Blood–testis barrier

Blood–Testis Barrier

The blood–testis barrier (BTB) is a physical barrier between the blood vessels and the seminiferous tubules of the testes. This barrier is formed by tight junctions, adherens junctions and gap junctions between the Sertoli cells, which are located in the seminiferous tubules and are responsible for nurturing developing sperm cells.

Structure

The Sertoli cells, which form the BTB, are columnar in shape and have a large, oval nucleus. They are connected by tight junctions, adherens junctions and gap junctions, which together form the BTB. The BTB divides the seminiferous tubule into a basal compartment, which is accessible to blood vessels and other cells of the immune system, and an adluminal compartment, which is not accessible to these cells.

Function

The primary function of the BTB is to protect the developing sperm cells from harmful substances in the blood. It also prevents the immune system from accessing the genetically different sperm cells, thus preventing an immune response. The BTB also creates a unique microenvironment for spermatogenesis, the process of sperm cell development, to occur.

Clinical significance

Disruption of the BTB can lead to infertility in males. This can occur due to exposure to toxic substances, infection, or trauma. Certain medical conditions, such as varicocele and autoimmune diseases, can also disrupt the BTB and lead to infertility.

See also

• Sertoli cell
• Spermatogenesis
• Testis
• Varicocele
• Autoimmune diseases