Panel A shows a vertical bar graph with Bb copy numbers on the y-axis and different tissues on the x-axis. The tissues include skin, tibiotarsus joints, quadriceps muscle, heart base, right inguinal lymph nodes, colon, pancreas, and mesenteric lymph nodes. Each bar represents the mean with error bars indicating standard error of the mean (SEM), and individual data points are shown as squares. Panel B contains histological images of the Mucosal-Associated Lymphoid Tissue (MALT) at day 14 and day 28 post-infection, with a line graph summarizing MALT height scores over time. The y-axis represents the MALT score, and the x-axis represents days post-infection. Panel C shows histological images of mononuclear (MN) cell infiltration at day 14 and day 28 post-infection, with a line graph summarizing MN severity scores over time. The y-axis represents MN severity, and the x-axis represents days post-infection. Panel D contains histological images of Paneth cell vacuolization and granulate size pleiomorphism at day 14 and day 28 post-infection, with line graphs summarizing Paneth cell granule pleio and vacuolization scores over time. The y-axes represent the respective scores, and the x-axes represent days post-infection. Panel E shows bar graphs of relative cytokine mRNA expression in small intestines at different days post-infection, assessed by qRT-PCR. The y-axes represent relative expression levels, and the x-axes represent days post-infection. Different cytokines (IL-10, IL-1 beta, IL-6, TNF) are depicted in separate bar graphs.
Bb colonization and early inflammatory responses in gut tissue of Bb-infected mice: C57BL/6 female mice were infected with Bb cN40 or sham-infected. (A) Bb copy numbers in skin, tibiotarsal joints (Tibio), quadriceps muscle (Quadr), heart base (HB), right inguinal lymph nodes (RLN), colon, pancreas, and mesenteric lymph nodes (mLN), as measured by Bb flagellin B PCR at 30 dpi. (B–D) Pathological evaluation of small intestines. Histological images were acquired at 40× magnification except the MALT, which were acquired at 4× magnification. The scale bar indicates 50 μm. (B) Left, MALT height (double-headed arrow); right, summary of results. (C) Left, mononuclear (MN) cell infiltration (arrowheads); right, summary of results. (D) Left, eosinophilic Paneth cell vacuolization and granulate size pleiomorphism (arrowheads); right, summary of results. (E) Relative cytokine mRNA expression in small intestines at indicated dpi, assessed by qRT-PCR. Statistical analyses were conducted using the Mann–Whitney U test. Bars indicate the mean ± SEM; each symbol represents one mouse (n = 3–6 per group). Each time point represents one independent experiment. **P ≤ 0.01, ***P ≤ 0.001, and ns, not significant (P > 0.05); NA, not available.