Fig 1.
β-diversity in stool microflora in WT and Pglyrp-deficient mice.
(A) Principal Coordinate Analysis (PCoA) by UniFrac (unweighted) of microbiomes in WT and Pglyrp-deficient mice. Separation of stool microbiomes of WT mice from stool microbiomes of Pglyrp1-/- and Pglyrp3-/- mice (left panel), Pglyrp2-/- mice (middle panel), and Pglyrp4-/- mice (right panel). Each dot corresponds to a stool microbiome from one mouse. (B) Numbers of taxonomic units in Pglyrp-deficient mice with significantly (at P<0.05) increased or decreased abundance compared with WT mice; P, significance of the differences between the numbers of significantly increased and significantly decreased taxonomic units; groups with significantly more decreased than increased taxa are shaded in green, and groups with significantly more increased than decreased taxa are shaded in purple. N = 12 mice/strain. The % abundance of significantly changed microflora, P for abundance in Pglyrp-deficient versus WT microflora, and the ratio of abundance in Pglyrp-deficient to WT microflora for each strain and taxonomic unit are shown in S1–S6 Tables.
Fig 2.
β-diversity in bacterial classes in stool microflora of WT and Pglyrp-deficient mice.
Class abundance is expressed as % of total stool microflora. The classes with significantly different abundance in Pglyrp-deficient versus WT mice are marked with an asterisk (*) and listed as significantly (at P<0.05) increased or decreased (marked by upward or downward arrows); N = 12 mice/strain. The % abundance of significantly changed microflora, P for abundance in Pglyrp-deficient versus WT microflora, and the ratio of abundance in Pglyrp-deficient to WT microflora for each strain of mice are shown in S1 Table.
Fig 3.
Bacteria with significantly changed abundance in stools of Pglyrp-deficient mice.
Heatmap representation of the fold increase (red) or decrease (green) in the abundance of the indicated bacterial taxons, calculated as a ratio: % abundance in Pglyrp-deficient mice / % abundance in WT mice. The % abundance in WT mice is shown on the left of each heatmap panel. Taxons with no significant difference in abundance in any of the Pglyrp-deficient strains and low frequency taxons not detected in WT mice are omitted; * denotes species used in this study for colonizing mice. The % abundance of significantly changed microflora, P for abundance in Pglyrp-deficient versus WT microflora, and the ratio of abundance in Pglyrp-deficient to WT microflora for each strain and taxonomic unit are shown in S1–S6 Tables.
Fig 4.
Abundance of P. distasonis, P. falsenii, A. finegoldii, and B. eggerthii in WT and Pglyrp-deficient mice.
These species were selected for in vivo testing of their effect on susceptibility to colitis in Figs 5–8. The results are means ± SEM; N = 12 mice/strain; *, P<0.05; **, P<0.001 Pglyrp-deficient versus WT.
Fig 5.
P. falsenii, P. distasonis, and B. eggerthii, but not A. finegoldii, predispose mice depleted of intestinal microflora to colitis.
(A) WT mice were depleted of intestinal microflora by treatment with antibiotics and then gavaged every other day with P. falsenii, or P. distasonis, or B. eggerthii, or A. finegoldii, or stools from WT mice as a control, and also treated with DSS. (B) Mice were monitored over time for survival, change in body weight, and stool scores and rectal bleeding. (C) Gross rectal bleeding on day 10 in mice gavaged with P. falsenii, or P. distasonis, or B. eggerthii, but not in mice gavaged with A. finegoldii or stools from WT mice. (D) Representative hematoxylin-eosin stained sections from day 9 of the colons from mice gavaged with bacteria or WT stools or from untreated mice as indicated; BL, blood; EP, epithelial cells; LP, lamina propria; G, goblet cells; MM, muscularis mucosa; SM, submucosa; and IN, inflammatory cell infiltrations are indicated; size bar = 100 μm. (E) Severity of histopathological changes in the colon of mice gavaged with P. falsenii (Pf), or P. distasonis (Pd), or B. eggerthii (Be), or A. finegoldii (Af), or stools from WT mice and treated with DSS. The results are means ± SEM of 6 (in B) or 4 (in E) mice/group; significance of differences: *, P<0.05; **, P<0.001; as indicated (in B) or versus WT (in E); #, P<0.05 Af versus Pf, Pd, and Be (all P<0.001 for Af versus Pf and Be, except for hyperplasia).
Fig 6.
P. falsenii plus P. distasonis, and B. eggerthii plus A. finegoldii predispose mice depleted of intestinal microflora to colitis.
