December 1993
Volume 34, Issue 13
Free
Articles  |   December 1993
A feline model of ocular toxoplasmosis.
Author Affiliations
  • M G Davidson
    Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
  • M R Lappin
    Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
  • R V English
    Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
  • M B Tompkins
    Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
Investigative Ophthalmology & Visual Science December 1993, Vol.34, 3653-3660. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      M G Davidson, M R Lappin, R V English, M B Tompkins; A feline model of ocular toxoplasmosis.. Invest. Ophthalmol. Vis. Sci. 1993;34(13):3653-3660.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
This content is PDF only. Please click on the PDF icon to access.
Abstract

PURPOSE. This study was performed to characterize the clinical, serologic, histopathologic, and immunohistochemical features of an experimental model of ocular toxoplasmosis in cats. METHODS: Seven specific pathogen-free cats were inoculated in the right carotid artery with 5 x 10(3) tachyzoites of the ME49 strain of Toxoplasma gondii. Control cats received heat-killed tachyzoites. RESULTS: Progressive, bilateral, multifocal retinal, and choroidal inflammatory foci developed in the principal cats, beginning 5 to 8 days postinoculation (PI). Lesion development peaked 3 weeks PI, and the lesions varied in size from pinpoint to 5 mm, had a predilection for the central tapetal fundus, and were more numerous ipsilateral to the side of inoculation. Resolution of the lesions 21 to 70 days PI was characterized by foci of tapetal destruction and retinal degeneration. Fluorescein angiography showed disruption of the blood-retinal barrier at the level of the retinal pigmented epithelium, and occasional retinal vasculitis and perivasculitis. Mild anterior uveitis developed in four cats 10 to 13 days PI. Aside from a slight febrile response 2 to 3 days PI, no physical abnormalities were observed. T. gondii antigens were detected intermittently in the serum of four of seven cats as early as 8 days PI. T. gondii-specific immunoglobulin M titers were present on day 7 PI and continued to increase until 28 days PI. Immunoglobulin G production was documented on day 13 PI, and titers continued to increase throughout the study. Evidence of anterior uveal antibody production (mean Goldmann-Witmer coefficient [C value], 80.7; range, 13.4 to 236.6) was present in 11 of 14 eyes on day 70 PI. On histopathologic evaluation 70 days PI, multifocal granulomatous chorioretinitis, with retinal degeneration, retinal vasculitis, and lymphocytic-plasmacytic anterior uveitis, was documented. Tissue cysts in the retina and choroid were found with mouse inoculation of tissue suspensions, immunohistochemical studies, and histopathologic examination. CONCLUSIONS: This nonfatal, noninvasive method of inducing ocular toxoplasmosis may prove to be a useful model for investigation of toxoplasmi retinochoroiditis, particularly with the recent characterization of a naturally occurring, immunosuppressive feline lentivirus with properties similar to human immunodeficiency virus.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×