Separation of Bloodstream Trypomastigotes of Trypanosoma cruzi by Density Gradient Centrifugation

Mortatti, Rodnei C.; Munk, Martin E.

doi:10.2307/3281553

Cited by 7 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bloodstream trypomastigotes were obtained from Rockland mice at the peak of parasitemia (day 7). Trypomastigotes were purified as described previously [27], with some modifications. Purification was monitored by microscopy.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Inhibition of Early Endosome Fusion by Trypansom cruzi‐Infected Macrophage Cytosol

Ochatt

Mayorga

Isola

et al. 1997

J Eukaryotic Microbiology

View full text Add to dashboard Cite

Trypanosoma cruzi trypomastigotes survive inside macrophages by promoting fusion between the parasitophorous vacuole and mature host lysosomes upon internalization. Since trypomastigotes can evade the lytic pathway, the earliest steps of endocytosis, such as early endosome fusion, may be affected. To test this hypothesis, we used an in vitro early endosome fusion assay. Our results show that trypomastigote-infected macrophage cytosols cannot promote fusion between early endosomes, compared to mock-infected cytosols (heat-killed trypomastigotes were used in the parasite-macrophage interaction assay). GTP gamma S addition potentiates the fusogenic activity driven by trypomastigote-infected macrophage cytosol-mediated assays, unlike the biphasic fusogenic effect obtained with GTP gamma S treatment of macrophage cytosol controls. Calcium-stimulated early endosome fusogenic processes are not affected in the assays mediated by infected macrophage cytosol. We conclude that GTP-regulated factors, and not calcium-regulated elements, are involved in the inhibition of the early endosome fusogenic process by the trypomastigote-infected macrophage cytosol. This primary impediment to the progress of a normal endocytosis may be a relevant step required for the lysosomal recruitment-fusion of the host lysosomes upon trypomastigote infection and further survival of the parasite within its host.

show abstract

Section: Methodsmentioning

confidence: 99%

“…Heparinized infected blood (4 X lo7 trypomastigotes/ml blood) was centrifuged for 20 min at 100 X g to isolate parasites and blood cells. Modifications to the published protocol [27] were performed as follows. After centrifugation a fraction of the trypomastigotes still remained in the pellet.…”

Section: Methodsmentioning

confidence: 99%

Inhibition of Early Endosome Fusion by Trypansom cruzi‐Infected Macrophage Cytosol

Ochatt

Mayorga

Isola

et al. 1997

J Eukaryotic Microbiology

View full text Add to dashboard Cite

show abstract

“…Trypanosomes of the RA and K98 T. cruzi strains were purified from whole blood by density gradient centrifugation as described before (25). Trypomastigotes were subjected to five freeze-thawing cycles, resuspended in phosphatebuffered saline and sonicated (10 cycles of 30 s each at 40 Hz on ice).…”

Section: Mice Male C3h/henmentioning

confidence: 99%

Trypanosoma cruziInfection Modulates In Vivo Expression of Major Histocompatibility Complex Class II Molecules on Antigen-Presenting Cells and T-Cell Stimulatory Activity of Dendritic Cells in a Strain-Dependent Manner

et al. 2003

View full text Add to dashboard Cite

A striking feature of Chagas' disease is the diversity of clinical presentations. Such variability may be due to the heterogeneity among Trypanosoma cruzi isolates or to the host immune response. Employing two strains which differ in their virulence, we investigated the effect of in vivo infection on professional antigen-presenting cells (APC). Acute infection with the virulent RA strain downregulated the expression of major histocompatibility complex (MHC) class II on splenic dendritic cells (DC) and inhibited its induction on peritoneal macrophages and splenic B cells. It also impaired the ability of DC to prime allogeneic T cells and to form homotypic clusters, suggesting a low maturation state of these cells. In contrast, the low-virulence K98 strain maintained the expression of MHC class II on DC or stimulated it on peritoneal macrophages and B cells and preserved DC's T-cell priming capacity and homotypic clustering. DC from RA-infected mice elicited a lower activation of T. cruzi-specific T-cell proliferation than those from K98-infected mice. APC from RA-infected mice that reached the chronic phase of infection restored MHC class II levels to those found in K98-infected mice and upregulated costimulatory molecules expression, suggesting that the immunosuppression caused by this strain is only transient. Taken together, the results indicate that in vivo infection with T. cruzi modulates APC functionality and that this is accomplished in a strain-dependent manner.

show abstract

Fatty acid composition of amastigote and trypomastigote forms of Trypanosoma cruzi

et al. 1989

View full text Add to dashboard Cite

Separation of Bloodstream Trypomastigotes of Trypanosoma cruzi by Density Gradient Centrifugation

Cited by 7 publications

References 0 publications

Inhibition of Early Endosome Fusion by Trypansom cruzi‐Infected Macrophage Cytosol

Inhibition of Early Endosome Fusion by Trypansom cruzi‐Infected Macrophage Cytosol

Trypanosoma cruziInfection Modulates In Vivo Expression of Major Histocompatibility Complex Class II Molecules on Antigen-Presenting Cells and T-Cell Stimulatory Activity of Dendritic Cells in a Strain-Dependent Manner

Fatty acid composition of amastigote and trypomastigote forms of Trypanosoma cruzi

Contact Info

Product

Resources

About