@article{MahmoodSchmalzingDoerneretal.2020,
  author    = {Mahmood, Zafar and Schmalzing, Marc and D{\"o}rner, Thomas and Tony, Hans-Peter and Muhammad, Khalid},
  title     = {Therapeutic Cytokine Inhibition Modulates Activation and Homing Receptors of Peripheral Memory B Cell Subsets in Rheumatoid Arthritis Patients},
  series = {Frontiers in Immunology},
  volume    = {11},
  journal   = {Frontiers in Immunology},
  issn      = {1664-3224},
  doi       = {10.3389/fimmu.2020.572475},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-212380},
  year      = {2020},
  abstract  = {Memory B cells have known to play an important role in the pathogenesis of rheumatoid arthritis (RA). With the emergence of B cell-targeted therapies, the modulation of memory B cells appears to be a key therapeutic target. Human peripheral memory B cells can be distinguished based on the phenotypic expression of CD27 and IgD, characterizing the three major B cell subpopulations: CD27+IgD+ pre-switch, CD27+IgD- post-switch, and CD27-IgD- double-negative memory B cells. We evaluated different memory cell populations for activation markers (CD95 and Ki-67) and chemokine receptors (CXCR3 and 4) expressing B cells in active RA, as well as under IL6-R blockade by tocilizumab (TCZ) and TNF-α blockade by adalimumab (ADA). Memory B cells were phenotypically analyzed from RA patients at baseline, week 12, and week 24 under TCZ or ADA treatment, respectively. Using flow cytometry, surface expression of CD95, intracellular Ki-67, and surface expressions of CXCR3 and CXCR4 were determined. Compared with healthy donors (n = 40), the phenotypic analysis of RA patients (n = 80) demonstrated that all three types of memory B cells were activated in RA patients. Surface and intracellular staining of B cells showed a significantly higher percentage of CD95+ (p < 0.0001) and Ki-67+ (p < 0.0001) cells, with numerically altered CXCR3+ and CXCR4+ cells in RA. CD95 and Ki-67 expressions were highest in post-switch memory B cells, whereas CD19+CXCR3+ and CD19+CXCR4+ expressing cells were substantially higher in the pre-switch compartment. In all subsets of the memory B cells, in vivo IL-6R, and TNF-α blockade significantly reduced the enhanced expressions of CD95 and Ki-67. Based on our findings, we conclude that the three major peripheral memory B cell populations, pre-, post-switch, and double-negative B cells, are activated in RA, demonstrating enhanced CD95 and Ki-67 expressions, and varied expression of CXCR3 and CXCR4 chemokine receptors when compared with healthy individuals. This activation can be efficaciously modulated under cytokine inhibition in vivo.},
  language  = {en}
}
@article{SanchezMaldonadoMonizDiezterHorstetal.2020,
  author    = {S{\´a}nchez-Maldonado, Jose Manuel and Mo{\~n}iz-D{\´i}ez, Ana and ter Horst, Rob and Campa, Daniele and Cabrera-Serrano, Antonio Jos{\´e} and Mart{\´i}nez-Bueno, Manuel and Garrido-Collado, Mar{\´i}a del Pilar and Hern{\´a}ndez-Mohedo, Francisca and Fern{\´a}ndez-Puerta, Laura and L{\´o}pez-Nevot, Miguel {\´A}ngel and Cunha, Cristina and Gonz{\´a}lez-Sierra, Pedro Antonio and Springer, Jan and Lackner, Michaela and Alcazar-Fuoli, Laura and Fianchi, Luana and Aguado, Jos{\´e} Mar{\´i}a and Pagano, Livio and L{\´o}pez-Fern{\´a}ndez, Elisa and Clavero, Esther and Potenza, Leonardo and Luppi, Mario and Moratalla, Lucia and Solano, Carlos and Sampedro, Antonio and Cuenca-Estrella, Manuel and Lass-Fl{\"o}rl, Cornelia and Canzian, Federico and Loeffler, Juergen and Li, Yang and Einsele, Hermann and Netea, Mihai G. and V{\´a}zquez, Lourdes and Carvalho, Agostinho and Jurado, Manuel and Sainz, Juan},
  title     = {Polymorphisms within the TNFSF4 and MAPKAPK2 loci influence the risk of developing invasive aspergillosis: a two-stage case control study in the context of the aspBIOmics consortium},
  series = {Journal of Fungi},
  volume    = {7},
  journal   = {Journal of Fungi},
  number    = {1},
