Gene expression profiles of HTR8-S/Vneo cells after changes in ABCA1 expression

Gene expression pattern of trophoblast-specific transcription factors in trophectoderm by analysis of single-cell RNA-seq data of human blastocyst

The dysfunction of placenta development is correlated to the defects of pregnancy and fetal growth. The detailed molecular mechanism of placenta development is not identified in humans due to the lack of material in vivo. Trophoblast (TB) lineage derived from human embryonic stem cells (hESCs) induced by bone morphogenetic protein 4 (BMP4) has been applied as a model for studying TB lineage specification in vitro. With the development of single-cell sequencing technology, it became possible to detect the transcriptome of the post-implantation embryo at unprecedented precision. In this study, we reanalyzed single-cell RNA-seq of post-implantation embryos derived from two separate groups and identified different subtypes of trophoblast cells and their marker, respectively. At the same time, we focused on the gene expression patterns of trophoblast-specific transcription factors in different models. Our analysis sheds new light on the transcription regulation mechanism of trophoblast differentiation at the early stage of pregnancy establishment in human.

ABCA1 plays an anti-inflammatory role by affecting TLR4 at the feto-maternal interface

AIMS

This study aimed to evaluate the function and pathway of ATP-binding cassette transporter member A1 (ABCA1)-induced anti-inflammatory response in cells at the feto-maternal interface.

MAIN METHODS

The primary amniotic mesenchymal cells (AMCs), chorion cells and decidual cells were isolated from placental membranes of women with uncomplicated pregnancies at full-term (not in labor) using enzymatic digestion. Flow cytometry was used to measure the purity of isolated cells. Immunofluorescence assay was performed to detect the location of ABCA1 and toll-like receptor 4 (TLR4). Reverse transcription PCR and western blotting analyses were used to examine ABCA1, TLR4 and inflammatory factor expression in primary cells. ELISA was used to detect cytokine secretions from the primary cells.

KEY FINDINGS

ABCA1 and TLR4 were mainly located in the cell nucleus and cytoplasm of feto-maternal interface cells. ABCA1 expression remained the highest in chorion cells, medium in decidual cells, and weakest in AMCs. Upregulated expression of ABCA1 decreased expression of TLR4 and the levels of pro-inflammatory factors, but increased cytoprotective factors in all cell types. In contrast, downregulated expression of ABCA1 increased the expression of TLR4 and pro-inflammatory factors, but decreased the levels of cytoprotective factors. Downregulated ABCA1 expression followed by decreased TLR4 expression using a small interference RNA (siRNA) induced reduction of interleukin (IL)-1β and tumor necrosis factor-α (TNF-α) in all cell types.

SIGNIFICANCE

ABCA1 at feto-maternal interface acts as an anti-inflammatory role by reducing the expression of TLR4 in uncomplicated pregnancies. ABCA1 might be a potential therapeutic target for preventing gestational diseases.