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Sperm Travels

Greater understanding of vessel development in the epididymis revealed by 3D imaging

09 July 2023

Sperm Travels

Human sperm go on quite the journey before finally being released. Over 4 to 6 weeks, developing sperm travel through a long, winding tube called the epididymis, which exits the testes and heads to the penis. The epididymis helps developing sperm mature but also has a role in immunity, which affects male fertility. Researchers now probe its immune role by mapping out key structures of its immune system: epididymal blood and lymphatic vessels. Mice were genetically engineered with fluorescently-tagged lymphatic vessels. Epididymal tissue was collected from these newborn and adult mice, fluorescently labelled for other lymphatic and blood vessel markers and treated to make it transparent. High-resolution 3D imaging (pictured) revealed detailed 3D views of lymphatic (pictured) and blood vessel networks, which shed light on their development, including the fact that lymphatic vessels closely follow fibrous partitions (white) in the epididymis called septa.

Written by Lux Fatimathas

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