  issn      = {2309-608X},
  doi       = {10.3390/jof7010004},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220107},
  year      = {2020},
  abstract  = {Here, we assessed whether 36 single nucleotide polymorphisms (SNPs) within the TNFSF4 and MAPKAPK2 loci influence the risk of developing invasive aspergillosis (IA). We conducted a two-stage case control study including 911 high-risk patients diagnosed with hematological malignancies that were ascertained through the aspBIOmics consortium. The meta-analysis of the discovery and replication populations revealed that carriers of the TNFSF4\(_{rs7526628T/T}\) genotype had a significantly increased risk of developing IA (p = 0.00022). We also found that carriers of the TNFSF4\(_{rs7526628T}\) allele showed decreased serum levels of TNFSF14 protein (p = 0.0027), and that their macrophages had a decreased fungicidal activity (p = 0.048). In addition, we observed that each copy of the MAPKAPK2\(_{rs12137965G}\) allele increased the risk of IA by 60\% (p = 0.0017), whereas each copy of the MAPKAPK2\(_{rs17013271T}\) allele was estimated to decrease the risk of developing the disease (p = 0.0029). Mechanistically, we found that carriers of the risk MAPKAPK2\(_{rs12137965G}\) allele showed increased numbers of CD38+IgM-IgD- plasmablasts in blood (p = 0.00086), whereas those harboring two copies of the allele had decreased serum concentrations of thymic stromal lymphopoietin (p = 0.00097). Finally, we also found that carriers of the protective MAPKAPK2\(_{rs17013271T}\) allele had decreased numbers of CD27-IgM-IgD- B cells (p = 0.00087) and significantly lower numbers of CD14+ and CD14+CD16- cells (p = 0.00018 and 0.00023). Altogether, these results suggest a role of the TNFSF4 and MAPKAPK2 genes in determining IA risk.},
  language  = {en}
}
@article{BeilhackChopraKrausetal.2013,
  author    = {Beilhack, Andreas and Chopra, Martin and Kraus, Sabrina and Schwinn, Stefanie and Ritz, Miriam and Mattenheimer, Katharina and Mottok, Anja and Rosenwald, Andreas and Einsele, Hermann},
  title     = {Non-Invasive Bioluminescence Imaging to Monitor the Immunological Control of a Plasmablastic Lymphoma-Like B Cell Neoplasia after Hematopoietic Cell Transplantation},
  doi       = {10.1371/journal.pone.0081320},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111341},
  year      = {2013},
  abstract  = {To promote cancer research and to develop innovative therapies, refined pre-clinical mouse tumor models that mimic the actual disease in humans are of dire need. A number of neoplasms along the B cell lineage are commonly initiated by a translocation recombining c-myc with the immunoglobulin heavy-chain gene locus. The translocation is modeled in the C.129S1-Ighatm1(Myc)Janz/J mouse which has been previously engineered to express c-myc under the control of the endogenous IgH promoter. This transgenic mouse exhibits B cell hyperplasia and develops diverse B cell tumors. We have isolated tumor cells from the spleen of a C.129S1-Ighatm1(Myc)Janz/J mouse that spontaneously developed a plasmablastic lymphoma-like disease. These cells were cultured, transduced to express eGFP and firefly luciferase, and gave rise to a highly aggressive, transplantable B cell lymphoma cell line, termed IM380. This model bears several advantages over other models as it is genetically induced and mimics the translocation that is detectable in a number of human B cell lymphomas. The growth of the tumor cells, their dissemination, and response to treatment within immunocompetent hosts can be imaged non-invasively in vivo due to their expression of firefly luciferase. IM380 cells are radioresistant in vivo and mice with established tumors can be allogeneically transplanted to analyze graft-versus-tumor effects of transplanted T cells. Allogeneic hematopoietic stem cell transplantation of tumor-bearing mice results in prolonged survival. These traits make the IM380 model very valuable for the study of B cell lymphoma pathophysiology and for the development of innovative cancer therapies.},
