TY - JOUR
T1 - Invasion of human retinal vascular endothelial cells by Toxoplasma gondii tachyzoites
AU - Zamora, D. O.
AU - Rosenbaum, J. T.
AU - Smith, J. R.
PY - 2008/6
Y1 - 2008/6
N2 - Background: Toxoplasma gondii infection is a leading cause of posterior uveitis. Human retinal endothelial cells (HREC) are more susceptible to infection with T gondii tachyzoites than other subpopulations of endothelial cells. It is hypothesised that this phenomenon reflects differences in invasion efficiency. Methods: YFP-expressing RH strain T gondii tachyzoites were added to confluent HREC or human dermal endothelial cells (HDEC) (MOI = 50:1). Tachyzoite invasion after 1 h was determined by microplate reading of fluorescence intensity or parasite counts obtained using image analysis software. Selected cultures were incubated for three subsequent days, at which time fluorescence intensity indicated intracellular tachyzoite proliferation. Results: HREC-tachyzoite cultures were more fluorescent than HDEC-tachyzoite cultures after 1 h (p = 0.020, paired t test, 3 experiments). Parasite counts also indicated that more tachyzoites invaded HREC than HDEC (p = 0.042, paired t test, 5 experiments). At 3 days, fluorescence intensity remained higher in HREC-tachyzoite cultures (p ≤ 0.002, t test, 3 experiments). Conclusion: In culture, T gondii tachyzoites invade HREC with greater efficiency than they invade HDEC. This observation suggests that the relative susceptibility of HREC to infection may reflect a high efficiency of tachyzoite invasion which may be relevant to understanding how T gondii infects human retina.
AB - Background: Toxoplasma gondii infection is a leading cause of posterior uveitis. Human retinal endothelial cells (HREC) are more susceptible to infection with T gondii tachyzoites than other subpopulations of endothelial cells. It is hypothesised that this phenomenon reflects differences in invasion efficiency. Methods: YFP-expressing RH strain T gondii tachyzoites were added to confluent HREC or human dermal endothelial cells (HDEC) (MOI = 50:1). Tachyzoite invasion after 1 h was determined by microplate reading of fluorescence intensity or parasite counts obtained using image analysis software. Selected cultures were incubated for three subsequent days, at which time fluorescence intensity indicated intracellular tachyzoite proliferation. Results: HREC-tachyzoite cultures were more fluorescent than HDEC-tachyzoite cultures after 1 h (p = 0.020, paired t test, 3 experiments). Parasite counts also indicated that more tachyzoites invaded HREC than HDEC (p = 0.042, paired t test, 5 experiments). At 3 days, fluorescence intensity remained higher in HREC-tachyzoite cultures (p ≤ 0.002, t test, 3 experiments). Conclusion: In culture, T gondii tachyzoites invade HREC with greater efficiency than they invade HDEC. This observation suggests that the relative susceptibility of HREC to infection may reflect a high efficiency of tachyzoite invasion which may be relevant to understanding how T gondii infects human retina.
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U2 - 10.1136/bjo.2007.133314
DO - 10.1136/bjo.2007.133314
M3 - Article
C2 - 18523089
AN - SCOPUS:45249110927
SN - 0007-1161
VL - 92
SP - 852
EP - 855
JO - British Journal of Ophthalmology
JF - British Journal of Ophthalmology
IS - 6
ER -