IL10, TGF Beta1, and IFN Gamma Modulate Intracellular Signaling Pathways and Cytokine Production to Control Toxoplasma gondii Infection in BeWo Trophoblast Cells1

Abstract

Considering that interleukin 10 (IL10), transforming growth factor beta1 (TGFB1), and interferon gamma (IFNG) are involved in the susceptibility of BeWo trophoblast cells to Toxoplasma gondii infection, the aim of the present study was to investigate the effector mechanisms triggered by these cytokines in the control of T. gondii in BeWo cells. For this purpose, infected/uninfected BeWo cells were treated with IL10, TGFB1 (50 ng/ml), and IFNG (20 or 100 ng/ml) in order to verify the phosphorylation of signal transducers and activators of transcription 1 (STAT1), STAT3, and Smad2, parasite intracellular proliferation, as well as the Th1/Th2/IL17A cytokine production. The treatment of BeWo cells with IL10 and TGFB1 favored T. gondii proliferation, and these findings were associated with STAT3 and Smad2 phosphorylation, respectively (P < 0.05). Also, these cytokine treatments were able to down-modulate TNF alpha (TNFA) and IL6 production (P < 0.05). Low concentration of IFNG was unable to control T. gondii infection but was able to trigger STAT1 phosphorylation and up-regulate IL6 and IL17A production; whereas a high concentration of IFNG was unable to activate STAT1 but down-modulated IL6 and TNFA and increased T. gondii proliferation (P < 0.05). IL10, TGFB1, and IFNG regulate a differential T. gondii proliferation in BeWo cells because they distinctly trigger intracellular signaling pathways and cytokine production, especially IL6 and TNFA. Our data open new windows to understand the mechanisms triggered by IL10, TGFB1, and IFNG at the maternal-fetal interface in the presence of T. gondii, contributing to recognizing the importance of these effector mechanisms involved in the vertical transmission of this parasite.

Enrofloxacin and Toltrazuril Are Able to Reduce Toxoplasma gondii Growth in Human BeWo Trophoblastic Cells and Villous Explants from Human Third Trimester Pregnancy

“…Furthermore, we previously showed that BeWo cells treated with MIF or IL-6 recombinant cytokines significantly reduced the T. gondii proliferation, evidencing the important role of these mediators in the control of infection during a pregnancy (Barbosa et al, 2014, 2015). Then, the upregulation of these cytokines can be a mechanism triggered by the host cells, as trophoblast cells, to control the T. gondii infection.…”

“…In parallel, T. gondii tachyzoites from ME49 strain (moderate virulence) were provided from Dr. Karine Resende, Federal University of Triângulo Mineiro, MG, Brazil. Both parasite strains were maintained in culture flasks containing BeWo cells in RPMI 1640 medium supplemented with penicillin, streptomycin and 2% FBS at 37°C and 5% CO 2 (Angeloni et al, 2013; Barbosa et al, 2015). …”

“…Our previous studies demonstrated that BeWo cells and villous explants infected by T. gondii release MIF and IL-6 (de Oliveira Gomes et al, 2011; Franco et al, 2011; Barbosa et al, 2015). Furthermore, we previously showed that BeWo cells treated with MIF or IL-6 recombinant cytokines significantly reduced the T. gondii proliferation, evidencing the important role of these mediators in the control of infection during a pregnancy (Barbosa et al, 2014, 2015).…”

“…Our group has investigated several aspects of immumodulation mechanisms at the maternal-interface using BeWo cells as a trophoblast model, including their cross-talk with monocytes (Castro et al, 2013) and the role of cytokines and drugs during T. gondii infection (Franco et al, 2011; Barbosa et al, 2014, 2015). Even though BeWo cells are derived from a human choriocarcinoma, they are becoming an excellent in vitro model to investigate T. gondii infection in trophoblast cells (Franco et al, 2011; Castro et al, 2013; Barbosa et al, 2014, 2015), since they conserve many characteristics of the normal human trophoblast cells, such as the trophoblast/epithelial marker CK7 (Abou-Kheir et al, 2017), and cytokine and hormone production (Pattillo and Gey, 1968).…”

“…Even though BeWo cells are derived from a human choriocarcinoma, they are becoming an excellent in vitro model to investigate T. gondii infection in trophoblast cells (Franco et al, 2011; Castro et al, 2013; Barbosa et al, 2014, 2015), since they conserve many characteristics of the normal human trophoblast cells, such as the trophoblast/epithelial marker CK7 (Abou-Kheir et al, 2017), and cytokine and hormone production (Pattillo and Gey, 1968). In addition, our group has been investigating the T. gondii infection in human villous explants from the first and third trimester as an experimental model of the maternal-fetal interface (de Oliveira Gomes et al, 2011; Castro-Filice et al, 2014).…”