Researchers at Karolinska Institutet announced on July 3 that they have successfully created early germ cells from preserved testicular tissue of young boys who underwent cancer therapy. The findings, published in the journal Human Reproduction Open, may lead to new methods for protecting and restoring fertility in childhood cancer survivors.
Children receiving intensive cancer treatments are at risk of infertility because these therapies can damage the cells that eventually develop into sperm. In this study, researchers explored whether remaining cells in the testicle could be used to recreate sperm precursors.
The team utilized frozen testicular tissue from two prepubertal boys previously treated for cancer with very few remaining germ cells. Supporting cells were isolated and reprogrammed into induced pluripotent stem cells, which can become various cell types. These stem cells were then directed to develop into primordial germ cells using a clinically compatible protocol designed for future translational applications. The reprogrammed stem cells passed standard quality checks and showed relatively high efficiency when converted into early germ cells through two different methods.
This work is described as a proof-of-concept study, indicating that while the experimental approach is feasible, it is not yet ready for clinical use. Additional research will be required to confirm the robustness of these results, further mature the derived germ cells, and ensure safety before considering any clinical application.
"In the short term, the findings will contribute to understanding how cancer treatment affects germ cells and the regenerative potential of the preserved tissues, helping us to develop protective strategies. In the long term, it could pave the way for new regenerative treatments to restore fertility in cancer survivors," said João Pedro Alves-Lopes, leading author and researcher at Karolinska Institutet.
The study was conducted in collaboration with NORDFERTIL consortium partners including Karolinska University Hospital as well as universities and hospitals across Sweden, Finland, and Belgium. Funding was provided by several organizations such as Birgitta and Carl-Axel Rydbeck's Research Grant for Paediatric Research, Swedish Research Council, Swedish Childhood Cancer Foundation, and international research programs.
