title: The effect of 23-valent pneumococcal polysaccharide vaccine on immunological priming induced by 7-valent conjugate vaccine in asplenic subjects with beta-thalassemia.
abstract: The effect of the 23-valent pneumococcal polysaccharide vaccine (PPV) on the 7-valent conjugate (PCV) vaccine-induced priming was evaluated in 35 splenectomised beta-thalassemics [median (range) age: 30 (12-41) years] vaccinated with either PCV/PPV or two PCVs 1 month apart, followed by a PPV booster 12 months later. 28/35 had already received 1-3 PPVs in the past. Different schedules induced similar anamnestic responses; however priming for 3/5 serotypes induced by one or two PCVs, was inferior in subjects who had received > or =2 PPVs in the past when compared with 23 aged-matched PPV-naïve beta-thalassemics. One PPV following PCV does not affect PCV priming; multiple PPVs induce hyporesponsiveness for some serotypes in splenectomised subjects with beta-thalassemia.
authors.affiliation: 1st Department of Pediatrics, Division of Infectious Diseases, Aghia Sophia Children's Hospital, Athens University School of Medicine, Thivon and M. Asias St., Goudi, 11527 Athens, Greece.
authors.forename: George V
authors.initials: GV
authors.lastname: Orthopoulos
authors.forename: Maria C
authors.initials: MC
authors.lastname: Theodoridou
authors.forename: Vasilis A
authors.initials: VA
authors.lastname: Ladis
authors.forename: Dimitris K
authors.initials: DK
authors.lastname: Tsousis
authors.forename: Vana I
authors.initials: VI
authors.lastname: Spoulou
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007117:Immunization, Secondary; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D022242:Pneumococcal Vaccines / Q000276:immunology*; D013156:Splenectomy; D055815:Young Adult; D017086:beta-Thalassemia
chemical_list: C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines