Defining subsets of naive and memory B cells based on the ability of their progeny to somatically mutate in vitro.
The increased affinity of memory antibody responses is due largely to the generation and selection of memory B cells that accumulate somatic mutations after initial antigenic stimulation. Further affinity maturation and mutation also accompany subsequent immunizations. Previous studies have suggested that, like primary antibody-forming cell (AFC) clones, secondary AFC do not accumulate further mutations and, therefore, the origins of progressive affinity maturation remain controversial. Here, we report the generation of somatically mutated memory B cell clones in vitro. Our findings confirm the existence of a naive B cell subset whose progeny, rather than generating AFC, somatically mutate and respond to subsequent antigenic stimulation. Interestingly, upon stimulation, a subset of memory B cells also generates antigen-responsive cells that accumulate further somatic mutations.
Decker
D J
DJ
Department of Immunology, Scripps Research Institute, La Jolla, California 92037.
Linton
P J
PJ
Zaharevitz
S
S
Biery
M
M
Gingeras
T R
TR
Klinman
N R
NR
D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D001483:Base Sequence; D002478:Cells, Cultured; D007156:Immunologic Memory / Q000235:genetics / Q000276:immunology*; D016131:Lymphocyte Subsets; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D012313:RNA / Q000032:analysis; D013234:Stem Cells / Q000276:immunology
D012313:RNA