In utero sensitization in Chagas' disease leads to altered lymphocyte phenotypic patterns in the newborn cord blood mononuclear cells.
Neonates are sensitized in utero to maternal circulating antigens and idiotypes that eventually cross the placental barrier. We believe that children born of mothers under long lasting antigenic stimulation, as in a chronic infection, would be affected by these maternal influences and show differences in the phenotypic repertoire of lymphocytes. To test this hypothesis, we evaluated flow cytometry studies in cord blood mononuclear cells (CBMC) from children born of chagasic mothers without congenital disease, with special attention to T and B cells and expression of activation markers. We have also evaluated the peripheral blood mononuclear cells (PBMC) of these children 6 months after delivery. We show that CBMC of children born of infected mothers have high proliferative responses to antigenic stimulation, significantly lower mean percentages of CD3+ T cells, CD4+ T cells and diminished expression of the costimulatory molecule CD28 in the CD8+ T cell subset. Interestingly, this subpopulation has an increased expression of the MHC class II gene product as evidenced by the expression of HLADR. It is noteworthy that the patterns observed in CBMC T lymphocyte populations of these children closely resemble earlier findings on lymphocytic profiles of chronic chagasic adult patients and those of their mothers. We also show that, 6 months after delivery, some alterations observed at birth are reversed to levels observed in noninfected individuals.
Neves
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SF
Laboratorio de Immunologia Celular e Molecular de Parasitas, Centro de Pesquisas Rene Rachou/FIOCRUZ Avenida Augusto de Lima 1715, Barro Preto-CEP 30190-002, Belo Horizonte, MG.
Elói-Santos
S
S
Ramos
R
R
Rigueirinho
S
S
Gazzinelli
G
G
Correa-Oliveira
R
R
D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D014355:Chagas Disease / Q000276:immunology*; D005260:Female; D005312:Fetal Blood / Q000276:immunology; D005434:Flow Cytometry; D006681:HLA-D Antigens / Q000032:analysis; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D007231:Infant, Newborn; D007963:Leukocytes, Mononuclear / Q000276:immunology; D018655:Lymphocyte Count; D018811:Maternal Exposure; D011817:Rabbits; D016176:T-Lymphocyte Subsets / Q000276:immunology
D015703:Antigens, CD; D006681:HLA-D Antigens