Abstract
Lysosomal preparations induced marked changes in cultured corneal endothelial cells, firstly causing the epithelial-like pattern of control growth state to become multilayered and mesothelialin appearance and behavior, and secondly causing cell detachment and death. These culture changes were reversible with removal of lysosomes and restoration of fresh growth media. It appears that the changes observed were due to cathepsin, since protease with catheptic activity similar to that oflijsosomal preparations produced a similar effect, whereas the enzymes B-glucuronidase, aryl sulfatase, and acid phosphataseat concentrations found in the lijsosomal preparations did not affect the cells. Trasylal, a mucoprotein protease inhibitor, reduced cell damage, thus suggesting the involvement of a protease or cathepsin in the reaction. A parallel between cathepsin concentrationand the extent of cellular detachment was observed.