New perspectives on the evolution of B-lymphocytes in germinal centers [Elektronische Ressource] / von Nicole Wittenbrink

New perspectives on the evolution ofB-lymphocytes in germinal centersDISSERTATIONzur Erlangung des akademischen Gradesdoctor rerum naturalium(Dr. rer. nat.)im Fach Biologieeingereicht an derMathematisch-Naturwissenschaftlichen Fakultät IHumboldt-Universität zu BerlinvonFrau Dipl.-Ing. Nicole Wittenbrinkgeboren am 19.08.1975 in GüterslohPräsident der Humboldt-Universität zu Berlin:Prof. Dr. Christoph MarkschiesDekan der Mathematisch-Naturwissenschaftlichen Fakultät I:Prof. Dr. Christian LimbergGutachter:1. Dr. Michal Or-Guil2. PD Dr. Rudolf Manz3. Prof. Dr. Hans-Dieter Volkeingereicht am: 21. Mai 2007Tag der mündlichen Prüfung: 21. November 2007One cannot divine nor forcast the conditions that will make happiness; one onlystumbles upon them by chance, in a lucky hour, at the world’s end somewhere, andholds fast to the days, as to fortune or fame.Willa Cather, Le Levandou, 1902AbstractCentral to the humoral immune response is the commonly observed improvement ofantibody affinity over time, a phenomenon referred to as affinity maturation.Affinitymaturationtakesplaceinso-calledgerminalcenters (GC)thataretran-siently formed in secondary lymphoid tissues (e.g. spleen) following immunizationwith T cell-dependent antigens.