Normal expression levels of cathepsins, protease inhibitors, andSp1 in conjunctival tissues from patients with keratoconus.

Maruyama, Ikuyo; Zhou, LiLi; Sugar, Joel; Yue, Beatrice Y.J.T.

PURPOSE. In keratoconus corneas, it has been shownthat levels of degradative enzymes and transcription factor Sp1 are elevatedand those of inhibitors are reduced, especially in the epithelial layer. Thisstudy is to determine whether the biochemical abnormalities identified incorneas also exist in conjunctival tissues. METHODS. Conjunctival tissues were collected from normal subjects and frompatients with keratoconus, senile cataract, and other corneal diseases. Immunohistochemicalstaining for cathepsins B and G, α1-proteinase inhibitor, α2-macro-globulinand Sp1 was performed. RESULTS. The epithelium of all conjunctival specimens showed immunoreactivitytoward the antibodies. The staining for cathepsins B and G, and the inhibitorswas mostly cytoplasmic, while that for Sp1 was nuclear. The staining intensityin keratoconus specimens was all within normal range. CONCLUSIONS. These results suggest that the abnormalities in cathepsinsB and G, protease inhibitors and Sp1 identified in keratoconus corneas arenot manifested in the conjunctiva. Keratoconus appears to be a disease localizedto the cornea.

KERATOCONUS; CONJUNCTIVA; PROTEASE inhibitors

Current Eye Research, 2000, Vol 21, Issue 5

0271-3683

Academic Journal

10.1076/ceyr.21.5.886.5538