Figure 4. Translocated microbiota in the intestinal epithelium following L. interrogans infection.

Six-week-old female hamsters were injected intraperitoneally with 10⁷ leptospires. Hamsters were euthanized at 0 d, 2 d, and AM post infection (p.i.). Colons were collected aseptically. The intestinal contents were excluded from the intestine with phosphate-buffered saline (PBS) and a segment of the colon was fixed in 4% paraformaldehyde solution overnight and analyzed by fluorescence in situ hybridization (FISH) with an EUB 338 probe (red). (A) The results are representative photographs of three groups. Scale bar, 100 μm. (B) Number of positive bacteria per field in the three groups. n = 6 per group. D0, uninfected hamster; AM, articulo mortis. Each infection experiment was repeated three times. Data are shown as the mean ± SEM and analyzed by using the Wilcoxon rank-sum test. ***p<0.001.

Figure 4—figure supplement 1. Translocation of the Proteobacteria during L. interrogans infection.

Six-week-old female hamsters were intraperitoneally infected with 10⁷ leptospires. Colons of the D0 group and the AM group were collected and detected by fluorescence in situ hybridization (FISH) and immunofluorescence (IF). Blood from the D0 group and the AM group was plated on LB agar or MacConkey agar plates aerobically or anaerobically at 37°C for 36 hr. D0, uninfected hamster; AM, articulo mortis. (A) Colons of D0 (n = 4) and AM (n = 4) were examined by FISH with GAM42a probe (red) and by IF with anti-Leptospira serum (green). Scale bar, 20 μm. (B, C) The blood of the D0 (n = 4) hamsters and AM hamsters (n = 4) was aerobically or anaerobically cultured on LB plates (B) or MacConkey plates (C). Each experiment was repeated three times.