title: Natural and vaccine-induced immunity to Neisseria meningitidis serogroup C in asplenic patients with β-thalassemia.
abstract: Natural and vaccine-induced immunity to meningococcus C (MenC) was evaluated in asplenic adolescents and adults with β-thalassemia. At baseline 19.3% of patients and 22.8% age-matched controls had positive (>2 μg/ml) naturally acquired Men C- specific IgG antibodies; patients had a lower probability of having protective SBA compared to controls (OR=21, p=0.012). MenC conjugate vaccine (MCC) induced protective IgG concentrations in 63% of patients and 90.1% of controls. SBA increased significantly post vaccination and there were no differences between patients and controls; however patients had significantly lower IgG concentrations post vaccination compared to controls (4.52 vs 10.94 μg/ml, p<0.001, respectively). A second dose of MCC given to 11 patients who had received MCC in the past induced higher IgG compared to primary response (p=0.001). Naturally- and vaccine-induced immunity to MenC is impaired in asplenic β-thalassemics; a second dose of MCC improves vaccine immunogenicity and is essential for their optimal protection.
authors.affiliation: 1st Department of Paediatrics, Division of Infectious Diseases, Athens University School of Medicine, Greece. vspoulou@med.uoa.gr
authors.forename: Vana
authors.initials: V
authors.lastname: Spoulou
authors.forename: Georgina
authors.initials: G
authors.lastname: Tzanakaki
authors.forename: Sophia
authors.initials: S
authors.lastname: Lekka
authors.forename: Giorgos
authors.initials: G
authors.lastname: Chouliaras
authors.forename: Vassilis
authors.initials: V
authors.lastname: Ladis
authors.forename: Maria
authors.initials: M
authors.lastname: Theodoridou
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000918:Antibody Specificity; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007114:Immunization; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008297:Male; D008589:Meningococcal Infections / Q000276:immunology* / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D038542:Neisseria meningitidis, Serogroup C / Q000276:immunology*; D013156:Splenectomy; D016896:Treatment Outcome; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology*; D055815:Young Adult; D017086:beta-Thalassemia / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022401:Meningococcal Vaccines; D018074:Vaccines, Conjugate