Final answer:
The blood-testis barrier, formed by tight junctions between Sertoli cells, prevents immune attacks on sperm and blocks harmful substances from the bloodstream, ensuring the protection and regulation of spermatogenesis.
Step-by-step explanation:
The blood-testis barrier (BTB) plays a crucial role in protecting spermatogenesis by forming tight junctions between Sertoli cells in the testes. This barrier has two main functions: it prevents immune system cells from reaching and potentially attacking developing sperm cells, safeguarding them from an autoimmune response, and it keeps bloodborne pathogens and substances from interfering with spermatogenesis.
Sertoli cells also nurture and support the development of sperm by secreting substances that promote sperm production and decide the fate of germ cells. They are, therefore, indispensable to maintaining a healthy and functional male reproductive system. The tight junctions between the sustentacular cells create a barrier that keeps out bloodborne substances and prevents surface antigens on germ cells from escaping into the bloodstream.