Sertoli cell-only syndrome
Sertoli cell-only syndrome (SCOS), also known as germ cell aplasia, is defined by azoospermia where the testicular seminiferous tubules are lined solely with Sertoli cells. Sertoli cells contribute to the formation of the blood-testis barrier and aid in sperm generation.
Source: Wikipedia — Sertoli cell-only syndrome (CC BY-SA 4.0)