Poster Presentation ESA-SRB 2023 in conjunction with ENSA

Defining the immune cell profile of the mouse seminal vesicle (#384)

Shanu Parameswaran 1 2 , Jemma Mayall 3 , Fengyun Sun 4 , Amanda L Anderson 1 2 , Brett Nixon 1 2 , Sarah A Robertson 5 , Oliver J Rando 4 , John E Schjenken 1 2
  1. Infertility and Reproduction Research Program. Hunter Medical Research Institute, Hunter Medical Research Institute and School of Environmental and Life Sciences. University of Newcastle, Australia, New Lambton Heights, New South Wales, Australia
  2. Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, College of Engineering, Science and Environment, The University of Newcastle, Callaghan, NSW, Australia
  3. Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and The University of Newcastle, New Lambton Heights, NSW, Australia
  4. Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
  5. Robinson Research Institute and School of Biomedicine, University of Adelaide, Adelaide, SA, Australia

Among the male accessory sex glands, the seminal vesicles and their secretions are the chief contributor to seminal plasma in all mammalian species. The bioactive factors secreted by the seminal vesicles play a pivotal role in supporting sperm survival and function, and modulate the female reproductive tract to facilitate implantation, thereby influencing developmental programming of offspring phenotype. However, there is little information on how seminal vesicles regulate synthesis and secretion of such factors. Given immune cells regulate secretory activity in other mucosal surfaces, this study aimed to assess immune cell profiles in the mouse seminal vesicles. To achieve this, we initially mined a recent high-throughput single-cell RNA sequencing dataset of adult mouse seminal vesicle tissue to identify immune cell populations that reside in this tissue. Immune cells identified from this analysis were then confirmed by flow cytometry and immunofluorescence using seminal vesicle tissue from adult Swiss mice. Analysis of single cell RNA-sequencing data identified that immune cells residing within mouse seminal vesicles primarily consist of macrophages, as well as dendritic cells, T cells, and natural killer (NK) T cells. Flow cytometry and immunofluorescence assessment confirmed these findings with the most prevalent immune cell population being F4/80+ macrophages (40% of CD45+ cells), followed by NKP46+ natural killer (NKP46+, likely NKT cells, 35% of CD45+ cells), CD4+ T cells (8% of CD45+ cells), and CD11c+F4/80- dendritic cells (6% of CD45+ cells). Interestingly, populations of F4/80+ macrophages were found in close proximity to epithelial cells, highlighting their potential to influence secretory function as occurs in other mucosal tissues. Our current studies will further characterise the macrophage subtypes present in seminal vesicles. Together, these data provide a resource for investigating immune cell activity in seminal vesicles and may identify novel immune cell subtypes that influence seminal vesicle secretory activity.