Antibodies against pneumococcal capsular polysaccharide in Malawian HIV-positive mothers and their HIV-exposed uninfected children

Infect Dis (Lond). 2016 Apr;48(4):317-321. doi: 10.3109/23744235.2015.1115895. Epub 2015 Nov 26.

Abstract

Background HIV-exposed uninfected children have a higher risk of infection and mortality compared to HIV-unexposed children and the reasons for this vulnerability are still under investigation.

Aim: This study aimed to evaluate the influence of maternal HIV parameters on the passive transfer of anti-pneumococcal capsular polysaccharide (PCP) IgG and to determine whether the concentrations of specific IgG might be related to the morbidity and mortality in HIV-exposed uninfected children. Methods One hundred and twenty-six Malawian HIV-infected pregnant women and their uninfected children were studied. Antiretroviral treatment-naive women started a nevirapine-based triple combination regimen from the third trimester of pregnancy until at least 6 months of exclusive breastfeeding. Mother/child pairs were followed until 2 years after delivery. Plasma anti-PCP IgG titers (in mothers at 26 weeks of gestation and in infants at 1 and 6 months) were determined by an enzyme-linked immunosorbent assay. None of these women and children had received any vaccination against pneumococcal polysaccharides. Results Maternal anti-PCP IgG concentration was independent from viral load (p = 0.848), CD4 count (p = 0.740) and WHO stage (p = 0.450). However, the child/mother ratio of anti-PCP IgG measured at 1 month among infants was significantly reduced in pairs whose mothers had HIV-RNA > 10 000 copies/ml (p = 0.043) and CD4 < 350 cells/μl (p = 0.090) before antiretroviral therapy (ART). No clear associations between anti-PCP IgG and respiratory-related deaths were found, but respiratory infection episodes were more frequent among children with lower anti-PCP IgG ratio (p = 0.046). Conclusion This study indicates that HIV pre-ART conditions in mothers may influence the rate of specific immunoglobulins transfer, increasing infants vulnerability to respiratory infections.

Keywords: HIV exposed infants; Malawi; anti-pneumococcal IgG; passive transfer.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Anti-HIV Agents / administration & dosage*
  • Anti-HIV Agents / therapeutic use
  • Bacterial Capsules / immunology*
  • Child, Preschool
  • Female
  • HIV Infections / drug therapy
  • HIV Infections / immunology
  • HIV Infections / prevention & control*
  • HIV Infections / transmission
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Infant
  • Infant, Newborn
  • Infectious Disease Transmission, Vertical / prevention & control*
  • Malawi
  • Male
  • Nevirapine / therapeutic use
  • Pneumococcal Infections / immunology
  • Polysaccharides, Bacterial / immunology*
  • Pregnancy
  • Pregnancy Complications, Infectious / drug therapy*
  • Pregnancy Complications, Infectious / virology*
  • Viral Load

Substances

  • Anti-HIV Agents
  • Immunoglobulin G
  • Polysaccharides, Bacterial
  • Nevirapine