产B BALANC isotype CD20 gA: RAG iso. CD20 05101520250 days after cohousing G 32 H colon mucus ileum ● colon lumen▲ ileum lumen colon mucus a ileum mucus ≡lA =02 Fig. 4. Iga production in vivo is necessary for single-strain stability, mucosal colonization, and epithelial aggregation (A)IgA coating of wild-type B. fragilis in feces following injection of anti-CD20 or isotype control antibody (unpaired t test, n=8).(B)Epithelial cell adherence assay of wild-type B fragilis incubated with IgA extracted from indicated mono-colonized mice(Tukey ANOVA n= 4 mice as the source of bacteria). (C)Abundance of foreign strains exchanged between pairs of wild-type B. fragilis mono-colonized mice treated with anti-CD20 or an isotype control(Sidak repeated measure 2-way ANOVA on log-transformed data, n= 10). (D) Foreign strains exchanged between pairs of BALB/c and BALB/c IgA/ -mice mono- colonized with wild-type B. fragilis(Sidak repeated measure 2-way ANOVA on log transformed data, n=9).(E)CFU plating of ascending colon mucus of wild-type and IgA- mice mono-colonized with wild-type B. fragilis (unpaired t test, n=9).(F) Representative TEM projections of ascending colon(yellow arrow: epithelial cell) from mice mono- colonized with wild-type B. fragilis(green arrow)(n=3 mice per group, about 1 mm epithelium scanned per mouse)and(G)quantification of bacterial cells per projection montage(unpaired t test, n=7, 6 images from 3 mice per group)(H) Principle coordinate analyses of weighed UniFrac distances of 16S community profiles of ex-germ-free BALB/c and BALB/c IgA- mice transplanted with a complex mouse microbiota(Adonis test within colon for lumen/mucus difference). (D) Relative abundance of B. fragilis and highly IgA- coated ES Vs in ex-germ-free mice( p<0.05,*p<0.01,**p<0.001) cience. Author manuscript; available in PMC 2018 November 18Fig. 4. IgA production in vivo is necessary for single-strain stability, mucosal colonization, and epithelial aggregation (A) IgA coating of wild-type B. fragilis in feces following injection of anti-CD20 or isotype control antibody (unpaired t test, n = 8). (B) Epithelial cell adherence assay of wild-type B. fragilis incubated with IgA extracted from indicated mono-colonized mice (Tukey ANOVA, n = 4 mice as the source of bacteria). (C) Abundance of foreign strains exchanged between pairs of wild-type B. fragilis mono-colonized mice treated with anti-CD20 or an isotype control (Sidak repeated measure 2-way ANOVA on log-transformed data, n = 10). (D) Foreign strains exchanged between pairs of BALB/c and BALB/c IgA−/− mice mono￾colonized with wild-type B. fragilis (Sidak repeated measure 2-way ANOVA on log￾transformed data, n = 9). (E) CFU plating of ascending colon mucus of wild-type and IgA−/− mice mono-colonized with wild-type B. fragilis (unpaired t test, n = 9). (F) Representative TEM projections of ascending colon (yellow arrow: epithelial cell) from mice mono￾colonized with wild-type B. fragilis (green arrow) (n = 3 mice per group, about 1 mm epithelium scanned per mouse) and (G) quantification of bacterial cells per projection montage (unpaired t test, n = 7, 6 images from 3 mice per group) (H) Principle coordinate analyses of weighed UniFrac distances of 16S community profiles of ex-germ-free BALB/c and BALB/c IgA−/− mice transplanted with a complex mouse microbiota (Adonis test within colon for lumen/mucus difference). (I) Relative abundance of B. fragilis and highly IgA￾coated ESVs in ex-germ-free mice (* p < 0.05, ** p < 0.01, *** p < 0.001). Donaldson et al. Page 13 Science. Author manuscript; available in PMC 2018 November 18. Author Manuscript Author Manuscript Author Manuscript Author Manuscript