688 research outputs found
Politische Parteien und Parteiensystem in Benin
No full text[Jan Niklas Engels]Electronic ed.: Bonn : FES Library, 2008. - Title only available onlin
The Memory Function of the B Cell Antigen Receptor
No full textActivated B lymphocytes preserve their antigen experience by differentiating into long-lived pools of antibody-secreting plasma cells or various types of memory B cells (MBCs). The former population constantly produces serum immunoglobulins with sufficient specificity and affinity to thwart infections with recurrent pathogens. By contrast, memory B cell populations retain their antigen receptors on the cell surface and hence need pathogen-induced differentiation steps before they can actively contribute to host defense. The terminal differentiation of MBCs into antibody-secreting plasma cells is hallmarked by the absence of the lag phase characteristic for primary antibody responses. Moreover, secondary antibody responses are predominantly driven by MBCs that bear an antigen receptor of the IgG class on their surface although IgM-positive memory populations exist as well. These fundamental principles of B cell memory were enigmatic for decades. Only recently, we have begun to understand the underlying mechanisms. This review summarizes our current understanding of how different subpopulations of MBCs are generated during primary immune responses and how their functional heterogeneity on antigen recall is controlled by different signaling capabilities of B cell antigen receptor (BCR) isotypes and by the nature of the antigen
International politics and society / The new promise of happiness : current state of the discussion on the future of European social democracy
No full textJan Niklas Engels ; Gero MaassElectronic ed.: Berlin : IPG-Redaktion, 201
The signaling tool box for tyrosine-based costimulation of lymphocytes
No full textTriggering lymphocyte effector functions is controlled by a diverse array of immune cell coreceptors that dampen or potentiate the primary activation signal from antigen receptors. Attenuation of lymphocyte activation has been shown to be accomplished by immunoreceptor tyrosine-based inhibition motifs that upon phosphorylation recruit protein or lipid phosphatases. By contrast, a general concept of signal amplification and/or diversification is still out. However, the recent discovery of antigen receptor-intrinsic costimulation by membrane-bound immunoglobulins in class-switched memory B cells identified a consensus phosphorylation motif that can boost antigen-induced signal chains and is also employed by costimulatory receptors on T and Natural Killer cells to provide secondary signals for cellular activation. Here we define a common basis of tyrosine-based lymphocyte costimulation comprising immunoglobulin tail tyrosine (ITT)-like phosphorylation motifs and their proximal effectors, growth factor receptor-bound protein (Grb) 2 and phosphatidylinositol-3 kinase (PI3K) enzymes of class IA
Das neue Glücksversprechen : Zwischenbilanz der Diskussion über die Zukunft der europäischen Sozialdemokratie
No full textJan Niklas Engels ; Gero MaaßElectronic ed.: Berlin ; Bonn : FES, 2010. - Title only available onlin
Analyse der Bundestagswahl 2025 : eine harte Niederlage mit einer doppelten Herausforderung für die Sozialdemokratie
No full textCatrina Schläger, Jan Niklas Engels, Nicole Loew ; Herausgebende Abteilung: Abteilung Analyse, Planung und Beratun
Wie viel Klasse steckt in der Mitte? : Erwerbsklassen und ihr Blick auf Arbeit, Gesellschaft und Politik
No full textJan Niklas Engels, Annika Arnold und Catrina Schläger ; Herausgeberin: Abteilung, Planung und Beratun
Analyse der Bundestagswahl 2025
No full textCatrina Schläger, Jan Niklas Engels, Nicole Loew ; publishing department: Analysis and Planning Department ; translation James Patterso
- …
