Current Understanding of the Physiology and Histology of Human Spermatogenesis

Spermatogenesis is a complex process that ensure daily production of mature male gametes. The differentiation of spermatogonia stem cells into spermatozoa requires the unfolding of several events which are highly regulated in time and space. During spermatogenesis, which takes place inside the seminiferous tubules, germ cells undergo profound morphological rearrangement as can be observed by classical histological analysis of human testis specimens. Spermatogenesis also brings about the dramatic rearrangement of genetic makeover of developing germ cells including homologous recombination and changes in the epigenetic landscape. In this chapter the different phases of human spermatogenesis and cell types involved are described with an emphasis on their morphological arrangements. In parallel, an update on novel findings concerning the cycle of the seminiferous epithelium, the kinetic of spermatogonial compartment and the implications of single cell transcriptome analysis of testicular cells will be provided