THE STRUCTURE AND THE INTERACTION OF THE BASEMENT MEMBRANES WITH CORNEAL STROMA

Basement membranes (BM) of the cornea of the human eye and their interactions with corneal stroma were studied using light, transmission and scanning electron microscopy. The existence of three acellular collagen-containing structures limiting was confirmed in the cornea of the human eye. BM is located under the anterior corneal epithelium and it is bound via non-fibrous extracellular matrix to the anterior limiting membrane (ALM) or the Bowman’s membrane, which is an outer part of the corneal stroma. ALM is 7-8 μm thick, and it is formed by the individual collagen fibrils with diameter of 20-40 nm, located without preferential spatial orientation. ALM collagen fibrils pass directly into flattened collagen fibers of the corneal stroma. The posterior limiting membrane (PLM) or the Descemet’s membrane, by its structure and composition, is a thickened BM (8-10 μm) of posterior corneal epithelium. Like the BM of the anterior corneal epithelium, it is associated with the collagen fibrils of the corneal stroma adjacent to it through the non-fibrous extracellular matrix and immersion of the fibrils of the corneal stroma into PLM peripheral part.

cornea, corneal stroma, anterior limiting membrane (Bowman’s membrane), posterior limiting membrane (Descemet’s membrane), basement membrane