Prospective Procedures for Curing Azoospermia with Stem Cells.

<p>In many cases of spermatogenic failure, healthy sources of spermatogonia could be obtained from either a biopsy of an azoospermic patient's own testis, or prospectively, from a biopsy of his own somatic cells following induction into a pluripotent state. Pure spermatogonial lines derived from either source would require that they are maintained in a spermatogenic lineage and prevented from acquiring a pluripotent state when in culture. If such protocols were established, naturally healthy spermatogonial lines could be selected for from a background of potentially unhealthy cell lines, such as from cancer patients, or azoospermic men diagnosed as germline mosaics (later example is shown). Once selected for, the healthy lines could then be induced to develop into sperm by transplanting them back into the patient's own testes. As potential alternatives to sterile-testis complementation that are currently being investigated, spermatogonial stem cells could be induced to develop through meiosis during culture <i>in vitro</i>, or within tissue grafts for production of haploid gametes <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0006308#pone.0006308-Honaramooz1" target="_blank">[50]</a>. The resulting haploid spermatids could then be used for assisted fertilization.