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Myszczynski, K.

Publications and source records attributed to Myszczynski, K..

2 recordsLinked to original sources

Embryonic signals mediate extracellular vesicle biogenesis and trafficking at the embryo-maternal interface

Extracellular vesicles (EVs) are membrane-coated nanoparticles secreted by almost all cell types in living organisms. EVs, as paracrine mediators, are involved in intercellular communication, immune response, and several reproductive events, including the maintenance of pregnancy. Using a domestic animal model (Sus scrofa) with an epitheliochorial, superficial type of placentation, we focused on EV biogenesis pathway at the embryo-maternal interface, when the embryonic signaling occurs for maternal recognition and the maintenance of pregnancy. Transmission electron microscopy was used during early pregnancy to visualize different populations of EVs and apocrine and/or merocrine pathways of secretion. Immunofluorescent staining localized proteins responsible for EV biogenesis and cell polarization at the embryo-maternal interface. The expression profiles of genes involved in biogenesis and the secretion of EVs pointed at the possible modulation of endometrial expression by embryonic signals. Further in vitro studies showed that factors of embryonic origin can regulate the expression of the ESCRT-II complex and EV trafficking in luminal epithelial cells. Moreover, miRNA-mediated rapid negative regulation of gene expression was abolished by delivered embryonic signals. Our findings demonstrated that embryonic signals are potent modulators of EV-mediated secretory activity of the endometrium during the critical stages of early pregnancy.

physiology↗

Early steps of embryo implantation are regulated by exchange of extracellular vesicles between the embryo and the endometrium

In early pregnancy, as the embryo arrives in the uterus, intensive communication between the embryo and uterus begins. Hundreds of molecules are known to be involved, but despite numerous findings, full understanding of the complexity of the embryo-maternal dialog remains elusive. Recently, extracellular vesicles, nanoparticles able to transfer functionally active cargo between cells, have emerged as important players in cell-cell communication, and as such, they have gained great attention over the past decade also in reproductive biology. Here we use a domestic animal model (Sus scrofa) with an epitheliochorial, superficial type of placentation because of its advantage in studding uterine luminal fluid extracellular vesicles. We show that during early pregnancy, the uterine lumen is abundant with extracellular vesicles that carry a plethora of miRNAs able to target genes involved in embryonic and organismal development. These extracellular vesicles, upon the delivery to primary trophoblast cells, affect genes governing development as well as cell-to-cell signaling and interactions, consequently having an impact on trophoblast cell proliferation, migration, and invasion. We conclude that exchange of a unique population of extracellular vesicles and their molecular cargo at the maternal-embryo interface is the key to the success of embryo implantation and pregnancy.

physiology↗