THE STABILITY OF BIOLOGICAL PROPERTIES IN THE ANTHRAX STI-1 VACCINE STRAIN
ARMY BIOLOGICAL LABS FREDERICK MD
Pagination or Media Count:
In cultures of the STI-1 strain, which over a period of 20 years following isolation were subjected to periodic reinoculation and storage in 30 glycerin, signs of dissociation were observed. These were expressed in the appearance of the nature of growth on solid and liquid nutrient media which was not typical for the anthrax microbe. A 3rd generation sport culture of the STI- 1 strain, which had been stored in a desiccated lyophilized form for 18 years, preserved all the biological features characteristic for the strain, both in regards to type of growth on nutrient media as well as in regards to reactogenicity and immunogenicity for animals. Storage of spore cultures of a strain -- standards in a desiccated state, must be recognized as the optimum conditions for the stabilization of the properties of the strain. On the basis of the data from the study of the new standard STI-1 vaccine strain 1962 it must be recommended that this standard culture be used for the production of live anthrax vaccine, and also for scientific-research work, using it to replace all the other cultures lines of this strain being used in various laboratories.