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May 20-21, 2019 | Rome, Italy
Journal of Cell Science and Mutation | Volume 3
OF EXCELLENCE
IN INTERNATIONAL
MEETINGS
YEARS
Stem Cell Congress 2019
STEM CELLS AND REGENERATIVE MEDICINE
2nd International Conference on
GONOCYTE TRANSFORMATION INTO SPERMATOGONIAL STEM CELLS: THE KEY TO UN-
DERSTAND INFERTILITY AND MALIGNANCY OF CRYPTORCHIDISM
Ruili Li1,2 , Amanda Vannitamby1, Sarah S K Yue1, Jorien Meijer1, Moshe Loebenstein 1, Vanessa
Wilson1, Emily C Burton1, Melissa Y Tien1 and John Hutson1,2,3
1 Murdoch Children’s Research Institute, Australia
2 University of Melbourne, Australia
3 Royal Children’s Hospital, Australia
Undescended testis (UDT) is a major health problem, affecting over 2% of new-born boys with increased
infertility (30-60%) and testicular cancer (5-10 fold higher than normal males) later in life. Author have
studied animal models in conjunction with human biopsies of UDT in order to understand the process of gono-
cyte transformation into spermatogonial stem cells (SSC) to elucidate how to prevent infertility and testicular
cancer in cryptorchidism. We used testes from OG2 (Oct4-promoter-driving GFP transgenic mice), androgen
knockout (ARKO), Bax knockout (BaxKO) and hypogonadal (hpg) mice and human biopsies for gene expression
with real-time PCR and immunohistochemistry with antibody labelling followed by confocal imaging analysis.
Serum and testes were collected fromC57Bl/6 male mice for hormone analysis to examine mouse minipuberty.
We have found that mouse gonocyte (Oct4+/C-Kit-) transformed into SSC (Oct4+/C-Kit+) between postnatal
2-6 days. There was transient testosterone surge at postnatal day 1-3 and gene expression of both FSH receptor
and Oct4 peaked at postnatal day 3-6 inmouse. There were no difference for number of gonocytes transformed
into SSC/tubule between ARKO mice and wild type littermates. Germ cells/tubule was significantly less in hpg
mice comparing with wild-type littermates. Persisting gonocytes exist in BaxKO mouse testis and human tes-
ticular biopsies of UDT beyond six months old and germ cells/tubule significantly decreased whereas number
of empty tubules without germ cells significantly increased with increasing age of orchidopexy. In conclusion,
they found that minipuberty does exist in mouse which coincides with the gonocyte transformation into SSC
like human. Gonocyte transformation in mouse is independent from androgen and disruption of apoptosis
derange; the process causing persistent gonocytes which could be the source of malignancy. Orchidopexy at
older age showed significant germ cell depletion and persisting gonocytes. The results suggest that FSH or/
and non-androgenic factors may play an important role in gonocyte transformation into SSC.
Adv Cell Sci Mut. 2019, Volume 3