Technological investigations with attenuated strains of Shigella for production of live vaccines. 1. Cultivation in a fermenter of an attenuated strain S. flexneri 2a with two markers.
A method was developed for cultivation of the strain Shigella flexneri 2a 77 with two attenuated markers. It ensures the preservation of the initial properties of the strain. The regimen for control of dissolved oxygen level was optimized. It was established that yeast extract is a necessary component of the nutritive medium used. The role of the phase and quantity of the inoculum for growth of the bacterial population has been clarified. Fresh fermenter culture, applied in rats, shows a high immunogenic activity. After lyophilization, the cultures retain 50-70% of the immunogenic activity of the non-lyophilized cultures. The method makes preconditions for the production of a live attenuated dysentery vaccine for oral administration.
Nenkov
P
P
Research Institute of Infectious and Parasitic Diseases, Medical Academy, Sofia, Bulgaria.
Bratoeva
M
M
Vitanov
T
T
Marinova
S
S
Denchev
V
V
Linde
K
K
D000818:Animals; D001431:Bacteriological Techniques; D005260:Female; D005285:Fermentation; D007114:Immunization; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012763:Shigella flexneri / Q000254:growth & development*; D013997:Time Factors; D014613:Vaccines, Attenuated
D014613:Vaccines, Attenuated