Serum antibody response to five Streptococcus pneumoniae proteins during acute otitis media in otitis-prone and non-otitis-prone children

Pediatr Infect Dis J. 2011 Aug;30(8):645-50. doi: 10.1097/INF.0b013e31821c2d8b.


Background: Streptococcus pneumoniae (Spn) is one of the common bacteria responsible for episodic acute otitis media (AOM; non-otitis-prone), recurrent AOM (otitis-prone), and AOM treatment failure (AOMTF) in children.

Objective: From a population of 268 children, we sought to compare the serum IgG antibody titers of 5 different Spn proteins (PhtD, LytB, PcpA, PhtE, and Ply) that are vaccine candidates in children with episodic AOM (n = 34), who were otitis prone (n = 35) and who had AOMTF (n = 25) caused by Spn.

Methods: Antibody was quantitated by enzyme-linked immunosorbent assay.

Results: At their AOM visit, anti-PhtD, -LytB, -PhtE, and -Ply IgG antibody titers in otitis-prone children were significantly lower compared with non-otitis-prone children (P < 0.05) and children with AOMTF (P < 0.05). On comparing acute to convalescent geometric mean IgG antibody titers after AOM against the 5 proteins we found that otitis-prone, AOMTF, and non-otitis-prone children had no significant change in titers (except for PhtE in children with AOMTF), but detailed analysis showed that about one-third of the children in each cohort had a 2-fold rise in antibody to the studied antigens. Although non-otitis-prone children had significant increases (P < 0.001) between 6 and 24 months of age in anti-PhtD, PcpA, PhtE, and Ply IgG antibody titers as a consequence of nasopharyngeal colonization and AOM, otitis-prone children either failed to show rises or the rises were significantly less than the non-otitis-prone children.

Conclusion: Otitis-prone and AOMTF children mount less of an IgG serum antibody response as compared with non-otitis-prone children to Spn proteins after AOM and nasopharyngeal colonization.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Bacterial / blood*
  • Antigens, Bacterial / immunology*
  • Bacterial Proteins / immunology
  • Child, Preschool
  • Disease Susceptibility / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / blood
  • Infant
  • Otitis Media / immunology*
  • Otitis Media / microbiology
  • Pneumococcal Infections / immunology*
  • Pneumococcal Infections / microbiology
  • Prospective Studies
  • Serum / immunology
  • Streptococcus pneumoniae / immunology*


  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Bacterial Proteins
  • Immunoglobulin G