@article{WunschHohmannMillesetal.2016, author = {Wunsch, Marie and Hohmann, Christopher and Milles, Bianca and Rostermund, Christina and Lehmann, Paul V. and Schroeter, Michael and Bayas, Antonios and Ulzheimer, Jochen and M{\"a}urer, Mathias and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie}, title = {The Correlation between the Virus- and Brain Antigen-Specific B Cell Response in the Blood of Patients with Multiple Sclerosis}, series = {Viruses}, volume = {8}, journal = {Viruses}, number = {4}, doi = {10.3390/v8040105}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146946}, pages = {105}, year = {2016}, abstract = {There is a largely divergent body of literature regarding the relationship between Epstein-Barr virus (EBV) infection and brain inflammation in multiple sclerosis (MS). Here, we tested MS patients during relapse (n = 11) and in remission (n = 19) in addition to n = 22 healthy controls to study the correlation between the EBV- and brain-specific B cell response in the blood by enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). Cytomegalovirus (CMV) was used as a control antigen tested in n = 16 MS patients during relapse and in n = 35 patients in remission. Over the course of the study, n = 16 patients were untreated, while n = 33 patients received immunomodulatory therapy. The data show that there was a moderate correlation between the frequencies of EBV- and brain-reactive B cells in MS patients in remission. In addition we could detect a correlation between the B cell response to EBV and disease activity. There was no evidence of an EBV reactivation. Interestingly, there was also a correlation between the frequencies of CMV- and brain-specific B cells in MS patients experiencing an acute relapse and an elevated B cell response to CMV was associated with higher disease activity. The trend remained when excluding seronegative subjects but was non-significant. These data underline that viral infections might impact the immunopathology of MS, but the exact link between the two entities remains subject of controversy.}, language = {en} } @article{RovitusoSchefflerWunschetal.2016, author = {Rovituso, Damiano M. and Scheffler, Laura and Wunsch, Marie and Kleinschnitz, Christoph and D{\"o}rck, Sebastian and Ulzheimer, Jochen and Bayas, Antonios and Steinman, Lawrence and Erg{\"u}n, S{\"u}leyman and Kuerten, Stefanie}, title = {CEACAM1 mediates B cell aggregation in central nervous system autoimmunity}, series = {Scientific Reports}, volume = {6}, journal = {Scientific Reports}, doi = {10.1038/srep29847}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-147690}, pages = {29847}, year = {2016}, abstract = {B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1\(^+\) B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain -3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease.}, 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} } @phdthesis{Ulzheimer2003, author = {Ulzheimer, Jochen C.}, title = {Funktionelle Charakterisierung der Transportproteine f{\"u}r Organische Kationen rOCT1 und hOCT2 unter besonderer Ber{\"u}cksichtigung der cis-/trans-Asymmetrie von rOCT1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-6444}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2003}, abstract = {rOCT1 und hOCT2 sind zwei homologe Transportproteine f{\"u}r organische Kationen, die in Niere und Leber den ersten Schritt der transepithelialen Sekretion von Metaboliten und Xenobiotika vermitteln. Eines ihrer wesentlichen Charakteristika ist neben der Potentialabh{\"a}ngigkeit die Polyspezifit{\"a}t hinsichtlich Transportsubstraten und Hemmstoffen. Beide Transporter k{\"o}nnen als Uniporter klassifiziert werden, d.h. sie besitzen keine obligate Kopplung an ein Austausch- oder Cosubstrat wie z.B. Natrium, Protonen oder andere organische Kationen. Dar{\"u}berhinaus zeigen sie das f{\"u}r Transportproteine typische und von Kan{\"a}len distinkte Charakteristikum der trans-Stimulierbarkeit. Mit rOCT1 konnten erstmals f{\"u}r einen Prototypen der Transportersuperfamilie SLC22 n{\"a}here Aufschl{\"u}sse {\"u}ber den Transportmechanismus erhalten werden. Zum einen wurde nachgewiesen, daß rOCT1 eine direktionale Asymmetrie besitzt, d.h. unter S{\"a}ttigungsbedingungen besteht eine kinetische Bevorzugung der Transportrichtung von extra- nach intrazellul{\"a}r um den Faktor zwei bis f{\"u}nf. Zum anderen wurden anhand von rOCT1 neue Erkenntnisse zum Bindungs- und Interaktionsverhalten von Hemmstoffen und Transportsubstraten in Abh{\"a}ngigkeit von der Transportrichtung gewonnen. Hierbei erscheint das bisherige Modell von topologisch festgelegter kompetitiver und allosterischer Hemmung zu stark vereinfacht und nicht zutreffend. Die Bindung von Transportsubstraten und die dadurch induzierten Konformations{\"a}nderungen scheinen selbst die Bindungseigenschaften von Hemmstoffen in mehreren Zust{\"a}nden zu beeinflussen. Auch scheinen Transport- und Ionenleitf{\"a}higkeit von OCT zu differenzieren zu sein. Zur Kl{\"a}rung der Fragestellungen wurde das Expressionsmodell Xenopus-Oozyte durch die Etablierung der sogenannten Effluxmethodik funktionell und methodisch wesentlich erweitert.}, language = {de} }