Plasminogen activator inhibitors in human tears

Area of Science:

• Ocular surface disease
• Ophthalmology
• Biochemistry

Background:

• Plasminogen activator inhibitors (PAIs) play a role in regulating protease activity.
• The presence and role of PAIs in human tears, particularly in ocular surface conditions, are not well understood.

Purpose of the Study:

• To investigate the presence and activity of plasminogen activator inhibitors in human tears.
• To determine if PAI activity in tears is associated with specific ocular surface diseases or conditions.

Main Methods:

• Tear samples were collected from patients with various corneal and conjunctival diseases, Sjögren's syndrome, and post-eye surgery.
• Plasminogen activator inhibitor activity was assessed using reverse fibrin zymography.
• Immunoblotting was employed to identify the types of PAIs present (Type 1 and Type 2).

Main Results:

• Plasminogen activator inhibitor activity was detected in tears from patients with corneal and conjunctival diseases, Sjögren's syndrome, and after eye surgery.
• Both Type 1 and Type 2 plasminogen activator inhibitors were identified in tears when ocular surface epithelia were affected or conjunctival blood vessel permeability increased.
• No PAI activity was found in tears from healthy individuals.

Conclusions:

• The presence of plasminogen activator inhibitors in human tears is associated with pathological events at the ocular surface.
• PAIs may play a role in the inflammatory and healing processes of various ocular surface diseases.