title: Serotype-specific pneumococcal antibodies in breast milk of Gambian women immunized with a pneumococcal polysaccharide vaccine during pregnancy.
abstract: BACKGROUND
  In breast-feeding populations, immunization during pregnancy with pneumococcal polysaccharide offers a potentially useful approach to preventing pneumococcal disease in young infants.
  
  
  METHODS
  Breast milk samples were collected at 0, 2, 4 and 6 months after delivery from Gambian women vaccinated during pregnancy (24-32 weeks gestation) with Pneumovax II (n = 56) or Mengivax A&C (n = 57). Specimens were examined for secretory immunoglobulin A (s-IgA) concentration, subclass distribution and avidity specific to pneumococcal serotypes 4, 6B, 14, 19F and 23F and the antigen mixture in Pneumovax II by enzyme-linked immunosorbent assay. Colostral s-IgA and IgG concentrations in paired maternal sera were compared.
  
  
  RESULTS
  Colostral s-IgA concentrations specific to all pneumococcal polysaccharide antigens investigated were significantly higher (P < 0.05) among Pneumovax II vaccinees. Titers specific to serotypes 4, 6B and 14 and the vaccine formula remained significantly higher during 6 months, and those for 19F were higher during 4 months. Significantly higher concentrations of vaccine antigen-specific s-IgA antibody were sustained for 6 months after delivery (P = 0.011). Comparison of colostral s-IgA and IgG in serum revealed a significant correlation only among Mengivax A&C vaccinees for pneumococcal polysaccharide 23F (rs= 0.68; P < or = 0.0001). Vaccination elicited trends toward increased s-IgA2, reaching significance for serotype 14 and the vaccine formula. Immunization elicited significantly higher s-IgA avidities specific to all pneumococcal polysaccharide antigens studied during 6 months.
  
  
  CONCLUSIONS
  The public health value of immunization during pregnancy with pneumococcal polysaccharide vaccine in breast-feeding populations warrants further evaluation, particularly in populations with a high incidence of pneumococcal disease in early infancy.
authors.affiliation: Imperial College, School of Science, Technology and Medicine, Department of Immunology, Chelsea and Westminster Hospital, London, United Kingdom.
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Obaro
authors.forename: Hedwig E
authors.initials: HE
authors.lastname: Deubzer
authors.forename: Vanessa O
authors.initials: VO
authors.lastname: Newman
authors.forename: Richard A
authors.initials: RA
authors.lastname: Adegbola
authors.forename: Brian M
authors.initials: BM
authors.lastname: Greenwood
authors.forename: Don C
authors.initials: DC
authors.lastname: Henderson
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000032:analysis*; D003906:Developing Countries; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005714:Gambia / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008895:Milk, Human / Q000276:immunology*; D011008:Pneumococcal Infections / Q000151:congenital / Q000453:epidemiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000517:prevention & control*; D011256:Pregnancy Outcome; D011336:Probability; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D014611:Vaccination / Q000379:methods
chemical_list: D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines