Apoptosis within mouse eye induced by Toxoplasma gondii.
OBJECTIVE
To investigate apoptosis induced by Toxoplasma gondii (T. gondii) in eyes of C57BL/6 (B6) mice.


METHODS
Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) technique and pathological changes within eyes were analyzed at different time points after intraocular inoculation of either 50 or 500 of tachyzoites.


RESULTS
In eyes that received 50 tachyzoites, a few apoptotic inflammatory cells in the anterior chamber and keratocytes in the cornea were seen at days 1 and 2, but no apoptosis was detected 4 days after inoculation. Significantly greater apoptosis of inflammatory cells was observed in the anterior chamber and in the vitreous of eyes injected with 500 parasites. Apoptosis of inflammatory cells in the anterior chamber and of keratocytes in the cornea was seen at day 1. The apoptotic stromal keratocytes strikingly increased at day 4. There were a number of apoptotic inflammatory cells in the vitreous at day 2, and a few apoptotic retinal cells along the internal limiting membrane and the nerve fiber layer of the retina 4 days after inoculation.


CONCLUSIONS
These results suggest that apoptosis of inflammatory cells infiltrated eye infected with this parasite may be a mechanism of eliminating the organism.
Hu
S
S
Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China. markhu@gzsums.edu.cn
Schwartzman
J D
JD
Kasper
L H
LH
D000818:Animals; D000867:Anterior Chamber / Q000469:parasitology / Q000473:pathology; D017209:Apoptosis; D003315:Cornea / Q000469:parasitology / Q000473:pathology; D005123:Eye / Q000469:parasitology* / Q000473:pathology; D005260:Female; D020287:In Situ Nick-End Labeling; D051379:Mice; D008810:Mice, Inbred C57BL; D014122:Toxoplasma / Q000254:growth & development*; D014124:Toxoplasmosis, Animal / Q000469:parasitology* / Q000473:pathology