title: Long-lived memory B-cell responses following BCG vaccination.
abstract: The role of T-cells in immunity against Mycobacterium tuberculosis (M. tuberculosis) infection has been extensively studied, however, that of B-cells still remains comparatively unexplored. In this study, we determined the presence and frequencies of mycobacteria-specific memory B-cells (MBCs) in peripheral blood from clinically healthy, Bacillus Calmette Guerin (BCG) vaccinated (n = 79) and unvaccinated (n = 14) donors. Purified protein derivative (PPD)-specific MBCs were present in most donors (both vaccinated and unvaccinated) but their frequencies were significantly higher in vaccinated than in unvaccinated donors. MBCs specific for other mycobacterial antigens [antigen-85A (Ag85A), antigen-85B (Ag85B), 6 kDalton early secretory antigenic target (ESAT-6) and the 10 kDalton-culture filtrate protein (CFP-10)] were less prevalent than those recognising PPD. Furthermore, PPD-specific MBCs were detected in BCG vaccinated donors without ESAT-6 and CFP-10 specific responses. Together, these results indicate that BCG vaccination induces long-lived MBC responses. Similar patterns of response were seen when we examined mycobacteria-specific antibody and T-cell responses in these donors. Our data show for the first time that BCG vaccination elicits long-lived mycobacteria-specific MBC responses in healthy individuals, suggesting a more substantial role of B-cells in the response to BCG and other mycobacterial infections than previously thought.
authors.affiliation: Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom. ismail.sebina@mrcuganda.org
authors.forename: Ismail
authors.initials: I
authors.lastname: Sebina
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Cliff
authors.forename: Steven G
authors.initials: SG
authors.lastname: Smith
authors.forename: Sarah
authors.initials: S
authors.lastname: Nogaro
authors.forename: Emily L
authors.initials: EL
authors.lastname: Webb
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Riley
authors.forename: Hazel M
authors.initials: HM
authors.lastname: Dockrell
authors.forename: Alison M
authors.initials: AM
authors.lastname: Elliott
authors.forename: Julius C R
authors.initials: JC
authors.lastname: Hafalla
authors.forename: Stephen
authors.initials: S
authors.lastname: Cose
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001500:BCG Vaccine / Q000008:administration & dosage; D006801:Humans; D007156:Immunologic Memory; D008213:Lymphocyte Activation / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000276:immunology / Q000472:pathogenicity; D013601:T-Lymphocytes / Q000276:immunology; D014376:Tuberculosis / Q000276:immunology / Q000382:microbiology; D014611:Vaccination
chemical_list: D000942:Antigens, Bacterial; D001500:BCG Vaccine