Effects of gene transfer into keratocytes on corneal wound healing after excimer laser keratectomy

Purpose. To determine the potential o "somatic gene transfer with the herpes simplex virus thymidine kinase (HStk) gene ;is a technique for modulating corneal wound healing after superficial keratectomy. Methods. PTK in a depth of 100 microns was performed in 8 rabbit corneas. E> pression of the 8-gaIactosidase gene was demonstrated with histochemical stair ing. Four rabbits were transduced with vector containing the Hstk gene, and a control group of four eyes was transduced with "empty" vector. Topical ganciclovir (20 mg/ml) was subsequently applied for 10 days during the postoperative period. I'ost-surgical comeal haze was measured using a standardized videographic techn que with computerized image analysis to quantitate corneal opacity. Results. Expression of β-galactosidase within vimentinpositive corneal stromal cells confirmed transduction of keratocytes in the rabbits. The combination of Hstk gene transfei and topical ganciclovir reduced postoperative corneal opacity compared to controls (P=0.03). Conclusions. The ability to genetically transduce stromal keratoc;/tes provides a new strategy for manipulating the important cellular and molecular el ents that influence corneal wound healing, thus offering a potential approach to prevent scarring after excimer keratectomy.