Figure 3. Defining the fungal microbiome and characterizing the specific role of Dectin-1-mediated host defense during colitis.

(A) DNA was isolated from murine feces and mycobiome analysis was performed using Roche 454 and Illumina GA sequencing of ITS1-2 rDNA. The taxonomic distribution of the most abundant fungal genera is shown (large pie chart), and species breakdown for major groups are provided (small pie charts). (B) Quantitative analysis of the major intestinal fungal genera in wild type and Clec7a^−/− mice before and after treatment with DSS. Illumina GA data were analyzed and presented as relative percentage of dominant fungal genera (n=16 mice). (C) Fungal invasion of colonic tissue in Clec7a^−/− mice during colitis. Colon sections from WT and Clec7a^−/− mice before and after colitis were stained with the sDEC-1 probe and counterstained with DAPI. (D) Intestinally conditioned dendritic cells were incubated with live C. tropicalis and killing was assessed after 6 and 18 hours. (E) Histology score of WT and Clec7a^−/− mice supplemented or not with four doses of C. tropicalis or S. fibuligera every other day, and then treated with 2.5% DSS for 7 days and kept on water for 4 additional days. Data are representative of at least two independent experiments with similar results. Error bars, s.d., * P < 0.05, ** P < 0.01.