Fig. 4

Colonization and cecal inflammation by WT, SEN ∆alr, SEN ∆dadX, SEN ∆3897 and SEN ∆alr∆dadX of S. Enteritidis in C57BL/6 mice. a–d Streptomycin-pretreated mice were infected with the above strains, sacrificed 72 h p.i. and bacterial loads in mesenteric lymph node (mLN), spleen, liver and cecum were determined. e–i Histopathological assessment of the cecal tissue from animals infected with WT, SEN ∆alr, SEN ∆dadX and SEN ∆3897 and SEN ∆alr∆dadX. j Cecal pathological analysis by semiquantitative method. Bars, 100 µm. S submucosa, L lumen, LP lamina propria. Statistical significance: *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001