Purification and culture of primate/human spermatogonial stem cells

Project Gist

Establishment of a long-term culture system for human/primate spermatogonial stem cells

Keywords

Spermatogenesis, Stem cell, Culture, Male infertility, Transplantation

Background and Purpose

Recent development of cancer therapy has improved the survival rate of cancer patients. However, such treatments often causes male infertility due to destruction of germ cells. Although it is possible to store sperm from adult males, it is impossible to protect fertility of prepubertal boys who do not have sperm. Spermatogonial stem cell (SSC) culture and transplantation are considered to be a valuable solution to this problem. However, very little is known about the biology of primate/human SSCs.

Project Achievements

For transplantation therapy of male infertility, it is necessary to establish a culture system for SSCs to expand their number in vitro. However, very little information is available for gene expression patterns in human SSCs, and critical growth factors for human SSCs have not been identified. In this project, we identified a novel tyrosine kinase receptor on human SSCs. By using antibodies against this molecule, it is possible to collect a highly purified SSC population. Because this molecule enhances self-renewal signals in mouse SSCs, we expect that stimulation of this molecule will be useful for establishing a long-term culture system for human SSCs.

Future Prospects

My immediate goal is to develop a long-term culture system for human spermatogonial stem cells. Although it is difficult to obtain human testis samples in Japan, they are now readily available by collaboration with US researchers through SPIRITS project. In the future, I would like to make a culture system for in vitro spermatogenesis.

Figure

Joint Research/Academic Institutions Abroad

University of Pittsburgh, Utrecht University

Principal Investigator