title: In vitro triggering of somatic mutation in human naive B cells.
abstract: During T cell-dependent immune response, germinal center B cells accumulate somatic mutations in their Ig V(D)J genes and give rise to affinity-selected B cells. We tested several culture conditions for triggering somatic mutation in human tonsillar naive slgD+CD23+ cells after cross-linking their membrane Igs. CD40 activation, in the presence of exogenous cytokines (IL-2, IL-4, and IL-10), induced proliferation and isotype switch without somatic mutation. In contrast, after coculture with anti-CD3-activated cloned T cells, somatic mutation accumulated in a fraction of naive B cells. Mutations included shared as well as independent events in clonally related sequences, allowing reconstitution of genealogic trees generated in vitro. Naive tonsillar B cells sorted for slgD expression can be induced to mutate their Ig V(H) gene upon coculture with activated T cells, thereby providing a model to study somatic hypermutation in vitro.
authors.affiliation: Laboratory for Immunological Research, Schering-Plough, Dardilly, France.
authors.forename: D
authors.initials: D
authors.lastname: Razanajaona
authors.forename: S
authors.initials: S
authors.lastname: Denépoux
authors.forename: D
authors.initials: D
authors.lastname: Blanchard
authors.forename: O
authors.initials: O
authors.lastname: de Bouteiller
authors.forename: Y J
authors.initials: YJ
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Banchereau
authors.forename: S
authors.initials: S
authors.lastname: Lebecque
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D017252:CD3 Complex / Q000276:immunology; D018929:Cell Culture Techniques / Q000379:methods; D002999:Clone Cells; D018920:Coculture Techniques; D005803:Genes, Immunoglobulin; D006801:Humans; D007072:Immunoglobulin D / Q000096:biosynthesis; D007132:Immunoglobulin Isotypes / Q000235:genetics / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics; D007399:Interphase / Q000276:immunology; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D009154:Mutation / Q000276:immunology*; D014066:Palatine Tonsil / Q000166:cytology; D011947:Receptors, Antigen, B-Cell / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D007072:Immunoglobulin D; D007132:Immunoglobulin Isotypes; D007135:Immunoglobulin Variable Region; D011947:Receptors, Antigen, B-Cell