(A) WT mice were depleted of intestinal microflora by treatment with antibiotics and then gavaged every other day with P. falsenii plus P. distasonis, or B. eggerthii plus A. finegoldii, or with stools from WT mice as a control, and also treated with DSS. (B) Mice were monitored over time for survival, change in body weight, and stool scores and rectal bleeding. (C) Gross rectal bleeding on day 10 in mice gavaged with P. falsenii plus P. distasonis, or B. eggerthii plus A. finegoldii, but not in mice gavaged with stools from WT mice. (D) Representative hematoxylin-eosin stained sections from day 9 of the colons from mice gavaged with bacteria or WT stools as indicated; EP, epithelial cells; LP, lamina propria; G, goblet cells; MM, muscularis mucosa; SM, submucosa; and IN, inflammatory cell infiltrations are indicated; size bar = 100 μm. (E) Severity of histopathological changes in the colon of mice gavaged with P. falsenii plus P. distasonis (Pf + Pd), or B. eggerthii plus A. finegoldii (Be + Af), or stools from WT mice and treated with DSS. The results are means ± SEM of 6 (in B) or 4 (in E) mice/group; significance of differences: *, P<0.05; **, P<0.001; as indicated (in B) or versus WT (in E); #, P<0.05 Be + Af versus Pf + Pd.
Fig 7.
P. falsenii, P. distasonis, and B. eggerthii predispose WT mice with intact intestinal microflora to colitis, whereas A. finegoldii protects WT mice with intact intestinal microflora from colitis.
(A) WT mice were gavaged every other day with P. falsenii, or P. distasonis, or B. eggerthii, or A. finegoldii, or stools from WT mice as a control, and also treated with DSS. (B) Mice were monitored over time for survival, change in body weight, and stool scores and rectal bleeding. (C) Severe gross rectal bleeding on day 12 in mice gavaged with P. falsenii, or P. distasonis, or B. eggerthii, mild bleeding in mice gavaged with stools from WT mice, and not in mice gavaged with A. finegoldii. (D) Representative hematoxylin-eosin stained sections from day 11 of the colons from mice gavaged with bacteria or WT stools as indicated; BL, blood; EP, epithelial cells; LP, lamina propria; G, goblet cells; MM, muscularis mucosa; SM, submucosa; and IN, inflammatory cell infiltrations are indicated; size bar = 100 μm. (E) Severity of histopathological changes in the colon of mice gavaged with P. falsenii (Pf), or P. distasonis (Pd), or B. eggerthii (Be), or A. finegoldii (Af), or stools from WT mice and treated with DSS. (F) Abundance of DNA for the indicated bacteria in stools on day 9. The results are means ± SEM of 6 (in B and F) or 4 (in E) mice/group; significance of differences: *, P<0.05; **, P<0.001; as indicated (in B) or versus WT (in E and F); ##, P<0.001 Af versus Pf, Pd, and Be.
Fig 8.
P. falsenii plus P. distasonis, but not B. eggerthii plus A. finegoldii, predispose WT mice with intact intestinal microflora to colitis.
(A) WT mice were gavaged every other day with P. distasonis plus P. falsenii, or A. finegoldii plus B. eggerthii, or with stools from WT mice as a control, and also treated with DSS. (B) Mice were monitored over time for survival, change in body weight, and stool scores and rectal bleeding. (C) Severe gross rectal bleeding on day 12 in mice gavaged with P. falsenii plus P. distasonis, and mild bleeding in mice gavaged with B. eggerthii plus A. finegoldii, or with stools from WT mice. (D) Representative hematoxylin-eosin stained sections from day 11 of the colons from mice gavaged with bacteria or WT stools as indicated; BL, blood; EP, epithelial cells; LP, lamina propria; G, goblet cells; MM, muscularis mucosa; SM, submucosa; and IN, inflammatory cell infiltrations are indicated; size bar = 100 μm. (E) Severity of histopathological changes in the colon of mice gavaged with P. falsenii plus P. distasonis (Pf + Pd), or B. eggerthii plus A. finegoldii (Be + Af), or stools from WT mice and treated with DSS. (F) Abundance of DNA for the indicated bacteria in stools on day 9. The results are means ± SEM of 6 (in B and F) or 4 (in E) mice/group; significance of differences: *, P<0.05; **, P<0.001; as indicated (in B) or versus WT (in E and F); #, P<0.05; ##, P<0.001; Be + Af versus Pf + Pd.