Jager et al. demonstrated that CAT-1 activity does not change in inflammatory ocular surface conditions such as keratoconus, Fuchs' dystrophy, and herpetic keratitis, and CAT-2 increases significantly in these tissues and in response to the stimulation by the supernatant of Pseudomonas aeruginosa [45]. This evidence concerns the gene SLC7A2 and keratoconus.