A Yersinia pestis lpxM-mutant live vaccine induces enhanced immunity against bubonic plague in mice and guinea pigs.
The lpxM mutant of the live vaccine Yersinia pestis EV NIIEG strain synthesising a less toxic penta-acylated lipopolysaccharide was found to be avirulent in mice and guinea pigs, notably showing no measurable virulence in Balb/c mice which do retain some susceptibility to the parental strain itself. Twenty-one days after a single injection of the lpxM-mutant, 85-100% protection was achieved in outbred mice and guinea pigs, whereas a 43% protection rate was achieved in Balb/c mice given single low doses (10(3) to 2.5 x 10(4) CFU) of this vaccine. A subcutaneous challenge with 2000 median lethal doses (equal to 20,000 CFU) of fully virulent Y. pestis 231 strain, is a 6-10-fold higher dose than that which the EV NIIEG itself can protect against.
Feodorova
V A
VA
Russian State Anti-Plague Research Institute Microbe, 46 Universitetskaya Street, Saratov 410005, Russia. feodorova@san.ru
Pan'kina
L N
LN
Savostina
E P
EP
Sayapina
L V
LV
Motin
V L
VL
Dentovskaya
S V
SV
Shaikhutdinova
R Z
RZ
Ivanov
S A
SA
Lindner
B
B
Kondakova
A N
AN
Bystrova
O V
OV
Kocharova
N A
NA
Senchenkova
S N
SN
Holst
O
O
Pier
G B
GB
Knirel
Y A
YA
Anisimov
A P
AP
D000818:Animals; D005260:Female; D017353:Gene Deletion; D006168:Guinea Pigs; D008050:Lipid A / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D010930:Plague / Q000517:prevention & control*; D010931:Plague Vaccine / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000276:immunology; D014774:Virulence; D015010:Yersinia pestis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity
D008050:Lipid A; D010931:Plague Vaccine; D014613:Vaccines, Attenuated