A tiny group of cells has been identified by researchers at the University of Edinburgh that appears to be responsible for repairing damage to the testes. The study, published in the Journal of Experimental Medicine, may offer a novel approach for preserving fertility in boys undergoing cancer treatment.

The testes are extremely sensitive to damage from external factors, including the radiation and chemicals sometimes used to treat cancer. As a result, male patients who have undergone radiotherapy or chemotherapy are likely to have fertility problems later in their lives. Older patients are able to freeze a sample of their sperm before their treatment but prepubescent boys do not have this opportunity as their sperm has not yet developed.

This new research may be able to help patients in this position. The team were able to use molecular tools to identify a very small group of cells called Miwi2-expressing cells, which seem to be involved in repairing testes damage in mice. The model allowed the researchers to observe how mice without the cells were unable to recover from damage that their healthy littermates recovered from without difficulties.

“In identifying this key group of cells, we have made a significant step in understanding cell repair in the testes,” said Professor Dónal O’Carroll, stem cell biologist at the University of Edinburgh. “Our study with mice suggests that it may be beneficial to also freeze additional cells in order to maximise chances of future treatments. Our next step is to identify the equivalent group of cells in humans.”