Rapid appearance of plasmin in tear fluid after ocular allergen exposure

Specific allergens were applied topically to the conjunctivae of 18 allergic patients. In cases with positive allergic reaction, proteolytic activity, identified as plasmin using zymographic analysis and a monoclonal anticatalytic antibody to plasmin, was found to appear within 3-5 min in the tear fluid, reaching concentrations of 2.2-28.6 micrograms/ml. No plasmin was detected, either in the tear fluid of 30 unchallenged non-atopic control persons, or atopic patients provoked with a test material that had given no reaction in a skin prick test. These findings suggest that generation of plasmin is a consequence of the conjunctival allergic reaction.