Maternal antibodies to pneumolysin but not to pneumococcal surface protein A delay early pneumococcal carriage in high-risk Papua New Guinean infants

Clin Vaccine Immunol. 2009 Nov;16(11):1633-8. doi: 10.1128/CVI.00247-09. Epub 2009 Sep 23.

Abstract

Immunization of pregnant women can be an efficient strategy to induce early protection in infants in developing countries. Pneumococcal protein-based vaccines may have the capacity to induce pneumococcal serotype-independent protection. To understand the potential of maternal pneumococcal protein-specific antibodies in infants in high-risk areas, we studied the placental transfer of naturally acquired antibodies to pneumolysin (Ply) and pneumococcal surface protein A family 1 and 2 (PspA1 and PspA2) in relation to onset of pneumococcal nasopharyngeal carriage in infants in Papua New Guinea (PNG). In this study, 76% of the infants carried Streptococcus pneumoniae in the upper respiratory tract within the first month of life, at a median age of 19 days. Maternal and cord blood antibody titers to Ply (rho = 0.824, P < 0.001), PspA1 (rho = 0.746, P < 0.001), and PspA2 (rho = 0.631, P < 0.001) were strongly correlated. Maternal pneumococcal carriage (hazard ratio [HR], 2.60; 95% confidence interval [CI], 1.25 to 5.39) and younger maternal age (HR, 0.74; 95% CI, 0.54 to 1.00) were independent risk factors for early carriage, while higher cord Ply-specific antibody titers predicted a significantly delayed onset (HR, 0.71; 95% CI, 0.52 to 1.00) and cord PspA1-specific antibodies a significantly younger onset of carriage in PNG infants (HR, 1.57; 95% CI, 1.03 to 2.40). Maternal vaccination with a pneumococcal protein-based vaccine should be considered as a strategy to protect high-risk infants against pneumococcal disease by reducing carriage risks in both mothers and infants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antibodies, Bacterial / blood*
  • Bacterial Proteins / immunology*
  • Carrier State / epidemiology
  • Carrier State / immunology
  • Carrier State / prevention & control*
  • Female
  • Humans
  • Immunity, Maternally-Acquired*
  • Infant, Newborn
  • Nasopharynx / microbiology
  • Papua New Guinea / epidemiology
  • Pneumococcal Infections / epidemiology
  • Pneumococcal Infections / immunology
  • Pneumococcal Infections / prevention & control*
  • Pregnancy
  • Prevalence
  • Streptococcus pneumoniae / immunology*
  • Streptococcus pneumoniae / isolation & purification
  • Streptolysins / immunology*
  • Young Adult

Substances

  • Antibodies, Bacterial
  • Bacterial Proteins
  • Streptolysins
  • plY protein, Streptococcus pneumoniae
  • pneumococcal surface protein A