In vitro demonstration of deleterious effect of steel mutation on spermatogenesis in mice

Abstract
The effect of the steel mutation on spermatogenesis was investigated by using organ culture. Cultured cryptorchid testes from C57BL/6− +/+ mice showed an effective differentiation of type A spermatogonia in response to an increased concentration of bovine serum. In contrast, the cryptorchid testes from C57BL/6 – S/d/ + mice showed only limited differentiation of type A spermatogonia even in the highest concentration of serum tested. The type A spermatogonia of mutant mice showed the normal mitotic response but did not differentiate further. The findings reported here are the first in vitro demonstration of the deleterious effects of the steel mutation on testicular germ cell differentiation and suggest that the effect of the steel mutation is expressed in Sertoli cells, the only supporting element in seminiferous tubules, or germ cells themselves.