Microbial exposure during early human development primes fetal immune cells.
Cell
; 184(13): 3394-3409.e20, 2021 06 24.
Article
em En
| MEDLINE
| ID: mdl-34077752
ABSTRACT
The human fetal immune system begins to develop early during gestation; however, factors responsible for fetal immune-priming remain elusive. We explored potential exposure to microbial agents in utero and their contribution toward activation of memory T cells in fetal tissues. We profiled microbes across fetal organs using 16S rRNA gene sequencing and detected low but consistent microbial signal in fetal gut, skin, placenta, and lungs in the 2nd trimester of gestation. We identified several live bacterial strains including Staphylococcus and Lactobacillus in fetal tissues, which induced in vitro activation of memory T cells in fetal mesenteric lymph node, supporting the role of microbial exposure in fetal immune-priming. Finally, using SEM and RNA-ISH, we visualized discrete localization of bacteria-like structures and eubacterial-RNA within 14th weeks fetal gut lumen. These findings indicate selective presence of live microbes in fetal organs during the 2nd trimester of gestation and have broader implications toward the establishment of immune competency and priming before birth.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bactérias
/
Desenvolvimento Embrionário
/
Feto
/
Leucócitos
Tipo de estudo:
Prognostic_studies
Limite:
Adult
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Female
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Humans
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Pregnancy
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article