Human Placental Trophoblasts Are Resistant to Trypanosoma cruzi Infection in a 3D-Culture Model of the Maternal-Fetal Interface

Abstract

Trypanosoma cruzi (T. cruzi), the etiological agent of Chagas Disease (CD), is transmitted to humans by infected kissing bugs, blood transfusion, organ transplantation, and from mother-to-child. Congenital transmission is now considered an important route of CD spread in non-endemic countries where no routine testing of pregnant women for the disease is implemented. The main cellular mechanisms that lead to fetal infection by T. cruzi, despite the presence of a placental barrier, remain unclear. Mother-to-child transmission most likely occurs when bloodstream trypomastigotes reach the placental intervillous space and interact with the large cellular surface provided by the syncytioptrophoblasts. These highly specialized cells not only function as a physical obstacle between mother and fetus, but also modulate immune responses against pathogen infections. To overcome the limitations associated with the use of human fetal tissues, we employed a three-dimensional (3D) cell culture model to recreate the human placenta environment. In this system, the trophoblast-derived JEG-3 cell line is co-cultured with human brain microvascular endothelial cells attached to microcarrier beads in a rotating bioreactor. Here, we report that 3D culture of JEG-3/HBMEC spheroids promote JEG-3 cells differentiation revealed by the formation of syncytia and production of β human chorionic gonadotropin and human placental lactogen (hPL). Under these growth conditions, we demonstrate that 3D-grown JEG-3 cells have reduced susceptibility to T. cruzi infection compared to JEG-3 cells grown in conventional tissue culture flasks. We also show that 3D-cultured JEG-3 cells release paracrine factors in the supernatant that prevent T. cruzi infection of non-trophoblastic cell lines. Our in vitro model of T. cruzi vertical transmission may help better understand the molecular processes by which parasites bypass the human placental barrier and could be exploited to evaluate therapeutics to reduce congenital CD.

A comprehensive review of human trophoblast fusion models: recent developments and challenges

“…The 3D trophoblast fusion models provide a better simulation of 3D structure and multicellular complexity of tissue, meanwhile serving as a platform for studying drug and nutrient transport, pathogen infection, and STBEVs release [ 118 , 119 ]. In the 3D sphere model, the newly formed STB is located outside the sphere, which resembles in vivo morphology.…”

Are the Organoid Models an Invaluable Contribution to ZIKA Virus Research?

“…It has been developed a 3D cell-line-based model of human syncytiotrophoblasts, cells that lie in direct contact with maternal blood, that recapitulate the antiviral properties of primary trophoblasts through the constitutive release of type III IFNs (IFNλ1 and IFNλ2) and become resistant to ZIKV infection [119]. A similar model was suitable for studying vertical transmission, with much interest in exploring the congenital disease pathogenesis [120].…”

Self‐assembled human placental model from trophoblast stem cells in a dynamic organ‐on‐a‐chip system

“…[5][6][7] The isolated explant cultures or primary placental cells could mimic the complex composition and structure of human placenta, [8][9][10] but the use of human tissue samples is limited due to ethical concerns of tissue availability, storage and manipulation. In vitro trophoblast cell culture models, such as BeWo 11,12 and Jeg-3 13,14 cell lines and human induced pluripotent stem cells (hiPSCs) 15 have been used to construct placental barrier, but they are often inadequate to recapitulate the complex placental architectures and functions due to abnormal cell phenotype or immature functions of trophoblasts.…”