title: Clonal dissection of the human memory B-cell repertoire following infection and vaccination.
abstract: The analysis of the human memory B-cell repertoire is of both fundamental and practical significance. We developed a simple method for the selective activation of memory B cells in total fresh or frozen PBMC using a combination of R848 and IL-2. In these conditions, 30-40% of memory B cells generated clones producing on average 200 ng IgG in 10 days. This method was used to measure the frequency of antigen-specific memory B cells as well as the fine specificity, cross-reactivity and neutralizing activity of the secreted antibodies. Following influenza vaccination, specific B cells expanded dramatically, reaching up to 50% of total clonable memory B cells on day 14. Specific B-cell expansions were detected also in individuals that did not show a significant serological response. Dynamic changes and persistence of B cells specific for a variety of pathogens were documented in serial PBMC samples collected over almost two decades. These results reveal novel aspects of memory B-cell kinetics and provide a powerful tool to monitor immune responses following infection and vaccination.
authors.affiliation: Institute for Research in Biomedicine, Bellinzona, Switzerland.
authors.forename: Debora
authors.initials: D
authors.lastname: Pinna
authors.forename: Davide
authors.initials: D
authors.lastname: Corti
authors.forename: David
authors.initials: D
authors.lastname: Jarrossay
authors.forename: Federica
authors.initials: F
authors.lastname: Sallusto
authors.forename: Antonio
authors.initials: A
authors.lastname: Lanzavecchia
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation / Q000187:drug effects / Q000276:immunology; D002999:Clone Cells / Q000276:immunology; D016207:Cytokines / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D018985:Epitopes, B-Lymphocyte / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007156:Immunologic Memory / Q000276:immunology*; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000097:blood / Q000276:immunology* / Q000821:virology; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000276:immunology; D051193:Toll-Like Receptors / Q000819:agonists / Q000276:immunology
chemical_list: D016207:Cytokines; D018985:Epitopes, B-Lymphocyte; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D051193:Toll-Like Receptors