The spermatogonial stem cell: from basic knowledge to transgenic technology.
Differentiation of germ cells in the testis originates from a constantly renewed small pool of stem cells. They give rise to the first differentiated spermatogenic cells (spermatogonia). These committed cells will then follow a strictly defined succession of steps, starting with six synchronized mitotic cycles before reaching the first meiotic stages. Following a first identification of the spermatogonial stem cells on morphological and cytological criteria, a functional assay was devised, based on their ability to repopulate the testis of a sterile recipient. Purification and characterization of the stem fraction is in progress. Fundamental knowledge of the biology of the germ line and preclinical studies in several important fields will benefit of these advances, while gene transfer prior to reimplantation opens a new approach in transgenic technology.
Unité 636 de l'Institut de la Santé et de la Recherche Médicale, Faculté des Sciences, Université de Nice-Sophia Antipolis, 06108 Nice cedex 2, France.
Virginie
V
Olive
François
F
Cuzin
D000818:Animals; D018014:Gene Transfer Techniques; D006801:Humans; D007248:Infertility, Male / Q000209:etiology / Q000473:pathology; D008297:Male; D012671:Seminiferous Tubules / Q000473:pathology / Q000502:physiology*; D013093:Spermatogonia / Q000473:pathology / Q000502:physiology* / Q000637:transplantation; D013234:Stem Cells / Q000473:pathology / Q000502:physiology*; D013736:Testicular Neoplasms / Q000209:etiology / Q000473:pathology; D019076:Transgenes