Memory B-cell clones and the diversity of their members.
Memory B-cell clones develop from virgin B cells that take up processed antigen, make cognate interaction with primed T cells and then grow in germinal centres. Within the germinal centre the proliferating B cells undergo Ig variable-region mutation and are subsequently selected on their ability to bind antigen held on follicular dendritic cells and then to make cognate interaction with germinal centre T cells. The selected cells emerge as memory B cells or plasmablasts. Although many of the memory B cells and most of the plasma cells emerging from follicles have undergone Ig class switch recombination a substantial minority of the memory B cells have not switched. These non-switched memory cells can be induced to switch on re-exposure to antigen. Affinity maturation following a single immunization ceases as germinal centres wane some 3-4 weeks after immunization - memory cells and antibody production, on the other hand, persist for months and even years.
MacLennan
I C
IC
Department of Immunology, University of Birmingham Medical School, Birmingham, B15 2TT, U.K.
Casamayor-Palleja
M
M
Toellner
K M
KM
Gulbranson-Judge
A
A
Gordon
J
J
D000818:Animals; D017951:Antigen Presentation; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D016922:Cellular Senescence; D002999:Clone Cells / Q000166:cytology / Q000276:immunology; D018858:Germinal Center / Q000166:cytology / Q000276:immunology; D006801:Humans; D007134:Immunoglobulin Switch Region; D007156:Immunologic Memory; D008211:Lymphocyte Cooperation; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology