Analysis of bacterial growth in these mice serves as an excellent model for comparing the virulence of different bacterial strains and mutants and for studying how they cause opportunistic infections in immunocompromised hosts. Mice were inoculated intraperitoneally to assess the ability of the bacteria to cause systemic infection. Mice were also infected intragastrically, a natural route
of infection. To study the virulence of the tagged strains, the survival rates of the infected animals were determined. When intragastrically infected with 5 × 106CFU of the tagged or the wild type strains, all BALB/c mice died within 9 days postJSH-23 order infection (Figure1B). When SCID mice were infected intragastrically NCT-501 ic50 with selleck products 1 × 103CFU bacteria, all animals died within 8 days postinfection
(Figure1C). In either strain of mice, no difference was observed between the wild type and tagged strains (Figure1B–C), suggesting that epitope tagging of the SPI-1 proteins did not affect the virulence of theSalmonellastrains. Similar results were also observed when animals were intraperitoneally infected with the strains (data not shown). To study the pathogenesis of the tagged strains, the colonization of spleen, liver, and cecum was determined at different time points after infection. No significant differences in the colonization of the internal organs were observed between the parental (wild type) ST14028s strain and the tagged bacterial strains, regardless of
the route of inoculation (Table2). Table 2 The numbers of bacteria (CFU) in different organs from animals Salmonellastrains Colonization (i.p.) Colonization (i.g.) log CFU per organ log CFU per organ Liver Spleen Spleen Cecum (A) BALB/c mice ST14028s 8.5 ± 0.5 7.7 ± 0.5 7.3 ± 0.5 7.5 ± 0.3 T-prgJ 8.6 ± 0.5 7.9 ± 0.6 7.1 ± 0.5 7.5 ± 0.7 T-sipA 9.4 buy Rucaparib ± 0.5 8.4 ± 0.7 7.4 ± 0.5 7.5 ± 0.7 T-sipB 8.4 ± 0.5 7.5 ± 0.5 7.3 ± 0.5 7.7 ± 0.3 T-sopE2 8.8 ± 0.5 8.3 ± 0.7 7.5 ± 0.5 7.4 ± 0.7 T-spaO 8.5 ± 0.5 7.6 ± 0.8 7.0 ± 0.5 6.9 ± 0.6 T-sptP 8.5 ± 0.5 7.6 ± 0.5 7.0 ± 0.5 6.9 ± 0.6 (B) SCID mice ST14028s 8.7 ± 0.5 7.7 ± 0.5 7.9 ± 0.5 8.2 ± 0.6 T-prgJ 8.9 ± 0.5 7.6 ± 0.7 7.3 ± 0.7 8.4 ± 0.6 T-sipA 8.6 ± 0.5 7.5 ± 0.6 7.8 ± 0.6 8.9 ± 0.7 T-sipB 8.9 ± 0.5 8.3 ± 0.5 7.6 ± 0.5 8.8 ± 0.7 T-sopE2 8.9 ± 0.5 8.3 ± 0.6 7.6 ± 0.7 8.8 ± 0.4 T-spaO 8.5 ± 0.5 8.0 ± 0.7 8.5 ± 0.7 8.6 ± 0.5 T-sptP 8.9 ± 0.5 8.3 ± 0.6 7.6 ± 0.5 8.8 ± 0.5 *Mice were either infected intraperitoneally (i.p.) or intragastrically (i.g.) with 1 × 105CFU for BALB/c mice or 1 × 102CFU for SCID mice.