title: Regulation of memory antibody levels: the role of persisting antigen versus plasma cell life span.
abstract: Protective Ab levels can be maintained for years upon infection or vaccination. In this study, we studied the duration of Ab responses as a function of the life span of plasma cells and tested the role of persisting Ag in maintaining B cell memory. Our analysis of B cell responses induced in mice immunized with virus-like particles demonstrates the following: 1) Ab titers are long-lived, but decline continuously with a t(1/2) of approximately 80 days, which corresponds to the life span of plasma cells; 2) the germinal center (GC) reaction, which lasts for up to 100 days, is dependent on Ag associated with follicular dendritic cells; and 3) early GCs produce massive numbers of plasma and memory B cell precursors, whereas the late Ag-dependent GCs are dispensable for the maintenance of Ab levels and B cell memory.
authors.affiliation: Cytos Biotechnology, Zurich-Schlieren, Switzerland.
authors.forename: Dominique
authors.initials: D
authors.lastname: Gatto
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Martin
authors.forename: Juliana
authors.initials: J
authors.lastname: Bessa
authors.forename: Erica
authors.initials: E
authors.lastname: Pellicioli
authors.forename: Philippe
authors.initials: P
authors.lastname: Saudan
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Hinton
authors.forename: Martin F
authors.initials: MF
authors.lastname: Bachmann
mesh_terms: D017908:Allolevivirus / Q000276:immunology; D000818:Animals; D000906:Antibodies / Q000097:blood*; D000941:Antigens / Q000097:blood / Q000276:immunology*; D049109:Cell Proliferation; D020566:Dendritic Cells, Follicular / Q000187:drug effects / Q000276:immunology; D018858:Germinal Center / Q000166:cytology / Q000276:immunology; D007114:Immunization; D007136:Immunoglobulins / Q000494:pharmacology; D007156:Immunologic Memory; D007165:Immunosuppression Therapy; D007700:Kinetics; D053259:Lymphotoxin beta Receptor / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D010950:Plasma Cells / Q000166:cytology / Q000276:immunology*; D014771:Virion / Q000276:immunology
chemical_list: D000906:Antibodies; D000941:Antigens; D007136:Immunoglobulins; D053259:Lymphotoxin beta Receptor