Background. Plasmodium falciparum placental infection primes the fetal immune system and alters infant immunity. Mechanisms leading to these outcomes are not completely understood. We focused on V gamma 2V delta 2 cells, which are part of the immune response against many pathogens, including P. falciparum. These unconventional lymphocytes respond directly to small, nonpeptidic antigens, independent of major histocompatibility complex presentation. We wondered whether placental malaria, which may increase fetal exposure to P. falciparum metabolites, triggers a response by neonatal V gamma 2V delta 2 lymphocytes that can be a marker for the extent of fetal exposure to malarial antigens. Methods. Cord blood mononuclear cells were collected from 15 neonates born to mothers with P. falciparum infection during pregnancy (8 with placental malaria) and 25 unexposed neonates. V gamma 2V delta 2cell phenotype, repertoire, and proliferative responses were compared between newborns exposed and those unexposed to P. falciparum. Results. Placental malaria-exposed neonates had increased proportions of central memory V gamma 2V delta 2 cells in cord blood, with an altered V?2 chain repertoire ex vivo and after stimulation. Conclusion. Our results suggest that placental malaria affects the phenotype and repertoire of neonatal V gamma 2V delta 2 lymphocytes. Placental malaria may lower the capacity for subsequent V gamma 2V delta 2 cell responses and impair the natural resistance to infectious diseases or the response to pediatric vaccination.
Cord Blood V gamma 2V delta 2 T Cells Provide a Molecular Marker for the Influence of Pregnancy-Associated Malaria on Neonatal Immunity
Cappelli G;
2014
Abstract
Background. Plasmodium falciparum placental infection primes the fetal immune system and alters infant immunity. Mechanisms leading to these outcomes are not completely understood. We focused on V gamma 2V delta 2 cells, which are part of the immune response against many pathogens, including P. falciparum. These unconventional lymphocytes respond directly to small, nonpeptidic antigens, independent of major histocompatibility complex presentation. We wondered whether placental malaria, which may increase fetal exposure to P. falciparum metabolites, triggers a response by neonatal V gamma 2V delta 2 lymphocytes that can be a marker for the extent of fetal exposure to malarial antigens. Methods. Cord blood mononuclear cells were collected from 15 neonates born to mothers with P. falciparum infection during pregnancy (8 with placental malaria) and 25 unexposed neonates. V gamma 2V delta 2cell phenotype, repertoire, and proliferative responses were compared between newborns exposed and those unexposed to P. falciparum. Results. Placental malaria-exposed neonates had increased proportions of central memory V gamma 2V delta 2 cells in cord blood, with an altered V?2 chain repertoire ex vivo and after stimulation. Conclusion. Our results suggest that placental malaria affects the phenotype and repertoire of neonatal V gamma 2V delta 2 lymphocytes. Placental malaria may lower the capacity for subsequent V gamma 2V delta 2 cell responses and impair the natural resistance to infectious diseases or the response to pediatric vaccination.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
