Effects of human chorionic gonadotropin-producing peripheral blood mononuclear cells on the endometrial receptivity and implantation sites of the mouse uterus

Exosomes as modulators of embryo implantation

Exosomes, known as extracellular vehicles (EVs), are found in biological fluids. They have the capability to carry and transfer signaling molecules, such as nucleic acids and proteins, facilitating intercellular communication and regulating the gene expression profile in target cells. EVs have the potential to be used as biomarkers in diagnosis, prognosis and also as feasible therapeutic targets. The available evidence suggests that exosomes play critical roles in the reproductive system, particularly during implantation, which is widely recognized as a crucial step in early pregnancy. A proper molecular dialogue between a high-quality embryo and a receptive endometrium is essential for the establishment of a normal pregnancy. This review focuses on the key role of exosomes originated from various sources, including the embryo, seminal fluid, and uterus fluid, based on the available evidence. It explores their potential applications as a novel approach in assisted reproductive technologies (ART).

Intrauterine administration of autologous peripheral blood mononuclear cells regulates the endometrium estrogen and progesterone receptor expression: An RCT

Background

Repeated implantation failure (RIF) affects 15% of women of reproductive age. There is a high endometrial expression of both estrogen receptors and progesterone receptors (PRs) during the window of implantation in women with RIF.

Objective

To evaluate the effects of intrauterine administration of human peripheral blood mononuclear cells (PBMC) on estrogen receptor α (ERα) and PRs expression in the endometrium of women with RIF during the implantation window.

Materials and Methods

This randomized clinical trial study was conducted on 22 women with RIF history from January 2018 to August 2019 in Erfan hospital, Tehran, Iran. Participantswere divided into 2 groups (PBMC-treated group [n = 11] and control group [n = 11]). Endometrial tissue samples were collected at the implantation window time, during the mid-secretory phase (luteinizing hormone surge +7 days) of each menstrual cycle. The quantitative real-time polymerase chain reaction technique was used to measure the mRNA levels of ERα and PRs isoforms (PR-A and PR-B) in endometrial tissues. Furthermore, the protein expression of ERα and PRs was investigated using immunohistochemical staining.

Results

PBMC treatment significantly decreased the mRNA expression of endometrial ERα and PRs isoforms at the time of the implantation window (p < 0.001). Moreover, the endometrial ERα and PRs protein localization were significantly lower in PBMC-treated women compared with controls (p = 0.01, and p < 0.001 respectively).

Conclusion

The intrauterine administration of PBMC decreased the endometrial ERα and PRs expression during the window of implantation in women with RIF. This local response to PBMC therapy could promote endometrial receptivity and embryo implantation.