O-137 Evaluation of the effect of seminal plasma exosomes from unexplained infertile men on the expression of implantation-related genes
Authors: Gholipour H , Bakhtiyari M , Amjadi F.S , Mehdizadeh M , Aflatoonian R , Zandieh Z 
Published: June 2022

Study question

Do exosomes from seminal plasma of men with unexplained infertility affect endometrial receptivity?

Summary answer

Seminal plasma exosomes from unexplained infertile men alter the expression of genes and signaling pathways related to endometrial receptivity.

What is known already

Unexplained infertile Men are a challenging group with no obvious cause of infertility. Many Complicated mechanisms play a crucial role in preparing the receptive endometrium for embryo implantation. The exosomes of seminal plasma are a heterogeneous cargo of nucleic acids, proteins, and lipids that participate in sperm maturation and function by binding to sperm. It is now apparent that the seminal plasma and its exosomes play a complex role in controlling the female reproductive system. There is no study investigating the effect of Unexplained seminal plasma exosomes on endometrial receptivity.

Study design, size, duration

Samples were collected from 10 men with normal semen parameters from couples undergoing infertility treatment and from 10 donor men with proven fertility and analyzed according to WHO -2010 criteria. Endometrial biopsy tissue was collected from 6 women in the proliferative phase of a natural menstrual cycle. Endometrial epithelial cells were cultured immediately after tissue processing and treated with 100 μg/ml seminal exosomes for (6 and 24 hours); then analyzed for gene expression.

Participants/materials, setting, methods

Exosomes isolated by an ultracentrifuge and characterized size and ultrastructure with dynamic light scattering and transmission electron microscopy. Western blot analysis showed the presence of the exosome markers. After incubation of exosomes with DiI dye, cytoplasmic localization of exosomes detected by fluorescence microscopy. The endometrial receptivity and signaling pathway genes were analyzed by qRT-PCR and immunocytochemistry. Image J and Prism software were used to quantify and analyze the data. P-value &lt;0.05 was considered statistically significant.

Main results and the role of chance

Compared with the embryo donation group, the mRNA levels of MUC1, LIF, G-CSF, CX3CL1, and VEGF were significantly downregulated in the endometrium treated with unexplained infertile exosomes, especially after 24 hours of treatment. Mean mRNA levels of IL6, IL8, and TGFB genes in the unexplained infertile group changed compared with the embryo donation group but were not significant (p &gt; 0.05). Immunocytochemical analysis showed that  MUC1 and LIFR protein levels were increased in endometrial epithelial cells.

Limitations, reasons for caution

larger sample size and exosomal compositions assessment will be useful to identify the effect of exosomes on the endometrium.

Wider implications of the findings

Alterations in the expression of genes associated with endometrial receptivity by exosomes of the unexplained infertile men compared with embryo donation could be one of the causes of infertility in these individuals. Presumably, the atypical composition of exosomes has a different effect on sperm functions and endometrial genes expression.

Trial registration number

Not applicable