Adhesive mechanisms of the corneal epithelium

The corneal epithelium adheres to the stroma through a series of linked structures termed collectively the adhesion complex. These structures include; intermediate filaments (keratin filaments) which are linked to the hemidesmosome; the hemidesmosome; the anchoring filaments which extend from the membrane at the hemidesmosome through the lamina lucida to the lamina densa region of the basement membrane; the anchoring fibrils which insert into the basement membrane from the stromal side; and the anchoring plaque on which anchoring fibrils terminate distal from their insertion on the basement membrane. Upon wounding, basal cells of the corneal epithelium disassemble their hemidesmosomes. During migration, the membranes along the wound bed exhibit a different kind of adhesion junction, the focal contact. This junction is present primarily in cells of the leading edge of migration and may be the provisional adhesion junction used by epithelial sheet moving to cover a wound.