The effect of IFN-γ and TGF-β in the functional activity of mononuclear cells in the presence of Entamoeba histolytica

Moraes LC, França EL, Pessoa RS, Fagundes DL, Hernandes MG, Ribeiro VP, Gomes MA, Honorio-França AC Parasites & Vectors (2015) 8:413

Speaker: Sina Taheri Baghmisheh (白明旭)                                   )            Time: 15:00~16:00, Mar. 9, 2016

Commentator: Dr. Wei-Chen Lin (林威辰 老師)                        )    Place: Room 601

Abstract:

                Amoebiasis is considered the second leading cause of death worldwide due to parasitic diseases, causing approximately 40 to 100 000 deaths per year [1]. Entamoeba histolytica (E. histolytica) infections are usually asymptomatic, but in approximately 10 % of cases, the trophozoites penetrate the gut tissue, initiate hemorrhagic colitis and induce amoebic liver abscess [2]. Phagocytic cells and cytokines appear to be important in amoebiasis also E. histolytica is capable of inhibiting the production of active oxygen metabolites by monocytes [3], which probably prevent the death of the parasite during leukophagocytosis. In this study cytokines have been shown to be able to regulate monocyte function and increase the amoebicidal activity of monocytes [4]. The aim of this study was to analyze the supernatant of cultures of mononuclear (MN) cells with E. histolytica to determine: 1) the levels of the cytokines IFN-γ and TGF-β, and 2) the amoebicidal activity of MN cells after incubation with cytokines. In the presence of IFN- γ or TGF- β, a lower ingestion of MN cells was observed by amoebae and MN cells treated with cytokines exhibited higheramoebicide and apoptosis indexes. These results suggest that cytokines play a beneficial role for the host by activating MN cells against E. histolytica. The increased death of amoebae during the leukophagocytosis suggests that both cytokines (IFN-γ and TGF-β) can modulate the functional activity of MN cells and that these cytokines probably are important in the control of amoebic infections.

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