Advanced 3Dimentional engineered microenvironment to improve of in vitro spermatogenesis: narrative review

Induction of in vitro spermatogenesis may be helpful in the treatment of infertility in azoospermic individuals and those undergoing chemotherapy. Different cultivation systems have been implemented to achieve this aim. This review study aimed to investigate the application of three-dimensional culture in the induction of in vitro spermatogenesis. Relevant studies published in English were identified using PubMed using a range of search terms related to the core focus on tissue engineering of male reproductive systems, in vitro spermatogenesis, germ cell preservation, 3D culture systems for in vitro spermatogenesis, a 3D culture of testis tissue with were last updated in end of 2023. Searches were not restricted to a particular time frame or species, although the emphasis within the review is on regenerative medicine in mammalian male fertility preservation and in vitro spermatogenesis. Spermatogenesis is one of the most complicated cellular differentiation processes in the body. Significant attempts have been made to control spermatogenesis to drive differentiation of male germ stem cells toward mature sperm. Current research efforts focus on providing appropriate microenvironmental conditions to support the process of in vitro spermatogenesis by applying the principles of cell transplantation, material science, and bioengineering. Regenerative medicine may open a new avenue to patients for restoration and maintenance of normal function in spermatogenesis. The techniques reviewed are still in development, and this paper can become the primary reference for a large body of scientists developing advanced tissue engineering for male germ cells or developing the next generation of reproductive medicine.