Emergent roles for intercellular adhesion molecule-1 in the restructuring of the blood-testis barrier during spermatogenesis in the mammal.

Mammalian spermatogenesis is comprised of a series of molecular, cellular, and morphological events that underscore the movement of developing germ cells across the blood-testis barrier. These events involve the restructuring of tight junctions, basal ectoplasmic specializations, gap junctions, and desmosomes, which constitute blood-testis barrier function. Previous studies show that preleptotene/leptotene spermatocytes traverse the blood-testis barrier while transiently trapped within an intermediate compartment, which sequesters primary spermatocytes away from basal and adluminal compartments of the seminiferous epithelium. Preleptotene/leptotene spermatocytes enter the adluminal compartment when stable junctions ahead of spermatocytes disassemble, while new junctions assemble behind them. While there is enormous restructuring of the seminiferous epithelium, the mechanism of germ cell movement is incompletely understood. In this perspective, the significance of intercellular adhesion molecule-1 in the restructuring of the blood-testis barrier during spermatogenesis in the mammal is discussed.