Our research team studies spermatogenesis with a special focus on spermatogonial stem cells. Our current aim is to develop strategies in order to prevent infertility after gonadotoxic treatments. Fertility can be preserved by either limiting the loss of gametes and their precursors or by storing gametes and/or their precursors. Gonadotoxicity is an important side effect of cancer treatments. While adult men can bank their spermatozoa prior to such treatment, pre-pubertal children can not bank haploid gametes because they do not have active spermatogenesis. However, their testes harbour spermatogonial stem cells which eventually may be destroyed by gonadotoxic treatments, e.g. cancer treatment. Storing spermatogonial stem cells before starting gonadotoxic treatment may therefore be a strategy to prevent infertility in the long term. After being cured, spermatogonial stem cells may be reintroduced into the seminiferous tubules in order to regenerate spermatogenesis. Alternatively, testicular tissue containing spermatogonial stem cells may be grafted. Our research therefore investigates:

• The feasibility of storing spermatogonial stem cells either as a suspension or as whole tissue.
• Transplantation of spermatogonial stem cells by infusion of a cell suspension or by tissue grafting.
• The feasibility and safety of reproduction with gametes obtained after transplanting spermatogonial stem cells.
• Strategies for optimizing the regeneration of spermatogenesis from spermatogonial stem cells
• Strategies for preventing the loss of gametogenic cells by gonadotoxic treatments
• The generation of gametogenic cells from embryonic stem cells
• The pluripotency of spermatogonial stem cells