PAF, through a receptor-mediated mechanism, induces a specific pattern of furin, MMP, and TIMP-2 expression in corneal myofibroblasts. MMP-2 activity was unchanged by PAF treatment. These results suggest that in response to the inflammatory mediator PAF, induction of MT1-MMP is independent of MMP-2 activity in corneal myofibroblasts. Thus, PAF-mediated changes in extracellular matrix composition surrounding the myofibroblasts could be important in regulating the corneal scarring process. Moreover, PAF antagonists could be useful in maintaining corneal transparency.