Induction of protection against oral infection with cytotoxin-producing Escherichia coli O157:H7 in mice by shiga-like toxin-liposome conjugate.
We have previously reported that purified Shiga-like toxins (SLT), SLT-I and SLT-II coupled with liposomes induced a substantial amount of anti-SLT-I and anti-SLT-II IgG antibody production, respectively, in mice. The levels of anti-SLT antibody in the sera of SLT-liposome-immune mice correlated well with the protection against subsequent challenge with SLT. In this study, mice were immunized intraperitoneally with the mixture of SLT-I-liposome and SLT-II-liposome and protection against oral infection with cytotoxin-producing Escherichia coli O157:H7 was evaluated. All of the mice that received immunization with the mixture of SLT-I-liposome and SLT-II-liposome were protected against subsequent intravenous challenge with 10 LD50 of either SLT-I or SLT-II. Eight weeks after primary immunization, mice were inoculated intragastrically with 10(9) CFU of E. coli O157:H7 strain 96-60. All SLT-liposome-immune mice tested survived without any apparent symptom while control mice died within 5 days. In addition, as shown by other antigen-liposome conjugates, SLT-liposome induced undetectable anti-SLT IgE antibody production while they induced substantial amounts of anti-SLT IgG antibodies. These results suggest that SLT-liposome conjugate may serve as a candidate vaccine that induces protection against cytotoxin-producing E. coli infection.
Department of Bacterial and Blood Products, National Institute of Infectious Diseases, Tokyo, Japan.
T
T
Fukuda
T
T
Kimiya
M
M
Takahashi
Y
Y
Arakawa
Y
Y
Ami
Y
Y
Suzaki
S
S
Naito
A
A
Horino
N
N
Nagata
S
S
Satoh
F
F
Gondaira
J
J
Sugiyama
Y
Y
Nakano
M
M
Mori
S
S
Nishinohara
K
K
Komuro
T
T
Uchida
D000818:Animals; D001427:Bacterial Toxins / Q000008:administration & dosage* / Q000276:immunology*; D003603:Cytotoxins / Q000276:immunology; D004337:Drug Carriers; D004927:Escherichia coli Infections / Q000276:immunology* / Q000517:prevention & control*; D005260:Female; D008081:Liposomes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009059:Mouth Diseases / Q000276:immunology* / Q000382:microbiology* / Q000517:prevention & control*; D022603:Shiga Toxins
D001427:Bacterial Toxins; D003603:Cytotoxins; D004337:Drug Carriers; D008081:Liposomes; D022603:Shiga Toxins