conventionally housed mice displayed increased levels of IgG secretion in the Peyer's patches, while the germinal center formation in the gut and the MP4-specific TH17 response in the spleen were diminished after immunization. Accordingly, these mice displayed an attenuated delayed type hypersensitivity (DTH) reaction in ear swelling assays. CONCLUSIONS: The data corroborate the notion that housing conditions play a substantial role in the induction of murine EAE and suggest that the presence of gut bacteria might be associated with a decreased immune response to antigens of lower affinity. This concept could be of importance for MS and calls for caution when considering the therapeutic approach to treat patients with antibiotics."}, language = {en} } @article{KaderAzeemJwayedetal.2021, author = {Kader, Hidaya A. and Azeem, Muhammad and Jwayed, Suhib A. and Al-Shehhi, Aaesha and Tabassum, Attia and Ayoub, Mohammed Akli and Hetta, Helal F. and Waheed, Yasir and Iratni, Rabah and Al-Dhaheri, Ahmed and Muhammad, Khalid}, title = {Current insights into immunology and novel therapeutics of atopic dermatitis}, series = {Cells}, volume = {10}, journal = {Cells}, number = {6}, issn = {2073-4409}, doi = {10.3390/cells10061392}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241008}, year = {2021}, abstract = {Atopic dermatitis (AD) is one of the most prevalent inflammatory disease among non-fatal skin diseases, affecting up to one fifth of the population in developed countries. AD is characterized by recurrent pruritic and localized eczema with seasonal fluctuations. AD initializes the phenomenon of atopic march, during which infant AD patients are predisposed to progressive secondary allergies such as allergic rhinitis, asthma, and food allergies. The pathophysiology of AD is complex; onset of the disease is caused by several factors, including strong genetic predisposition, disrupted epidermal barrier, and immune dysregulation. AD was initially characterized by defects in the innate immune system and a vigorous skewed adaptive Th2 response to environmental agents; there are compelling evidences that the disorder involves multiple immune pathways. Symptomatic palliative treatment is the only strategy to manage the disease and restore skin integrity. Researchers are trying to more precisely define the contribution of different AD genotypes and elucidate the role of various immune axes. In this review, we have summarized the current knowledge about the roles of innate and adaptive immune responsive cells in AD. In addition, current and novel treatment strategies for the management of AD are comprehensively described, including some ongoing clinical trials and promising therapeutic agents. This information will provide an asset towards identifying personalized targets for better therapeutic outcomes.}, language = {en} }