Accession Number : ADA155646


Title :   Differences in Susceptibility of Inbred Mice to Bacillus anthracis


Corporate Author : ARMY MEDICAL RESEARCH INST OF INFECTIOUS DISEASES FORT DETRICK MD


Personal Author(s) : Welkos, Susan L ; Keener, Theresa J ; Gibbs, Paul H


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a155646.pdf


Report Date : 26 Apr 1985


Pagination or Media Count : 33


Abstract : Animal species differ in their resistance both to infection by B. anthracis and to anthrax toxin. A mouse model was developed to study the basis of these host differences and the pathogenesis of infection. When infected with the virulent B. anthracis strain Volume 1B, all eight strains of inbred mice tested had low LD50 values (5 to 30 spores). However, analysis of time-to-death (TTD) data revealed significant differences between the strains, which could be divided into three groups: most susceptible (A/J, DBA/2J, and C3H/HeN); intermediate (C57BL/6J, C57L/J, and C58/J); and least susceptible (CBA/J and C57BR/cdJ). In contrast, the mice were distinctly susceptible or resistant to lethal infection by Sterne vaccine strain. The LD50 of the susceptible A/J and DBA/2J mice was approximately 1,000 Sterne spores; whereas the remaining six relatively resistant strains were killed only by 0.2 to 2 x 10,000,000 spores. Mice lethally infected with B. anthracis had an acute course, characterized by extensive gelatinous edema and large concentrations of bacilli in the blood and organs (e.g. 1,000,000,000 CFU/g spleen). To study susceptibility to anthrax toxin, the protective antigen (PA) and lethal factor (LF) components of the toxin were injected i.v. into A/J and CBA/J mice. As reported earlier for various animal species, susceptibilities of the mice to anthrax toxin appeared to be independent of that to infection. The toxin LD50 values for both strains were about 12 micrograms PA combined with 2.4 micrograms LF.


Descriptors :   *ANTHRAX , *IMMUNITY , *PATHOGENESIS , *BACILLUS ANTHRACIS , SPORES , STRAINS(BIOLOGY) , LETHALITY , MICE , ANTIGENS , VACCINES , BACTERIAL TOXINS , HOSTS(BIOLOGY) , ORGANS(ANATOMY) , RESISTANCE(BIOLOGY) , ANATOMICAL MODELS , EDEMA


Subject Categories : Anatomy and Physiology
      Medicine and Medical Research


Distribution Statement : APPROVED FOR PUBLIC RELEASE