Experimental uveitis induced by intravitreal or intravenous lipoteichoic acid in rabbits.

Purpose: To investigate the role of lipoteichoic acid (LTA), one of the cell wall components in gram-positive bacteria in uveitis.
Methods: Intraocular inflammation in rabbit eyes was induced by intravitreal or intravenous injections of LTA from Staphylococcus aureus or Streptococcus sanguis. The inflammation was monitored progressively with the laser flare-cell photometer, and examined by periodic clinical observations. Histological examinations were performed 24 hours after administration, and aqueous protein concentrations and cell counts were also determined.
Results: Intraocular inflammation appeared within 6-9 hours of LTA intravitreal injection. became maximal at about 24-48 hours postinjection, and lasted for nearly 6 days. Intraocular inflammation was also induced by intravenous injection of LTA at a higher dose. Inflammation reached a peak 4-5 hours after injection, and rapidly disappeared in 24 hours. No cellular response was observed in intravenous LTA-treated eyes.
Conclusions: This study demonstrates that LTAs from gram-positive bacteria have the biological activity to induce intraocular inflammation in rabbits by intravitreal or intravenous injection. Therefore, we suggest that LTA may play a role in the pathogenesis of uveitis as one of the etiological factors.