The Physiological and Three–Dimensional Evaluation of Leukocyte Behavior in the Microcirculation of Mouse Retina

Abstract

Abstract: : Purpose: Leukocytes play a key role in inflammatory reactions. It is important to estimate the leukocyte behavior in the inflammatory tissue physiologically. It has been, however, difficult to monitor the leukocyte migration in the mouse retina in detail. This study was designed to establish the new methods to evaluate the leukocyte behavior in the mouse retina physiologically and three–dimensionally. Methods:Endotoxin–induced uveitis (EIU) was induced in mice by footpad injection of lipopolysaccharide (LPS). Leukocytes were labeled with acridine orange. Leukocyte rolling in the retinal microcirculation was evaluated in vivo with acridine orange digital fluorography. The number of the migrated leukocyte was counted in the flat–mounted retina. Leukocyte migration into the retina was monitored three–dimensionally with a confocal microscope and the velocity of the migration was calculated. Results:Leukocyte rolling and migration were both evaluated quantitatively and peaked at 48 hours after LPS injection. Leukocytes extravasated from the deeper capillary layers and traveled toward the outer layer of the retina. The velocity of leukocyte migration in the retina was 10 µm/hour. Conclusions:We have demonstrated the new methods to evaluate the leukocyte behavior in the mouse retina. With these methods, we are able to evaluate the activity of the leukocyte in retinal microcirculation of the mouse physiologically and quantitatively.

Keywords: inflammation • retina