The zwitterionic type I Streptococcus pneumoniae polysaccharide does not induce memory B cell formation in humans.
In contrast to other pneumococcal serotypes, which are thought to be T-independent antigens, type 1 Streptococcus pneumoniae polysaccharide (Sp1) is a zwitterionic polysaccharide (ZPS). It has previously been shown to be processed and presented by antigen-presenting cells utilizing the MHC-II pathway, which leads to Sp1-induced T cell proliferation, a hallmark of thymus-dependent immune responses. We used peripheral blood mononuclear cells obtained from adults enrolled in a randomised clinical trial to investigate memory B cell responses following immunisation with the 23-valent pneumococcal plain polysaccharide vaccine. Administration of this serotype 1 containing vaccine resulted in the depletion of serotype 1 antigen-specific pre-existing memory B cells compared to baseline. This finding indicates that this ZPS is not processed by a classical TD mechanism within the MHC-II pathway.
Department of Paediatrics, University of Oxford, and the NIHR Oxford Biomedical Research Centre, Oxford, United Kingdom. johannes.truck@paediatrics.ox.ac.uk
Johannes
J
Trück
Rajeka
R
Lazarus
Elizabeth A
EA
Clutterbuck
Jaclyn
J
Bowman
Elizabeth
E
Kibwana
Elizabeth A L
EA
Bateman
Andrew J
AJ
Pollard
D000368:Aged; D000942:Antigens, Bacterial / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007156:Immunologic Memory; D008297:Male; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000276:immunology*; D022242:Pneumococcal Vaccines / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000276:immunology; D013296:Streptococcus pneumoniae / Q000276:immunology*; D014611:Vaccination
D000942:Antigens, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D011135:Polysaccharides, Bacterial