Multiple layers of B cell memory with different effector functions.
Memory B cells are at the center of longstanding controversies regarding the presence of antigen for their survival and their re-engagement in germinal centers after secondary challenge. Using a new mouse model of memory B cell labeling dependent on the cytidine deaminase AID, we show that after immunization with a particulate antigen, B cell memory appeared in several subsets, comprising clusters of immunoglobulin M-positive (IgM(+)) and IgG1(+) B cells in germinal center-like structures that persisted up to 8 months after immunization, as well as IgM(+) and IgG1(+) B cells with a memory phenotype outside of B cell follicles. After challenge, the IgG subset differentiated into plasmocytes, whereas the IgM subset reinitiated a germinal center reaction. This model, in which B cell memory appears in several layers with different functions, reconciles previous conflicting propositions.
Institut National de la Santé et de la Recherche Médicale U783 'Développement du système immunitaire', Université Paris Descartes, Faculté de Médecine, Site Necker-Enfants Malades, Paris, France.
Ismail
I
Dogan
Barbara
B
Bertocci
Valérie
V
Vilmont
Frédéric
F
Delbos
Jérome
J
Mégret
Sébastien
S
Storck
Claude-Agnès
CA
Reynaud
Jean-Claude
JC
Weill
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000201:enzymology / Q000276:immunology*; D002454:Cell Differentiation; D003564:Cytidine Deaminase; D018858:Germinal Center / Q000166:cytology / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007156:Immunologic Memory; D051379:Mice; D023421:Models, Animal; D009154:Mutation; D010641:Phenotype
D007074:Immunoglobulin G; D007075:Immunoglobulin M; D003564:Cytidine Deaminase