Additional Evidence to Establish Existence of Two Stem Cell Populations Including VSELs and SSCs in Adult Mouse Testes


Present study aims to describe a simple and robust protocol to delineate the presence of pluripotent, very small embryonic-like stem cells (VSELs) in addition to spermatogonial stem cells (SSCs) in adult mouse testes. Testicular seminiferous tubules were subjected to enzymatic dissociation to obtain single cells suspension. Stem cells were enriched by spinning at different speeds wherein majority of somatic cells were pelleted at 1000 rpm (250 g, Pellet A) and putative stem cells by spinning the supernatant (obtained after separating Pellet A) at 3000 rpm (1000 g, Pellet B). Viable (7AAD-ve), 2–6 μm, LIN-CD45-SCA-1+ VSELs were studied after doublets exclusion by flow cytometry in both Pellets A & B. Almost ten-fold enrichment of VSELs was obtained in Pellet B (0.27 + 0.05%) compared to Pellet A (0.03 + 0.003%). SCA-1 expressing SSCs (>6 μm, 0.18 + 0.06%) were clearly distinguished from VSELs (2–6 μm, 0.07 + 0.003%) by flow cytometry studies on total testicular cells suspension collected by spinning at 3000 rpm. Enriched stem cells from Pellet B were used to study expression of OCT-4, NANOG, SCA-1, SSEA-1, LIFR, GFRa, c-KIT, ERα and ERβ. Cells in Pellet B were also subjected to RT-PCR to study pluripotent (Oct-4a, Sox2, Nanog), primordial germ cells (Stella, Fragilis), SSCs (Oct-4) and estrogen receptors (ERα and ERβ) specific transcripts. qRT-PCR analysis showed >2 folds up-regulation of stem cell markers in Pellet B (Oct-4A, Oct-4, Sox2, Nanog) compared to Pellet A. To conclude, spinning at higher speed led to successful enrichment of pluripotent VSELs from testes which have remained ignored till now. Expression of ERα & β on VSELs/SSCs makes them vulnerable to endocrine disruption.

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We are thankful to Indian Council of Medical Research for providing financial support and to UGC fellowship (11-04-2016-329600) to AK. Authors are thankful to the Central Facilities at the Institute for their help [NIRRH/MS/RA/851/12-2019].

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All information and detailed protocols are provided in the main article itself.

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DB planned and designed the study. AK performed all the experiments. Data interpretation, manuscript preparation was done by both and both read and agreed to final version of the manuscript.

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Correspondence to Deepa Bhartiya.

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Kaushik, A., Bhartiya, D. Additional Evidence to Establish Existence of Two Stem Cell Populations Including VSELs and SSCs in Adult Mouse Testes. Stem Cell Rev and Rep (2020).

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  • Testis
  • Stem cells
  • Spermatogonial stem cells
  • Very small embryonic-like stem cells
  • Pluripotent
  • Primordial germ cells