title: The early kinetics of circulating pneumococcal-specific memory B cells following pneumococcal conjugate and plain polysaccharide vaccines in the elderly.
abstract: In young children, polyvalent pneumococcal polysaccharide conjugate vaccines (PCVs) have been shown to offer advantage over plain polysaccharide vaccines (PPVs) in both immunogenicity and priming for memory responses. In the elderly, the potential benefit of conjugate vaccines is unclear. Here, we explore the early kinetics of serum antibody and circulating plasma and memory B cell responses to pneumococcal capsular polysaccharide (PPS) in older adults (n=37) immunised a PPV vaccine, Pneumovax or a PCV: Prevenar. All individuals had serum evidence of pre-existing serotype-specific immunity. Following immunisation, a day 7 rise in circulating PPS-specific plasma and memory antibody secreting cells (AbSCs) was detected in both vaccine groups and this was sustained to day 28 in some PCV recipients. There was no difference between vaccine groups in serum antibody responses or the kinetics of the early PBMC-derived B cell responses. Although our sample cohort was small, these data are different from profiles in younger individuals at early time points post-immunisation and suggest that pneumococcal conjugate vaccines may not quantitatively enhance the generation of memory responses in the elderly.
authors.affiliation: Department of Immunology, University College London Medical School, Royal Free Hospital Campus, London NW3 2PF, UK. h.baxendale@medch.ucl.ac.uk
authors.forename: Helen E
authors.initials: HE
authors.lastname: Baxendale
authors.forename: Sheila M
authors.initials: SM
authors.lastname: Keating
authors.forename: Marina
authors.initials: M
authors.lastname: Johnson
authors.forename: Jo
authors.initials: J
authors.lastname: Southern
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Miller
authors.forename: David
authors.initials: D
authors.lastname: Goldblatt
mesh_terms: D000367:Age Factors; D000368:Aged; D000907:Antibodies, Bacterial / Q000032:analysis; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000276:immunology*; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000032:analysis / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000032:analysis / Q000096:biosynthesis; D007136:Immunoglobulins / Q000032:analysis; D007156:Immunologic Memory; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000276:immunology; D022242:Pneumococcal Vaccines / Q000276:immunology / Q000627:therapeutic use*; D011135:Polysaccharides, Bacterial / Q000276:immunology; D012737:Sex Factors; D014611:Vaccination; D018074:Vaccines, Conjugate
chemical_list: D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins; D022242:Pneumococcal Vaccines; D011135:Polysaccharides, Bacterial; D018074:Vaccines, Conjugate