Dobrinski, InaSakib, Sadman2022-11-152022-04-20Sakib, S. (2022). Novel Culture Systems for Studying Proliferation and Maturation of Spermatogonia in vitro (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/115440https://dx.doi.org/10.11575/PRISM/40407The work presented in this dissertation aims to establish two novel culture systems for the proliferation and differentiation of spermatogonia. First, we established a suspension culture system for porcine spermatogonia using stirred suspension bioreactors. We showed that porcine pre-pubertal spermatogonia have a higher degree of proliferation in suspension culture compared to static culture. We also show that while spermatogonia proliferate more under ambient O2 compared to lower O2 tension of 10%, they are also likely to undergo differentiation. Our findings indicate that the higher proliferation of spermatogonia that is observed in suspension culture is partially mediated by the Wnt/ ?-catenin pathway. Other signal transduction pathways may also be activated in the stirred suspension bioreactor. This lays the foundation for future work aimed towards better understanding and improvement of suspension culture for spermatogonia. Second, we established a primate, human, mouse, rat and porcine testicular organoid system using the microwell culture system. We find that these organoids have testis-specific morphology and mimic testicular functions. We also present evidence that the mouse and rat organoids can undergo maturation and promote differentiation of spermatogonia. Our proof-of-principle experiments with ciliobrevin D, mono-2-ethylhexyl phthalate and cadmium chloride indicate that testicular organoids can serve as a platform for modeling testis morphogenesis and reproductive toxicity in vitro. In summary, the organoid platform established for this dissertation opens up an exciting avenue of research to further develop and adapt the system for studying the human male reproductive system in vitro in a tissue specific context.enUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Germ cellSpermatogoniaStirred suspension bioreactorTestesTesticular organoidSpermatogenesisBiological SciencesBiology--CellBiology--Veterinary Sciencedoctoral thesis