Abstract
Purpose :
To develop an experimental model of chronic uveitis in rabbit.
Methods :
Uveitis was induced in New Zealand albino rabbits by intravitreal injection of Mycobacterium tuberculosis antigen (first challenge) in preimmunized animals. Induction was followed by an intravitreal injection of triamcinolone acetonide (TAA), 2 mg, or saline solution. A second intravitreal challenge was performed in both groups two weeks after the first challenge. Clinical signs of uveitis in anterior chamber and vitreous were scored by slit lamp observation twice a week after the challenges, then weekly for 2 months. Histopathology was performed as final end-point.
Results :
Clinicals signs of uveitis were observed in two days after the first intravitreal challenge. Slit lamp examination revealed inflammatory state in the anterior chamber, cells infiltration, iritis, and haze in the vitreous. The maximum response was obtained within three days after the challenge. Then the inflammatory signs gradually decreased until the second challenge that induced a stronger and more sustained inflammatory response. TAA treatment significantly reduced inflammation all along the study. Histological analysis indicated signs of panuveitis in the saline solution treated animals: inflammation of the iris and ciliary body with exudate in aqueous humor, degenerative vitreous with fibrous material and inflammatory cells, cells infiltration in the retina and in the optic nerve head and some retinal detachment or disorganization of retinal layers. TAA treated animals showed less cells infiltration and a preserved retina.
Conclusions :
Here was presented an experimental model of chronic uveitis in rabbit where a single administration of TAA reduced inflammation. This rabbit model of chronic uveitis can be used to test efficacy of long-term treatment and delivery devices, due to the appropriate size of rabbit eye.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.