To determine whether the expression of mutant myocilin can lead to death of human trabecular meshwork (HTM) cells and to determine whether the mechanism by which this occurs is apoptosis.

HTM cells were transduced with a recombinant adenovirus expressing human mutant (Q368X) myocilin. The apoptotic death of HTM cells caused by expression of mutant myocilin was examined using a cell proliferation assay, flow cytometry, Western blot analysis, and immunocytochemistry.

It appeared that the expression of mutant myocilin itself was not sufficient to cause HTM cell death. Furthermore, the expression of mutant myocilin did not lead to apoptosis of HTM cells although it did elicit a protein unfolding response.

Our data suggest that the mechanism of myocilin glaucoma is not apoptotic death of HTM cells caused by mutant myocilin expression, and that the actual mechanism remains unknown.