  language  = {en}
}
@article{GernertTonySchwanecketal.2020,
  author    = {Gernert, Michael and Tony, Hans-Peter and Schwaneck, Eva Christina and Fr{\"o}hlich, Matthias and Schmalzing, Marc},
  title     = {Low B cell counts as risk factor for infectious complications in systemic sclerosis after autologous hematopoietic stem cell transplantation},
  series = {Arthritis Research \& Therapy},
  volume    = {22},
  journal   = {Arthritis Research \& Therapy},
  doi       = {10.1186/s13075-020-02255-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229962},
  year      = {2020},
  abstract  = {Background Autologous hematopoietic stem cell transplantation (aHSCT) is a treatment option for a selected group of systemic sclerosis (SSc) patients with good available evidence but can be associated with considerable morbidity and mortality. The aim of this study was to describe infectious complications and distinct immune reconstitution patterns after aHSCT and to detect risk factors in lymphocyte subsets, which are associated with an elevated rate of infections after aHSCT. Methods Seventeen patients with SSc were included in this single-center retrospective cohort study. Clinical and laboratory data was collected before and for 12 months after aHSCT, including immunophenotyping of peripheral whole blood by fluorescence-activated cell sorting. Results Cytomegalovirus (CMV) reactivations were common in CMV-IgG-positive patients (50\%) and needed treatment. Mycotic infections occurred in 17.6\%. One patient died (resulting in a mortality of 5.9\%) due to pneumonia with consecutive sepsis. All patients showed decreased T helper cells (CD3\(^+\)/CD4\(^+\)) and within the B cell compartment decreased post-switched memory B cells (CD19\(^+\)/CD27\(^+\)/IgD\(^-\)) and elevated naive B cells (CD19\(^+\)/CD27\(^-\)/IgD\(^+\)) until 12 months after aHSCT. Patients who developed infections had significantly lower B cells before aHSCT than patients who did not develop infections. Conclusion After aHSCT, monitoring for infectious complications, especially for CMV reactivations, is crucial as the reconstitution of the immune system takes longer than 12 months. Low peripheral B cells might be a risk factor for an elevated infection rate.},
  language  = {en}
}
@phdthesis{Palanichamy2007,
  author    = {Palanichamy, Arumugam},
  title     = {Influence of transient B cell depletion on recirculating B cells and plasma cells in rheumatoid arthritis},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-25132},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2007},
  abstract  = {Die zentrale Rolle der B-Zellen in der Pathogenese von Autoimmunerkrankungen hat in den letzten Jahren zu unterschiedlichen therapeutischen Ans{\"a}tzen gef{\"u}hrt, B-Zellen direkt oder indirekt zu targetieren. Ein Beispiel hierf{\"u}r stellt der monoklonale anti-CD20 Antik{\"o}rper Rituximab dar. Derzeit ist wenig {\"u}ber das Regenerationsverhalten von B-Zellen nach Therapie mit Rituximab bekannt. Daher untersuchten wir die fr{\"u}he Regnerationsphase und die Ver{\"a}nderungen des B-Zellrepertoirs. Am Beispiel der VH4 Familie der Immunglobulin schweren Ketten analysierten wir die Modulation des Immunglobulinrezeptor Repertoires durch die passagere B-Zelldepletion. Insgesamt wurden bei 5 Patienten 3 Zeitpunkte analysiert: vor Therapie, in der fr{\"u}hen Regenerationsphase (ERP- early regeneration period, mit einem B-Zellanteil > 1\% im peripheren Blut) und in der sp{\"a}ten Regenerationsphase (LRP- late regeneration period, 2-3 Monate nach der fr{\"u}hen Regenerationsphase). Bei 3 Patienten (A-C) wurden die Ig-VH4 Gene aus genomischer DNA amplifiziert und zu o.g. Zeitpunkten analysiert. Bei weiteren 2 Patienten (D und E) erfolgte die Analyse der Ig Gene in einzelnen B-Zellen mittels Einzelzellsortierung und Einzelzell