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

Abstract

BackgroundEntamoeba histolytica (E. histolytica) causes amoebiasis, which is a disease with significant morbidity and mortality. Phagocytic cells and cytokines appear to be important in amoebiasis, but very little is known about the influence of these cells and cytokines in protozoan infections. The aim of this study was to analyse 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.MethodsBlood samples were collected from 30 volunteer donors. The cytokine concentrations in MN cells culture supernatants, superoxide release, leukophagocytosis, amoebicide activity, intracellular calcium release and apoptosis were analysed.ResultsThe IFN-γ concentrations were 6.22 ± 0.36 and TGF-β concentrations were 17.01 ± 2.21 in cells–trophozoite culture supernatants. MN cells, independently of cytokines, in the presence of amoeba increase the superoxide release. In the absence of cytokines, the ingestion of MN cells by amoebae was higher. In the presence of IFN- γ or TGF- β, a lower ingestion of MN cells was observed by amoebae. MN cells treated with cytokines exhibited higher amoebicide and apoptosis indexes. The incubation of cytokines increased the intracellular calcium release by MN cells.ConclusionsThese 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.

Entamoeba histolytica Calreticulin Induces the Expression of Cytokines in Peripheral Blood Mononuclear Cells Isolated From Patients With Amebic Liver Abscess

“…In addition, Meza et al ( 2014 ) demonstrated that virgin T-cell differentiation into Th17 cells producing IL-17 occurred after the direct stimulation with other cytokines such as TGFβ, IL-6, and IL-1 in a murine model of infection with Trypanosoma cruzi . Moraes et al ( 2015 ) reported that mononuclear cells collected from healthy individuals incubated with E. histolytica in culture induced the production of IFN γ and TGFβ, and that both had a beneficial effect on the modulation of the activity of these cells. Our results agree with data of Moraes regarding the effects on IFNγ.…”

Entamoeba histolytica induces human neutrophils to form NETs

“…In vitro, leucocytes activated by TGF-b and IFN-c diminish E. histolytica viability by 10%. (15). On the other hand, in vitro studies demonstrated that contact with myeloperoxidase and hydrogen peroxide reduced E. histolytica viability by 90% (16).…”

Characteristics of inflammatory reactions during development of liver abscess in hamsters inoculated with Entamoeba nuttalli

“…These cytokines, the levels of which correlate with the degree of tissue damage, are released by attacked host cells or effector cells. IFN-γ is a suppressive cytokine that can clear the parasite [ 45 ]. In the present study, there was no significant increase in IFN-γ during ALA development in hamsters, perhaps suggesting that persistent progression of lesions facilitates invasive amebiasis.…”