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Erythrophagocytosis in Entamoeba histolytica and Entamoeba dispar: a comparative study.

Talamás-Lara D, Chávez-Munguía B, González-Robles A, Talamás-Rohana P, Salazar-Villatoro L, Durán-Díaz Á, Martínez-Palomo A - Biomed Res Int (2014)

Bottom Line: In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity.Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time.Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies, IPN, Avenida Instituto Politécnico Nacional No. 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, 07360 Mexico City, DF, Mexico.

ABSTRACT
Entamoeba histolytica is the causative agent of human intestinal and liver amebiasis. The extraordinary phagocytic activity of E. histolytica trophozoites has been accepted as one of the virulence mechanisms responsible for their invasive capacity. The recognition of the noninvasive Entamoeba dispar as a different species has raised the question as to whether the lack of pathogenic potential of this ameba correlates with a limited phagocytic capacity. We have therefore compared the process of erythrophagocytosis in both species by means of light and video microscopy, hemoglobin measurement, and the estimation of reactive oxygen species (ROS). In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity. We also observed by video microscopy a new event of erythrocyte opsonization-like in both species, being more characteristic in E. histolytica. Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time. Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

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Major nonphagocytic subpopulation of E. dispar versus a major phagocytic subpopulation of E. histolytica. Images taken from a video microscopy followup of the erythrocytes-trophozoites interaction showing the existence of a nonphagocytic subpopulation of E. dispar (most of the cells are nonphagocytic). Only a few cells contain erythrocytes (red dots) inside their cytoplasm even after 20 min interaction ((a)(A–I)). On the contrary, images taken from the video microscopy followup of E. histolytica trophozoites show that nearly 90% or higher of the population have ingested erythrocytes (red dots), after only 5 min of interaction ((b)(A–I)). Numbers shown in the upper right corner of each image correspond to time in seconds starting after 20 min incubation for E. dispar and 5 min incubation for E. histolytica.
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fig5: Major nonphagocytic subpopulation of E. dispar versus a major phagocytic subpopulation of E. histolytica. Images taken from a video microscopy followup of the erythrocytes-trophozoites interaction showing the existence of a nonphagocytic subpopulation of E. dispar (most of the cells are nonphagocytic). Only a few cells contain erythrocytes (red dots) inside their cytoplasm even after 20 min interaction ((a)(A–I)). On the contrary, images taken from the video microscopy followup of E. histolytica trophozoites show that nearly 90% or higher of the population have ingested erythrocytes (red dots), after only 5 min of interaction ((b)(A–I)). Numbers shown in the upper right corner of each image correspond to time in seconds starting after 20 min incubation for E. dispar and 5 min incubation for E. histolytica.

Mentions: Having evidence by video microscopy about the low adhesion capacity of E. dispar and observing that there were a notable number of nonphagocytic cells, we decided to determine the percentage of the nonphagocytic population for each species. Results showed that, after 20 to 30 min interaction of E. dispar with erythrocytes, (Figure 5(a)(A–I)) only a small number of amoebas with a limited number of internalized erythrocytes (red dots) were observed. In contrast, E. histolytica trophozoites, with only 5 min of interaction with erythrocytes (Figure 5(b)(A–I)) showed not only a large number of red blood cells in their cytoplasm (red dots) but also a very small number of amoebas that did not have ingested erythrocytes.


Erythrophagocytosis in Entamoeba histolytica and Entamoeba dispar: a comparative study.

Talamás-Lara D, Chávez-Munguía B, González-Robles A, Talamás-Rohana P, Salazar-Villatoro L, Durán-Díaz Á, Martínez-Palomo A - Biomed Res Int (2014)

Major nonphagocytic subpopulation of E. dispar versus a major phagocytic subpopulation of E. histolytica. Images taken from a video microscopy followup of the erythrocytes-trophozoites interaction showing the existence of a nonphagocytic subpopulation of E. dispar (most of the cells are nonphagocytic). Only a few cells contain erythrocytes (red dots) inside their cytoplasm even after 20 min interaction ((a)(A–I)). On the contrary, images taken from the video microscopy followup of E. histolytica trophozoites show that nearly 90% or higher of the population have ingested erythrocytes (red dots), after only 5 min of interaction ((b)(A–I)). Numbers shown in the upper right corner of each image correspond to time in seconds starting after 20 min incubation for E. dispar and 5 min incubation for E. histolytica.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4066688&req=5

fig5: Major nonphagocytic subpopulation of E. dispar versus a major phagocytic subpopulation of E. histolytica. Images taken from a video microscopy followup of the erythrocytes-trophozoites interaction showing the existence of a nonphagocytic subpopulation of E. dispar (most of the cells are nonphagocytic). Only a few cells contain erythrocytes (red dots) inside their cytoplasm even after 20 min interaction ((a)(A–I)). On the contrary, images taken from the video microscopy followup of E. histolytica trophozoites show that nearly 90% or higher of the population have ingested erythrocytes (red dots), after only 5 min of interaction ((b)(A–I)). Numbers shown in the upper right corner of each image correspond to time in seconds starting after 20 min incubation for E. dispar and 5 min incubation for E. histolytica.
Mentions: Having evidence by video microscopy about the low adhesion capacity of E. dispar and observing that there were a notable number of nonphagocytic cells, we decided to determine the percentage of the nonphagocytic population for each species. Results showed that, after 20 to 30 min interaction of E. dispar with erythrocytes, (Figure 5(a)(A–I)) only a small number of amoebas with a limited number of internalized erythrocytes (red dots) were observed. In contrast, E. histolytica trophozoites, with only 5 min of interaction with erythrocytes (Figure 5(b)(A–I)) showed not only a large number of red blood cells in their cytoplasm (red dots) but also a very small number of amoebas that did not have ingested erythrocytes.

Bottom Line: In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity.Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time.Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies, IPN, Avenida Instituto Politécnico Nacional No. 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, 07360 Mexico City, DF, Mexico.

ABSTRACT
Entamoeba histolytica is the causative agent of human intestinal and liver amebiasis. The extraordinary phagocytic activity of E. histolytica trophozoites has been accepted as one of the virulence mechanisms responsible for their invasive capacity. The recognition of the noninvasive Entamoeba dispar as a different species has raised the question as to whether the lack of pathogenic potential of this ameba correlates with a limited phagocytic capacity. We have therefore compared the process of erythrophagocytosis in both species by means of light and video microscopy, hemoglobin measurement, and the estimation of reactive oxygen species (ROS). In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity. We also observed by video microscopy a new event of erythrocyte opsonization-like in both species, being more characteristic in E. histolytica. Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time. Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

Show MeSH
Related in: MedlinePlus