title: Maternal infection with Trypanosoma cruzi and congenital Chagas disease induce a trend to a type 1 polarization of infant immune responses to vaccines.
abstract: BACKGROUND
  We previously showed that newborns congenitally infected with Trypanosoma cruzi (M+B+) display a strong type 1 parasite-specific T cell immune response, whereas uninfected newborns from T. cruzi-infected mothers (M+B-) are prone to produce higher levels of proinflammatory cytokines than control neonates (M-B-). The purpose of the present study was to determine if such fetal/neonatal immunological environments could alter the response to standard vaccines administered in early life.
  
  
  METHODS
  Infants (6-7 months old) living in Bolivia, an area highly endemic for T. cruzi infection, and having received Bacillus Calmette Guerin (BCG), hepatitis B virus (HBV), diphtheria and tetanus vaccines, were enrolled into the M+B+, M+B-, M-B- groups mentioned above. The production of IFN-gamma and IL-13, as markers of Th1 and Th2 responses respectively, by peripherical blood mononuclear cells stimulated with tuberculin purified protein derivative of Mycobacterium tuberculosis (PPD) or the vaccinal antigens HBs, diphtheria toxoid (DT) or tetanus toxoid (TT), as well as circulating levels of IgG antibodies against HBsAg, DT and TT were analyzed in infants. Cellular responses to the superantigen SEB were also monitored in M+B+, M+B-, M-B-infants and newborns.
  
  
  RESULTS
  M+B+ infants developed a stronger IFN-gamma response to hepatitis B, diphtheria and tetanus vaccines than did M+B- and M-B- groups. They also displayed an enhanced antibody production to HBsAg. This was associated with a type 1-biased immune environment at birth, since cells of M+B+ newborns produced higher IFN-gamma levels in response to SEB. M+B- infants produced more IFN-gamma in response to PPD than the other groups. IL-13 production remained low and similar in all the three groups, whatever the subject's ages or vaccine status.
  
  
  CONCLUSIONS
  These results show that: i) both maternal infection with T. cruzi and congenital Chagas disease do not interfere with responses to BCG, hepatitis B, diphtheria and tetanus vaccines in the neonatal period, and ii) the overcoming of immunological immaturity by T. cruzi infection in early life is not limited to the development of parasite-specific immune responses, but also tends to favour type 1 immune responses to vaccinal antigens.
authors.affiliation: Laboratoire de Parasitologie, Faculté de Médecine, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Dauby
authors.forename: Cristina
authors.initials: C
authors.lastname: Alonso-Vega
authors.forename: Eduardo
authors.initials: E
authors.lastname: Suarez
authors.forename: Amilcar
authors.initials: A
authors.lastname: Flores
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Hermann
authors.forename: Marisol
authors.initials: M
authors.lastname: Córdova
authors.forename: Tatiana
authors.initials: T
authors.lastname: Tellez
authors.forename: Faustino
authors.initials: F
authors.lastname: Torrico
authors.forename: Carine
authors.initials: C
authors.lastname: Truyens
authors.forename: Yves
authors.initials: Y
authors.lastname: Carlier
mesh_terms: D000328:Adult; D014355:Chagas Disease / Q000151:congenital / Q000276:immunology* / Q000469:parasitology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn / Q000276:immunology*; D008297:Male; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000276:immunology / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000276:immunology / Q000502:physiology*; D014611:Vaccination; D014612:Vaccines / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D014612:Vaccines