Purpose: To evaluate the expression of tissue inhibitor of metalloproteinases (TIMP) mRNA in corneal tissues before and at early time points (6 and 12 hours and 1, 3, and 5 days) after corneal infection with Pseudomonas aeruginosa.
Methods: Ribonuclease protection assays were used to detect and quantitate TIMP mRNA expression in uninfected (wounded and unwounded) and in wounded corneas inoculated with P. aeruginosa.
Results: Expression of TIMP-1 mRNA was undetectable in either wounded or unwounded, uninfected corneal tissues, but it increased in a time-dependent manner with peak expression occurring at 3 days after corneal wounding and bacterial inoculation. Constitutive low-level mRNA expression of TIMP-2 was detected in both groups of uninfected corneal tissues; these groups remained essentially unchanged after corneal abrasion and bacterial inoculation. TIMP-3 mRNA was detected in uninfected (wounded and unwounded) corneal tissues and appeared to decrease in a time-dependent manner after corneal abrasion and bacterial inoculation.
Conclusions: The evidence indicated that TIMPs were expressed in infected and in uninfected (wounded and unwounded) corneal tissues. In addition, these data suggested that TIMP expression appeared to be independently regulated.