Oral Presentation Australia and New Zealand Society for Extracellular Vesicles Conference 2025

Exploring the cellular origins of seminal extracellular vesicles (127005)

Elizabeth Torres Arce 1 2 , Hui-Ming Zhang 3 , Amanda L Anderson 1 2 , Shanu Parameswaran 1 2 , Judith Weidenhofer 4 5 , Sarah A Robertson 6 , Brett Nixon 1 2 , David J Sharkey 6 , John E Schjenken 1 2
  1. School of Environmental and Life Sciences, College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW 2308, Australia
  2. Hunter Medical Research Institute, Infertility and Reproduction Research Program, New Lambton Heights, NSW 2305, Australia
  3. Central Analytical Facility, Research and Innovation division, University of Newcastle, Callaghan, NSW 2308, Australia
  4. School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle, Ourimbah, NSW 2258, Australia
  5. Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
  6. The Robinson Research Institute and School of Biomedicine, University of Adelaide, Adelaide, SA 5005, Australia

Introduction: Seminal extracellular vesicles support sperm development and influence the female tract immune response. These EVs are thought to be primarily secreted by the prostate(1), but emerging evidence suggests cells throughout the male reproductive tract release EVs.

Methods: EVs secreted by the testis, epididymis, vas deferens, seminal vesicles, and prostate of mice were isolated using differential ultracentrifugation, then characterised using Nanoparticle Tracking Analysis (NTA) (assessing EVs collected from 16 mice), Transmission Electron Microscopy (TEM) and Immunogold labelling (both assessing EVs collected from 4 mice).

Results: NTA revealed fluids from the prostate and seminal vesicles had high concentrations of  EVs, while the testis, epididymis (Caput, Corpus and Cauda), and vas deferens fluids were lower. TEM showed variation in EV size with significantly larger EVs (p<0.05) secreted by the seminal vesicles and prostate compared to EVs secreted by the testis, caput, corpus, cauda, and vas deferens. Flotillin-1+ and CD63+ EVs were detected across all male reproductive tract regions using immunogold labelling, with significantly larger (p<0.05) Flotillin-1+ and CD63+ EVs in the testis compared to those secreted from the seminal vesicles, prostate, corpus and cauda. To begin to identify markers for the origins of seminal EVs, immunogold labelling showed the seminal vesicle marker, Mucin-6, in seminal vesicle but not prostate-derived EVs. In contrast, the prostate specific marker Transglutaminase-4 was detected in both seminal vesicle and prostate-derived EV populations.

Conclusions: These data confirm EVs are secreted by cells across the male reproductive tract, potentially contributing to the heterogeneous seminal EV population.

  1. Tamessar CT, Trigg NA, Nixon B, Skerrett-Byrne DA, Sharkey DJ, Robertson SA, et al. Roles of male reproductive tract extracellular vesicles in reproduction. Am J Reprod Immunol. 2021;85(2):e13338.