The Blood-Testes Barrier (BTB) acts as a physical barrier between blood vessels and seminiferous tubules of the testes. This barrier is composed of tight junctions (TJs) and adherens junctions (AJs) between sertoli cells, which are supporting cells of the seminiferous tubules that nourish the spermatogonia. In the testis, tight junctions and adherens junctions are dynamically remodeled to allow the movement of post-meiotic germ cells across the seminiferous epithelium for the timely release of spermatids into the tubular lumen. Three main functions are ascribed to the BTB: 1) To create a specialized environment, 2) To regulate the passage of molecules, and 3) To serve as an immunological barrier. When the BTB is breached and sperm enters the bloodstream, an autoimmune response against the sperm is launched...