In recurrent corneal erosions, which cell junction is the main adhesion structure at the epithelial basement membrane?

• A. Hemidesmosomes
• B. Desmosomes
• C. Macula Occludens
• D. Zonula Occludens

Answer: (A)

Hemidesmosomes anchor the epithelial layer to the basement membrane, providing the main adhesion that keeps the corneal epithelium attached to its underlying support. In the cornea, these structures link keratin filaments inside basal epithelial cells to components of the basement membrane—via integrins such as α6β4 and proteins like BP180 (collagen XVII) and laminin-332—creating a strong, stable connection. In recurrent corneal erosions, a defect in this adhesion allows the epithelial cells to detach from the basement membrane after minor trauma, leading to recurrent slipping and erosion.

Desmosomes, by contrast, hold neighboring epithelial cells together, but not to the basement membrane. Tight junctions (macula occludens and zonula occludens) create a seal between cells to regulate paracellular movement, not anchor to the basement membrane.