Figure 7. Effects of dysbiotic microbiota of mdx on intestine, spleen and muscle inflammation and muscle function.

• A
  FACS analysis of T cell subsets from lamina propria in 3m C57Bl (n = 5), mdx (n = 5), and ABX‐mdx^FMT_C57Bl (n = 5/6) showing decrease in CD3⁺ T cells in ABX‐mdx^FMT_C57Bl. Infiltrating CD3⁺CD4⁺, and regulatory CD69⁺ subsets of CD4⁺ and CD8⁺ were decreased in ABX‐mdx^FMT_C57Bl. Eubiotic FMT in mdx modulates T helper response, with reductions in the cumulative frequencies of CD4⁺ IFNγ⁺ (Th1) and CD4⁺ IL‐10⁺ cells in ABX‐mdx^FMT_C57Bl. Data are presented as mean ± SD (*P < 0.05; **P < 0.01 ordinary one‐way ANOVA, Tukey's multiple‐comparison test).
• B
  FACS analysis of spleen and muscle homogenates from 3m C57Bl (n = 5), mdx (n = 5), and ABX‐mdx^FMT_C57Bl (n = 5/6). Analysis of the spleen revealed downregulation of Ly6C⁺ inflammatory monocytes and F4/80⁺ macrophages in ABX‐mdx^FMT_C57Bl. Eubiotic FMT in mdx mice determined a decrease of CD4⁺/CD8⁺ CD44⁺CD62L effector and GITR⁺CD4⁺ T‐cells in ABX‐mdx^FMT_C57Bl. Gut‐derived CCR9⁺CD8⁺TEM⁺ cells were increased in ABX‐mdx^FMT_C57Bl. Data are presented as mean ± SD (*P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001, ordinary one‐way ANOVA, Tukey's multiple‐comparison test).
• C
  Graphs showing cumulative frequencies of infiltrating CD45⁺CD4⁺ and CD45⁺CD8⁺ cells in muscles of 3m C57Bl (n = 5), mdx (n = 5) and ABX‐mdx^FMT_C57Bl (n = 5/6) were decreased in ABX‐mdx^FMT_C57Bl related to mdx mice. Data are presented as mean ± SD (*P < 0.05; **P < 0.01, ordinary one‐way ANOVA, Tukey's multiple‐comparison test).
• D, E
  Representative H&E staining (D) and quantification of myofiber area with Image J software (E) of TA muscles from 3m C57Bl (n = 5), mdx (n = 5) and ABX‐mdx^FMT_C57Bl (n = 6). Scale bars for H&E: 200 μm.
• F
  Measurement of ALT, and CPK in the serum of 3m C57Bl (n = 5), mdx (n = 5), and ABX‐mdx^FMT_C57Bl (n = 6).
• G
  Tetanic force of TA muscles from mdx (n = 5) and ABX‐mdx^FMT_C57Bl (n = 6).
• H
  Representative images of skeletal muscle showed the distribution and composition of MyHC isoforms (Type IIa, Type IIx, and Type IIb). Scale bar: 50 μm.
• I
  Graph portrays the percentage of myofibers expressing different MyHC isoforms. n = 12 images were analyzed for each mouse.
• J, K
  Representative SDH staining and quantification of percentage of SDH⁺ myofibers of TA muscles from mdx (n = 5) and ABX‐mdx^FMT_C57Bl (n = 6) (n = 12 images per mouse). Scale bar: 200 μm.
• L, M
  Representative image of CD31 (in cyan), α‐SMA (in green), and isolectin (in red) staining and their quantification in TA muscles from mdx (n = 5) and ABX‐mdx^FMT_C57Bl (n = 6) mice. Scale bar: 500 μm.

Data information: Data for tetanic force, ALT and CPK concentration, and staining quantification are presented as mean ± SD (*P < 0.05, **P < 0.01, ***P < 0.001; ****P < 0.0001, one‐way ANOVA, Tukey's multiple‐comparison test).

Source data are available online for this figure.