Effects of deletion of Arhgef15 gene in mouse sertoli cells on spermatogenesis

Sertoli cells, which are the only somatic cells in the seminiferous tubules, facilitate the maintenance of testicular immune privilege through the formation of the blood-testis barrier (BTB) and the expression of immunoregulatory factors. Rho guanosine exchange factor 15 (ARHGEF15) is a member of guanosine exchange factors, which are involved in cell migration, cell polarity, and cell cycle progression via activation of Rho GTPases. This study investigated the functions of ARHGEF15 in Sertoli cells during spermatogenesis using Sertoli cell–specific Arhgef15 knockout mice. The results showed that Arhgef15 deficiency in Sertoli cells affected the localization of Sertoli cell nuclei, disrupted BTB integrity, and led to premature shedding of germ cells. In Arhgef15flox/flox/Amh-Cre+ mice, the ultrastructure of the round spermatids was impaired, accompanied by acrosome degeneration, acrosomal vesicle shedding, and atrophic nuclei. Consequently, the percentage of abnormal sperm in the Arhgef15flox/flox/Amh-Cre+ epididymis was markedly elevated. RNA-sequencing analysis revealed that most of the differentially expressed genes in Sertoli cells of Arhgef15flox/flox/Amh-Cre+ mice were related to immunity. Further study revealed that the sera of Arhgef15flox/flox/Amh-Cre+ mice showed immunoreactivity against testicular lysate of wild-type mice, indicating the production of antibodies against testicular autoantigens in Arhgef15flox/flox/Amh-Cre+ mice. In conclusion, the specific deletion of Arhgef15 in Sertoli cells leads to sperm abnormality, probably by disrupting the testicular immune homeostasis, in mice. Comparative gene expression profiling analysis of RNA-seq data for the mouse of Sertoli-cell knockout Arhgef15 gene