Cell-cell Interaction, Cell Polarity, And The Blood-testis Barrier

Abstract

The study of polarity and its role in cell–cell interactions, such as spermatid polarity and adhesion in the seminiferous epithelium, and blood–testis barrier (BTB) in the testis during the epithelial cycle of spermatogenesis in recent years has yielded some unexpected and interesting observations. Similar to other polarized tissues, Sertoli and germ cells in the seminiferous epithelium express many of the component proteins of the Par-, Scribble- and Crumb-based polarity protein complexes. These polarity proteins are working in concert with non-receptor protein kinases, adhesion proteins, and cytoskeletons to confer spermatid and Sertoli cell polarity, and these proteins are also involved in germ cell transport in the epithelium during the epithelial cycle. In this review, we summarize the latest findings in the field. Based on the available data in the literature, it is increasingly clear that polarity proteins are crucial in (1) conferring spermatid and Sertoli cell polarity, (2) regulating spermatid adhesion and transport, and (3) regulating BTB dynamics in the testis during the epithelial cycle. We also highlight specific areas of research that deserve attention in future years. This information should be helpful to investigators in other blood–tissue and epithelial barriers in the field.