Ocular toxoplasmosis: the role of cellular immune defense in the development of recurrences. Results from animal experiments.
Five toxoplasmosis-free animals and ten animals that had been immunized intraocularly against toxoplasma organisms were used in a rabbit model of ocular toxoplasmosis. Five of the ten immune animals were immunosuppressed by cyclosporin A at a cellular level. Experimental toxoplasmic retinochoroiditis occurred in all animals, a process that in complete contradiction to experience reported previously. In the rabbit model, immunity after a past history of toxoplasma infection has thus far appeared to be a safe form of protection from experimental ocular toxoplasmosis. The concept of "immunological privilege of the eye" is discussed as the cause for the unexpected results.
Friedrich
R
R
Department of Ophthalmology, Friedrich-Schiller University, Jena, Federal Republic of Germany.
Simon
H U
HU
Müller
W A
WA
Sych
F J
FJ
D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology; D002825:Chorioretinitis / Q000276:immunology / Q000469:parasitology; D016572:Cyclosporine / Q000008:administration & dosage; D004195:Disease Models, Animal; D005260:Female; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D010835:Phytohemagglutinins / Q000276:immunology; D011817:Rabbits; D012008:Recurrence; D014122:Toxoplasma / Q000276:immunology; D014126:Toxoplasmosis, Ocular / Q000276:immunology* / Q000517:prevention & control
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D010835:Phytohemagglutinins; D016572:Cyclosporine