title: Anti-group B Streptococcus antibody in infants born to mothers with human immunodeficiency virus (HIV) infection.
abstract: BACKGROUND
  HIV-exposed uninfected infants have increased infection risk and mortality compared to HIV-unexposed infants. HIV-exposed infants may be at increased risk of invasive GBS disease due to reduced maternal antibody against GBS.
  
  
  METHODS
  We quantified antibodies that bind to the surface of whole Group B Streptococcus (GBS) of serotypes Ia, Ib, II, III and V using novel flow cytometry assays in South African HIV-infected and non-infected mothers and their uninfected infants. Antibody-mediated complement C3b/iC3b deposition onto GBS of these serotypes was also quantified by a novel flow cytometry assay.
  
  
  RESULTS
  Geometric mean concentration (GMC) of both surface-binding anti-GBS antibody and antibody-mediated complement deposition onto GBS were reduced in HIV-infected women (n=46) compared to HIV-uninfected women (n=58) for ST1a (surface-binding: 19.3 vs 29.3; p=0.003; complement deposition: 2.9 vs 5.3 SU/mL; p=0.003), STIb (24.9 vs 47.6; p=0.003; 2.6 vs 4.9 SU/mL; p=0.003), STII (19.8 vs 50.0; p=0.001; 3.1 vs 6.2 SU/mL; p=0.001), STIII (27.8 vs 60.1; p=0.001; 2.8 vs 5.3 SU/mL; p=0.001) and STV (121.9 vs 185.6 SU/mL; p<0.001) and in their infants for STIa (complement deposition 9.4 vs 27.0 SU/mL; p=0.02), STIb (13.4 vs 24.5 SU/mL; p=0.02), STII (14.6 vs 42.7 SU/mL; p=0.03), STIII (26.6 vs 62.7 SU/mL; p=0.03) and STV (90.4 vs 165.8 SU/mL; p=0.04). Median transplacental transfer of antibody from HIV-infected women to their infants was reduced compared to HIV-uninfected women for GBS serotypes II (0.42 [IQR 0.22-0.59] vs 1.0 SU/mL [0.42-1.66]; p<0.001), III (0.54 [0.31-1.03] vs 0.95 SU/mL [0.42-3.05], p=0.05) and V (0.51 [0.28-0.79] vs 0.75 SU/mL [0.26-2.9], p=0.04). The differences between infants remained significant at 16 weeks of age.
  
  
  CONCLUSIONS
  Maternal HIV infection was associated with lower anti-GBS surface binding antibody concentration and antibody-mediated C3b/iC3b deposition onto GBS bacteria of serotypes Ia, Ib, II, III and V. This may render these infants more susceptible to early and late onset GBS disease.
authors.affiliation: Wellcome Trust/Imperial Centre for Global Health Research/Department of Academic Paediatrics, Imperial College London, Norfolk Place, London W2 1NY, UK; Paediatric Infectious Diseases Research Group, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK. Electronic address: k.mehring-le-doare@imperial.ac.uk.
authors.forename: Kirsty
authors.initials: K
authors.lastname: Le Doare
authors.affiliation: Public Health England, Porton Down, Salisbury SP4 0JG, UK.
authors.forename: Lauren
authors.initials: L
authors.lastname: Allen
authors.affiliation: Wellcome Trust/Imperial Centre for Global Health Research/Department of Academic Paediatrics, Imperial College London, Norfolk Place, London W2 1NY, UK; Medical Research Council, Atlantic Road, Fajara, Gambia.
authors.forename: Beate
authors.initials: B
authors.lastname: Kampmann
authors.affiliation: Paediatric Infectious Diseases Research Group, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
authors.forename: Paul Trafford
authors.initials: PT
authors.lastname: Heath
authors.affiliation: Public Health England, Porton Down, Salisbury SP4 0JG, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Taylor
authors.affiliation: Desmond Tutu TB Center, Department of Pediatrics and Child Health, Stellenbosch University, Cape Town, South Africa.
authors.forename: Anneke C
authors.initials: AC
authors.lastname: Hesseling
authors.affiliation: Public Health England, Porton Down, Salisbury SP4 0JG, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Gorringe
authors.affiliation: Wellcome Trust/Imperial Centre for Global Health Research/Department of Academic Paediatrics, Imperial College London, Norfolk Place, London W2 1NY, UK; Paediatric Infectious Diseases Research Group, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK; Desmond Tutu TB Center, Department of Pediatrics and Child Health, Stellenbosch University, Cape Town, South Africa.
authors.forename: Christine Elizabeth
authors.initials: CE
authors.lastname: Jones
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D015331:Cohort Studies; D003165:Complement System Proteins / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D007112:Immunity, Maternally-Acquired; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology*; D013019:South Africa; D013292:Streptococcus agalactiae / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D003165:Complement System Proteins
keywords: Antibody; Group B Streptococcus; HIV; HIV-exposed-uninfected infants; Immunity