Transcription profiling of eight genetically diverse strains of mice (129/SvImJ, A/J, Balb/cJ, C3H/HeJ, C57BL/6J, Cast/EI, DBA/2J, and FVB/NJ) infected with Streptococcus, part 1

ABSTRACT: To evaluate the effect of genetic background on the immune response to streptococcal infection, eight genetically diverse strains of mice (129/SvImJ, A/J, Balb/cJ, C3H/HeJ, C57BL/6J, Cast/EI, DBA/2J, and FVB/NJ) were infected with three doses of Streptococcus zooepidemicus (500, 5,000, or 50,000 colony forming units - CFUs) by orapharyngeal aspiration. Bacterial clearance was determined by plating out dilutions of homogenized lung tissue and counting the colonies formed after 24 hours of incubation. The mean log10 CFU per ml was calculated for each strain at all timepoints. There was a range of susceptibility between the nine strains at most doses and timepoints (6, 24, and 96 hours). At the lowest dose, the 129/SvImJ and C3H/HeJ strains had significantly higher bacterial counts than five of the other strains at both 24 and 96 hours post infection. In contrast, A/J mice cleared all of the low dose inoculum from their lungs at 96 hours. At the medium dose (5,000 CFUs), the 129/Svlm and the C3H/HeJ continue to be the most susceptible strains. The DBA/2J and the C57BL/6J were the only two strains to show an overall decrease in streptococcal growth from 6 to 96 hours post infection. Following inoculation with the highest dose of Streptococcus, the Balb/cJ strain was significantly more resistant than most other strains at the 6 and 24 hour time points. However, there were no significant differences between strains at the 96 hour time point. The results thus far demonstrate significant host differences in lung response to S. zooepidemicus that strongly suggest a genetic basis for the lung response to bacterial infections.

ORGANISM(S): Mus musculus

SUBMITTER: Katherine Berman 

PROVIDER: E-TIGR-98 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress