Caldesmon transgene expression disrupts focal adhesions in HTM cells and increases outflow facility in organ-cultured human and monkey anterior segments.
Obstruction of the aqueous humor outflow from the anterior chamber of the eye leads to an elevation of intraocular pressure in glaucoma, the second major cause of blindness worldwide. Our goal is to be able to modulate aqueous humor outflow resistance by gene transfer to the cells of the trabecular meshwork (TM). We have previously shown that adenoviral vectors are able to transfer a reporter gene to the TM of post-mortem human donors. However, assessing gene therapy for glaucoma requires models that can monitor changes in aqueous humor outflow facility (C = flow/pressure). In this study we used four replication-deficient adenoviruses in two such perfusion models. In the first model, whole porcine eyes were infected, perfused at constant pressure and flow changes recorded for 5 h. In the second one, anterior segments from human eyes were infected, perfused at constant flow and pressure changes recorded for 3 days. A single dose of 108 adenovirus plaque forming units (pfu) causes a reduction in C while single doses of 107, 106 and 105 p.f.u. do not affect outflow facility and retain positive gene transfer. These findings indicate that adenovirus, at effective doses, could become useful vectors for gene therapy of glaucoma.