RT-PCR. Die B-Zellregeneration nach Therapie mit Rituximab zeigte ein charakteristisches Regenerationsmuster mit einer Dominanz von unreifen CD10+ B-Zellen und CD38hi Plasmazellen w{\"a}hrend der fr{\"u}hen Phase der B-Zellrekonstitution. Im weiteren Verlauf kam es zu einer Abnahme dieser Zellen und einem Anstieg von naiven B-Zellen. Auf der molekularen Ebene zeigte sich vor und nach B-Zelldepletion eine unterschiedliche Nutzung der Ig-VH4 Gene. Mini Gene wie VH4-34 und VH4-39, die in Verbindung mit Autoimmunit{\"a}t stehen, waren vor Einleitung der Therapie {\"u}berexprimiert. Durch die Behandlung mit Rituximab kam es zu einer Ver{\"a}nderung des Repertoires der regenerierenden B-Zellen mit einer reduzierten Benutzung der VH4-39 Gene im B-Zellpool. Tief greifende Ver{\"a}nderungen fanden sich im regenerierenden Repertoire, mit einem relativen Anstieg von stark mutierten (>=9 Mutationen / Ig Sequenz) B-Zellen.. Die Immunph{\"a}notypisierung zeigte, dass diese hochmutierten B-Zellen den Ig-klassengeswitchten Ged{\"a}chtnis B-Zellkompartiment, insbesondere den Plasmazellen zugh{\"o}rig sind. Um diese Hypothese zu untermauern, erfolgte bei 2 Patienten eine Einzelzellsortierung dieser Plasmazellen w{\"a}hrend der fr{\"u}hen Regenerationsphase, welche einen vergleichbaren Mutationsstatus zeigte. Da Plasmazellen kein CD20 Molek{\"u}l exprimieren, werden sie durch eine Therapie mit Rituximab nicht direkt eliminiert. Allerdings zirkulieren sie nicht im peripheren Blut w{\"a}hrend der Phase der B-Zelldepletion. W{\"a}hrend der fr{\"u}hen Regenerationsphase (ERP) lassen sie sich in der Peripherie erneut nachweisen. Es wurde deshalb untersucht ob auch Plasmazellen durch die Therapie moduliert werden, obwohl sie nicht direkt durch Rituximab targetiert werden. In diesem Zusammenhang erfolgte eine detaillierte Analyse des Mutationsmusters der Plasmazellen vor Therapie und w{\"a}hrend der fr{\"u}hen Regenerationsphase. Die Analyse der Mutationsh{\"a}ufigkeit in RGYW/WRCY Hotspot Motive (R=purine, Y=pyrimidine, W=A/T) erlaubt Absch{\"a}tzung in wieweit die somatische Hypermutation der B-Zellen durch T-Zell abh{\"a}ngige Differenzierung erfolgte. Die Plasmazellen vor Therapie zeigten einem verminderten Targeting der RGYW/WRCY Motive. Im Gegensatz hierzu zeigte sich in den rezirkulierenden Plasmazellen w{\"a}hrend der fr{\"u}hen Regenerationsphase ein zunehmendes Targeting der RGYW/WRCY Motive. Dies spricht f{\"u}r einen Repertoire Shift zu mehr T-Zellabh{\"a}ngigen B-Zell Mutation. Ein Zusatand, wie er bei Gesunden beobachtet wird. Um die Hypothese der Rituximab-induzierten Plasmazell Modulation zu st{\"u}tzen wurde die R/S- Ratio (replacement to silent mutations ratio) der hypervariablen Regionen (CDRs) der Plasmazell Ig Sequenzen bestimmt. In unserer Studie war die mittlere R/S Ratio der CDRs der Plasmazellen vor Therapie entsprechend relativ niedrig (1.87). Interessanterweise kam es in der fr{\"u}hen und sp{\"a}ten Regenerationsphase zu einer signifikant erh{\"o}hten R/S Ration in den rezirkulierenden Plasmazellen mit Werten von 2.67 bzw. 3.60. Die verminderte R/S Ratio in den CDRs der Plasmazellen kann als Entwicklung des Ig-Repertoires durch positive Antigenselektion interpretiert werden und weist damit eine Therapie induzierte Ver{\"a}nderung auf, die dem entspricht wie man sie bei Gesunden findet. Zusammenfassend zeigt unsere Studie, dass die passagere B-Zelldepletion mit Rituximab zu einer Modulation des Plasmalzellkompartimentes f{\"u}hrt, welches nicht direkt durch die Therapie targetiert wird. Die Modulation der Plasmazellen bei der RA kann eventuell auch als m{\"o}glicher Biomarker entwickelt werden, um ein Ansprechen auf die Therapie vorherzusagen. Dies muss im Weiteren untersucht werden, um tiefer greifende Einblicke in Prozesse zu erlangen, die durch zuk{\"u}nftige Therapien beeinflussbar werden.},
  subject      = {B-zellen},
  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}
}