Gut dysbiosis promotes the breakdown of oral tolerance mediated through dysfunction of mucosal dendritic cells

While dysbiosis in the gut is implicated in the impaired induction of oral tolerance generated in mesenteric lymph nodes (MesLNs), how dysbiosis affects this process remains unclear. Here, we describe that anti-biotic-driven gut dysbiosis causes the dysfunction of CD11c+CD103+ conventional dendritic cells (cDCs) in MesLNs, preventing the establishment of oral tolerance. Deficiency of CD11c+CD103+ cDCs abrogates the generation of regulatory T cells in MesLNs to establish oral tolerance. Antibiotic treatment triggers the intestinal dysbiosis linked to the impaired generation of colony-stimulating factor 2 (Csf2)-producing group 3 innate lymphoid cells (ILC3s) for regulating the tolerogenesis of CD11c+CD103+ cDCs and the reduced expression of tumor necrosis factor (TNF)-like ligand 1A (TL1A) on CD11c+CD103+ cDCs for generating Csf2-producing ILC3s. Thus, antibiotic-driven intestinal dysbiosis leads to the breakdown of crosstalk be-tween CD11c+CD103+ cDCs and ILC3s for maintaining the tolerogenesis of CD11c+CD103+ cDCs in MesLNs, responsible for the failed establishment of oral tolerance.

Automated summary

Dysbiosis in the gut impairs the induction of oral tolerance generated in MesLNs. Antibiotic-driven gut dysbiosis causes dysfunction of CD11c+CD103+ conventional dendritic cells (cDCs) in MesLNs, leading to the failure of establishing oral tolerance. This breakdown is caused by the impaired crosstalk between CD11c+CD103+ cDCs and ILC3s due to antibiotic-induced dysbiosis.