Article
NAD(P)H-oxidase presence in Toxoplasma gondii tachyzoite vacuole during interaction with IFN-gamma-activated human endothelial cells
Registro en:
CORTEZ, Erika et al. NAD(P) H-Oxidase presence in Toxoplasma Gondii Tachyzoite Vacuole during Interaction with IFN-Gamma_actiated human endothelial cells. Journal of Parasitology, v. 91, n. 5, p. 1053-1057, 2005.
0022-3395
10.1645/GE-467R1.1
1937-2345
Autor
Cortez, Erika
Stumbo, Ana Carolina
Carvalho, Técia Maria U, de
Barbosa, Helene Santos
Carvalho, Laís
Resumen
Toxoplasma gondii invades and proliferates in human umbilical vein endothelial cells (HUVEC) where it resides in a parasitophorous vacuole (PV) preventing lysosomal fusion. To study the intracellular outcome of PV containing tachyzoites of T. gondii during interaction with IFN-gamma-activated HUVEC, a quantitative analysis of the T. gondii infection and multiplication was assayed. The quantification of PVs' fusion with lysosomes, ultrastructural examination of phagosome-lysosome fusion, and the localization of NAD(P)H-oxidase activity were also investigated. HUVEC activated with IFN-gamma inhibited T. gondii infection and multiplication by 67.5% and 91.0%, respectively. After 4 hr of infection, 10.2% of IFN-gamma-activated HUVEC exhibited phagosome-lysosome fusion assayed by fluorescence microscopy, which was also observed at the ultrastructural level. Furthermore, the enzyme NAD(P)H-oxidase present at the plasma membrane of activated HUVEC was internalized together with the parasite in 38.0% of the cells. In addition, colocalization of colloidal gold particles and reaction product of NAD(P)H-oxidase in the PV of some activated HUVEC was observed. These results suggest that NAD(P)H-oxidase may participate in a mechanism by which IFN-gamma-activated HUVEC inhibit T. gondii multiplication. 2025-01-01