Procoagulant tissue factor-exposing vesicles in human seminal fluid.

Area of Science:

• Reproductive Biology
• Hematology
• Cell Biology

Background:

• Vesicles like microparticles (MP) and exosomes are found in various bodily fluids.
• These vesicles are involved in coagulation, inflammation, and cell signaling.
• Seminal fluid contains vesicles, but MP and exosomes have not been fully characterized.

Purpose of the Study:

• To analyze and characterize vesicles in seminal fluid.
• To investigate the role of seminal fluid vesicles in male partners of patients undergoing IVF/ICSI.
• To determine the procoagulant properties of seminal fluid-derived MP.

Main Methods:

• Flow cytometry (FACS) and transmission electron microscopy (TEM) were used to detect and analyze MP.
• Antibodies against tissue factor (TF), CD10, CD13, CD26, and annexin V were employed.
• Fibrin generation tests assessed the coagulant properties of the vesicles.

Main Results:

• Microparticles (MP) were detected in human seminal fluid using both FACS and TEM.
• Seminal fluid-derived MP expressed CD10, CD13, CD26, and tissue factor (TF).
• The identified MP exhibited high procoagulant activity, strongly activating the extrinsic pathway of coagulation.

Conclusions:

• Seminal fluid contains procoagulant microparticles expressing specific markers.
• These microparticles are potent activators of the extrinsic coagulation pathway.
• The contribution of seminal fluid MP procoagulant activity to human reproduction and implantation requires further investigation.