Fig. 3

Defective oral tolerance in γδ^−/− mice is mediated by the gut microbiota. a Microbiota was depleted with a combination of 4 antibiotics (ABX) in the drinking water for 3 days and 1 day later, microbiota from WT and γδ^−/− mice were swapped. To assess oral tolerance, 3 days later, half of each group were fed OVA in the drinking water for 5 days. OVA continuous feeding was stopped and 2 days later mice were immunized with OVA/CFA. In an independent cohort, the immune responses were characterized 17 days post colonization. b Oral tolerance to OVA was measured by splenocyte proliferation upon 100 µg/mL of OVA stimulation. Data are mean + SEM; n=5 mice/group; one-way ANOVA. c–e FACS plots and bar graphs showing frequencies of live CD3⁺CD4⁺Foxp3⁺ (c) CD3⁺CD4⁺IL-17A⁺ (d) in the small intestine lamina propria (SILP), and migratory cDC1s (MHC-II^highCD11c⁺CD11b⁻CD103⁺XCR1⁺Sirpα⁻) and cDC2s (MHC-II^highCD11c⁺CD11b⁺CD103⁺XCR1⁻Sirpα⁺) (e) from the mesenteric lymph node (mLN) of mice colonized with WT or γδ^−/− microbiota. (f) FACS plots and bar graphs showing frequencies of live CD11b⁺CD103⁻CX3CR1⁺IL-10⁺ mononuclear phagocytes (MNPs) in the SILP of IL-10-GFP reporter mice treated with broad-spectrum antibiotics or left untreated (for mice treated with PBS) for 3 days and colonized 2 days later with WT or γδ^−/− microbiota or treated with PBS. Data are mean ± SEM; n=5–8 mice/group; one-way ANOVA. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001. Results are representative of at least two independent experiments