title: Response to polysaccharide antigens in patients with ataxia-telangiectasia.
abstract: OBJECTIVE
  To analyze the production of antibodies to polysaccharide antigens in patients with ataxia-telangiectasia.
  
  
  METHODS
  We used the ELISA technique to measure the levels of IgG antibodies to serotypes 1, 3, 5, 6B, 9V and 14 of Streptococcus pneumoniae in 14 patients with ataxia-telangiectasia before and after immunization with 23-valent polysaccharide vaccine. Adequate response to individual polysaccharide can be defined as a postimmunization antibody titer equal to or greater than 1.3 microg/ml or as a minimum fourfold increase over the baseline (preimmunization) value.
  
  
  RESULTS
  Six (43%) patients showed an absent response to all serotypes analyzed. Four patients showed adequate response to only one serotype, one patient to two serotypes, two patients to three serotypes and only one patient to four out of six serotypes analyzed. No patient had adequate response to all serotypes tested. Postimmunization pneumococcus IgG levels were higher than preimmunization levels to all serotypes analyzed, except for serotype 3. In spite of this, the mean postimmunization levels were lower than 1.3 microg/ml in all serotypes, except for serotype 14. Mean increment was less than four in all serotypes analyzed.
  
  
  CONCLUSIONS
  Our results suggest that patients with ataxia-telangiectasia are at a high risk of having an impaired response to pneumococcus, which may be one of the causes of recurrent sinopulmonary infections in these patients.
authors.affiliation: Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Guerra-Maranhão
authors.forename: Beatriz T
authors.initials: BT
authors.lastname: Costa-Carvalho
authors.forename: Victor
authors.initials: V
authors.lastname: Nudelman
authors.forename: Patrícia
authors.initials: P
authors.lastname: Barros-Nunes
authors.forename: Magda M S
authors.initials: MM
authors.lastname: Carneiro-Sampaio
authors.forename: Cristina
authors.initials: C
authors.lastname: Arslanian
authors.forename: Aparecida T
authors.initials: AT
authors.lastname: Nagao-Dias
authors.forename: Dirceu
authors.initials: D
authors.lastname: Solé
mesh_terms: D000293:Adolescent; D000907:Antibodies, Bacterial / Q000097:blood*; D001260:Ataxia Telangiectasia / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D011008:Pneumococcal Infections / Q000276:immunology; D022242:Pneumococcal Vaccines / Q000276:immunology*; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D014611:Vaccination
chemical_list: C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D011135:Polysaccharides, Bacterial