Interaction between leucocytes and human spermatozoa influencing reactive oxygen intermediates release

Area of Science:

• Reproductive Biology
• Andrology
• Immunology

Background:

• The presence of white blood cells (WBCs) in human semen is linked to reactive oxygen intermediates (ROI) production.
• The impact of WBCs on sperm fertilizing potential remains unclear.
• Leukocytes can negatively affect sperm function through oxidative stress.

Purpose of the Study:

• To investigate the interaction between human spermatozoa and leukocytes.
• To determine the effect of different sperm preparation methods on reactive oxygen species (ROS) generation.
• To assess the capacity of prepared sperm to inhibit leukocyte-derived ROS.

Main Methods:

• Semen samples from normozoospermic men and leukocytes from healthy volunteers were used.
• Lucigenin and luminol chemiluminescence assays measured ROS generation by activated and non-activated leukocytes.
• Spermatozoa were isolated using swim-up and Percoll gradient procedures.
• Sperm motility, morphology, and viability were assessed.

Main Results:

• Swim-up separated spermatozoa significantly decreased ROS formation by leukocytes (p < 0.01).
• Spermatozoa from 90% Percoll fractions showed less inhibition of ROS compared to swim-up sperm.
• Spermatozoa from 47% Percoll fractions increased ROS signals.
• Swim-up sperm demonstrated a higher capacity to inhibit ROS secretion from stimulated leukocytes.

Conclusions:

• Normozoospermic semen may contain sperm subpopulations with varying interactions with leukocytes.
• Spermatozoa with preserved functional competence can mitigate leukocyte-derived ROS.
• Swim-up sperm preparation may enhance semen antioxidant characteristics in normozoospermic ejaculates.
• Optimized sperm preparation is crucial for assisted reproductive technologies.