Maternal platelets pass interstices of trophoblast columns and are not activated by HLA-G in early human pregnancy.
J Reprod Immunol
; 144: 103280, 2021 04.
Article
em En
| MEDLINE
| ID: mdl-33530024
ABSTRACT
In early human gestation, maternal arterial blood flow into the intervillous space of the developing placenta is obstructed by invaded trophoblasts, which form cellular plugs in uterine spiral arteries. These trophoblast plugs have recently been described to be loosely cohesive with clear capillary-sized channels into the intervillous space by 7 weeks of gestation. Here, we analysed localisation of maternal platelets at the maternal-foetal interface of human first trimester pregnancy, and tested the hypothesis whether HLA-G, which is primarily expressed by extravillous trophoblasts, affects aggregation and adhesion of isolated platelets. Immunohistochemistry of first trimester placental sections localised maternal platelets in vessel-like channels and adjacent intercellular gaps of extravillous trophoblasts in distal parts of columns. Furthermore, this localisation was confirmed by transmission electron microscopy. Neither co-incubation of HLA-G overexpressing JAR cells with isolated platelets, nor incubation with cell-derived soluble HLA-G or recombinant HLA-G affected platelet adhesion and aggregation. Our study suggests that maternal platelets flow through vessel-like channels of distal trophoblast columns and spread into adjacent lateral intercellular gaps, where platelet-derived factors could contribute to trophoblast differentiation into the invasive phenotype.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Trofoblastos
/
Plaquetas
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Diferenciação Celular
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Circulação Placentária
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Troca Materno-Fetal
Limite:
Female
/
Humans
/
Pregnancy
Idioma:
En
Revista:
J Reprod Immunol
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Áustria