ABSTRACT
PURPOSE: Study on the pathogen and the pathogen-related disease require the information at both cellular and organism level. However, lack of appropriate high-quality antibodies and the difference between the experimental animal models make it difficult to analyze in vivo mechanism of pathogen-related diseases. For more reliable research on the infection and immune-response of pathogen-related diseases, accurate analysis is essential to provide spatiotemporal information of pathogens and immune activity to avoid false-positive or mis-interpretations. In this regards, we have developed a method for tracking Francisella tularensis in the animal model without using the specific antibodies for the F. tularensis. MATERIALS AND METHODS: A dual reporter plasmid using GFP-Lux with putative bacterioferritin promoter (pBfr) was constructed and transformed to F. tularensis live vaccine strain to generate F. tularensis LVS (FtLVS)-GFP-Lux for both fluorescence and bioluminescence imaging. For vaccination to F. tularensis infection, FtLVS and lipopolysaccharide (LPS) from FtLVS were used. RESULTS: We visualized the bacterial replication of F. tularensis in the cells using fluorescence and bioluminescence imaging, and traced the spatio-temporal process of F. tularensis pathogenesis in mice. Vaccination with LPS purified from FtLVS greatly reduced the bacterial replication of FtLVS in animal model, and the effect of vaccination was also successfully monitored with in vivo imaging. CONCLUSION: We successfully established dual reporter labeled F. tularensis for cellular and whole body imaging. Our simple and integrated imaging analysis system would provide useful information for in vivo analysis of F. tularensis infection as well as in vitro experiments, which have not been fully explained yet with various technical problems.
Subject(s)
Animals , Mice , Antibodies , Fluorescence , Francisella tularensis , Francisella , Immunodeficiency Virus, Feline , In Vitro Techniques , Methods , Models, Animal , Plasmids , Vaccination , Whole Body ImagingABSTRACT
Strains of
Subject(s)
Air Conditioning , Bacterial Proteins/genetics , DNA-Directed RNA Polymerases/genetics , Francisella , Flavoproteins/genetics , Water Microbiology , Base Sequence , China , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Francisella/classification , Francisella/genetics , Francisella/isolation & purification , Molecular Sequence Data , Molecular Typing , Phylogeny , /genetics , Sequence Analysis, DNAABSTRACT
Tularemia is a major laboratory acquired zoonoses caused by Francisella tularensis that have high virulence, and usually transmitted to humans from direct contact with infected wild animals like rabbits or insect vectors like ticks. Clinical tularemia can be divided with 6 major syndromes that are delineated by the mode of organism aquisition, in which ulceroglandular type is the most common. F. tularensis have 3 different biogroups which have homogeneous antigenecity, type A (biogroup tularensis), type B (biogroup palearctica) and biogroup novicida, and can be confirmed by serology most frequently. In the domestic area, there was no reports of tularemia in humans or presence of bacteria in the reservoirs. Authers experienced a case of tularemia which is suspected as F. tularensis type B, ulceroglandular type. A healthy 40-year-old man admitted the hospital for lymph node swelling in both axillary and upper arm area and for furuncles in both forearm and palm. He contacted with dead rabbit and eated it after cooking before 20 days from admission day. In laboratory cultures, F. tularensis did not grow in any of the routine or anaerobic culture media except for one blood agar plate at 5 days. After subculturing that to cystine containing chocolate agar plate at 37C degree, 5% CO2 incubator, we could see the accelerating growth of colony. In microbiological test, it was oxidase and urease negative. In acid production in cystine trypticase agar base, it was glucose positive and sucrose, maltose, glycerol negative. In agglutinating test, F. tularensis antiserum titer (Difco, USA) with isolates was 1:160 or over and antibody titer to F. tularensis antigen (Difco, USA) was 1:320 or over. Anti-F. tularensis-IF assay and Anti-F. tularensis-indirect-EIA with isolates were positive.