The lectin-specific activity ofToxoplasma gondiimicroneme proteins 1 and 4 binds Toll-like receptor 2 and 4 N-glycans to regulate innate immune priming

Abstract

32The infection of the host cell with Toxoplasma gondii involves the regulated 33 secretion of microneme proteins (TgMICs)

Toxoplasma and Dendritic Cells: An Intimate Relationship That Deserves Further Scrutiny

“…However, the responses of splenic DCs isolated from infected mice or of splenic DCs infected ex vivo with live parasites have not been explored in this study. Along this line, parasite surface adhesins TgMIC1/MIC4 were recently reported to stimulate IL-12 secretion in a TLR2-dependent manner in bone marrow-derived DCs (BMDCs) [20] (Figure 3b). Alterations in the production of additional TLR2-stimulated cytokines, notably type I interferons (IFN-I) [21], or in the regulation of other DCs functions (e.g.…”

The UPR sensor IRE1α promotes dendritic cell responses to control Toxoplasma gondii infection

“…UPR activation and downstream cytokine responses in DCs and macrophages were demonstrated to be under the control of PRR signaling (Martinon et al , 2010; Smith, 2018). Despite the established role of TLR11/12 in parasite detection in infected mice (Andrade et al , 2013; Koblanski et al, 2013; Hou et al , 2011; Yarovisnki et al, 2005), the innate sensing mechanisms of parasites residing into a intracellular vacuole are not fully elucidated (Poncet et al , 2019) and presumably involve distinct signals depending on early parasite attachment to host cells and subsequent partial vacuolar lysis leading to antigen escape into the host cytosol (Fisch et al , 2020; Kongsomboonvech et al , 2020; Sardhina‐Silva et al, 2019; Lee et al , 2015). Thus, to establish the role of innate sensing in UPR activation, we used BMDCs differentiated from mice lacking the adaptor MyD88 (MyD88KO mice) (Deguine & Barton, 2014).…”