Aqueous humor protein and complement in pseudophakic eyes.

Area of Science:

• Ophthalmology
• Immunology
• Biochemistry

Background:

• Intraocular lens (IOL) insertion is standard for aphakic correction.
• Previous in vitro studies suggest IOLs activate complement, potentially causing inflammation.
• The in vivo impact of IOLs on ocular complement levels remains unclear.

Purpose of the Study:

• To investigate if IOLs influence aqueous humor (AH) levels of total protein, C3, and C3a in pseudophakic eyes.
• To compare these levels in pseudophakic eyes with phakic and aphakic eyes.
• To determine the relationship between IOLs, AH composition, and corneal health.

Main Methods:

• Analysis of aqueous humor from five groups: cataract, posterior capsulotomy-IOL, Fuchs' endothelial dystrophy with corneal edema, aphakic bullous keratopathy, and pseudophakic bullous keratopathy.
• Quantification of total protein, total C3, and C3a cleavage products (activated C3).
• Statistical comparison of analyte levels across different ocular conditions.

Main Results:

• No significant difference in AH protein levels was found between pseudophakic, phakic, and aphakic eyes.
• C3a levels were not significantly different between pseudophakic and phakic eyes.
• Aphakic eyes showed significantly higher C3a levels than pseudophakic eyes.
• Eyes with corneal edema exhibited significantly higher levels of protein, C3, and C3a compared to eyes with clear corneas.

Conclusions:

• The study does not support the hypothesis that IOLs significantly alter AH protein and complement levels in vivo.
• Elevated AH protein, C3, and C3a levels are more strongly associated with corneal edema and dysfunctional corneal endothelium than with the presence of an IOL.
• The findings suggest that corneal pathology, rather than IOL presence, is a primary driver of complement system activation in the anterior chamber.