Immunological responses unique to virulent F. tularensis Schu4 in the mouse model of infection

ABSTRACT: Francisella tularensis is a category A select agent based on its infectivity and virulence but disease mechanisms in F. tularensis infection remain poorly understood. A murine pulmonary model of infection was therefore employed to characterize the host immune response to F. tularensis infection and to discern differences in responses to infection with the highly virulent Type A F. tularensis strain Schu4 and to the less virulent Type B live vaccine strain (LVS). Mice were infected intranasally with F. tularensis Schu4 or LVS and organ lesions were assessed 48 and 120 hours after infection. Experiments were also conducted to assess and compare the host immune response to infection using global transcriptional analysis. Mice were infected via low dose aerosol with F. tularensis Schu4 or LVS strains, and transcriptional response in the lungs and spleen was monitored using full mouse genome microarrays at 12, 24, 48, and 120 hours after infection. We found differential and temporal differences in expression of cytokine and chemokine genes, CD molecules, apoptosis, leukocytes and adhesion receptors, and immunological signaling between infection with Schu4 and LVS strains. The transcriptional differences coincided with marked differences in the timing and extent of organ lesions in mice infected with the LVS and Schu4 strains. Thus, these studies revealed both temporal and qualitative differences in the host immune response to infection with virulent F. tularensis Schu4 compared to infection with LVS. 18 mice total, 2 uninfected controls, 2 mice per time point, time points were 12 hour/24 hour/48 hour/ 120 hour post infection, 2 infection groups: LVS and Schu4 infection. Lung and spleen were harvested at each time point, poly A RNA was extracted, converted to cDNA, labeled and hybridized in triplicate

ORGANISM(S): Mus musculus

SUBMITTER: Luke Kingry 

PROVIDER: E-GEOD-22203 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress