B7-H3 promoted sperm motility in humans

Area of Science:

• Reproductive Biology
• Immunology
• Andrology

Background:

• Seminal plasma contains various proteins influencing sperm function.
• B7-H3 is an immune checkpoint molecule with potential roles beyond immunity.
• Understanding seminal B7-H3's impact is crucial for male fertility research.

Purpose of the Study:

• To investigate the correlation between seminal B7-H3 levels and semen parameters in fertile and infertile men.
• To determine the effect of seminal B7-H3 on human sperm functions in vitro.

Main Methods:

• Recruited 83 healthy donors and 176 infertile men.
• Utilized computer-assisted semen analysis (CASA) and ELISA for B7-H3 levels and semen parameters.
• Employed flow cytometry and microscopy to identify B7-H3 receptors on sperm.
• Assessed sperm motility, capacitation, and acrosome reaction after in vitro B7-H3 incubation.

Main Results:

• Seminal B7-H3 levels were significantly higher in healthy donors compared to infertile men.
• B7-H3 levels correlated positively with sperm concentration and progressive motility.
• A putative B7-H3 receptor was found on sperm, with no significant difference in expression between groups.
• In vitro, B7-H3 enhanced sperm progressive motility in a time- and dose-dependent manner.

Conclusions:

• Seminal B7-H3 positively influences human sperm motility.
• B7-H3 does not significantly affect sperm capacitation or the acrosome reaction.
• Seminal B7-H3 may play a beneficial role in maintaining sperm function.