[Use of attenuated mutants of Pasteurella multocida strain, pathogenic to calves, in experimental mouse model studies. 4. Immunogenicity of selected revertants of temperature-sensitive, streptomycin-dependent mutants as potential vaccine strains].
Temperature-resistant or streptomycin-independent revertants were isolated from temperature-sensitive or streptomycin-dependent mutants of a Pasteurella multocida strain with pathogenicity to calf. The revertants were tested for virulence in mice and for their immunogenicity against wild-strain infection, using 100 times and more of the lethal dose. The following conclusions may be derived from the results thus obtained: 1. Most of the fully attenuated streptomycin-independent revertants failed to provide sufficient protection against wild-strain infection, following one single intraperitoneal immunization. 2. Selected streptomycin-independent revertants protect about 60% of mice immunized with one single intraperitoneal less than or approximately LD10 germ count dose, and 100% of mice immunized two times against lethal challenge. 3. Selected temperature-resistant revertants produced high immunity in mice, with one single intraperitoneally less than or approximately LD10 germ count dose protecting roughly 95 per cent of all animals against lethal infection. 4. The temperature-resistant revertant 9 b/1 and 9 b/5 and the streptomycin-independent revertant 1/14 are on the agenda as potential vaccine strains which can provide full or sufficient protection on the basis of one single immunization.
D000818:Animals; D002417:Cattle; D051379:Mice; D009154:Mutation; D010325:Pasteurella / Q000187:drug effects / Q000276:immunology* / Q000472:pathogenicity; D010326:Pasteurella Infections / Q000517:prevention & control; D013307:Streptomycin / Q000494:pharmacology; D013696:Temperature; D014613:Vaccines, Attenuated / Q000276:immunology*; D014774:Virulence
D014613:Vaccines, Attenuated; D013307:Streptomycin
Experimentelle Untersuchungen am Mäusemodell mit attenuierten Mutanten eines kälberpathogenen Pasteurella-multocida-Stammes. 4. Mitteilung: Immunogenität ausgewhlter Revertanten-von Temperatur-sensiblen und Streptomyzin-dependent Mutanten-als potentielle Impfstämme.