Oral vaccination against Helicobacter pylori with recombinant cholera toxin B-subunit.
BACKGROUND
The innocuous pure recombinant cholera toxin B-subunit (rCTB) is very attractive as a strong adjuvant for host immunization, but little is known about rCTB's gastric mucosal immunoadjuvanticity against Helicobacter pylori. The immunoadjuvanticity of rCTB against H. pylori was tested.


METHODS
Mice were immunized with sonicated H. pylori and rCTB orally or intranasally and sacrificed on day 42 after immunization. Passive cutaneous anaphylaxis (PCA) test was performed to evaluate IgE-mediated anaphylaxis with serum from mice to which H. pylori-antigen with rCTB had been administered. Immunoglobulin titer specific to H. pylori in serum, lavation of the gastrointestinal tracts and feces were examined. Gastritis in vaccinated mice after a challenge was assessed with the scoring defined from grading of gastric inflammation. H. pylori proliferation after immunization was investigated by counting colony forming units (CFU) per gram of stomach tissue.


RESULTS
PCA test exhibited no reactions against the serum from mice immunized with H. pylori-antigen with rCTB administered orally and intranasally. Oral and nasal coadministrations of rCTB significantly raised systemic and mucosal immunities against H. pylori and suppressed proliferation of H. pylori in gastric mucosa. The score of gastritis in mice immunized orally was significantly higher than that of mice immunized nasally due to postimmunization gastritis. Only oral administration of rCTB suppressed H. pylori proliferation as compared with intranasal administration and without rCTB.


CONCLUSIONS
The present study indicated that rCTB has systemic and mucosal immunoadjuvanticities against H. pylori and that oral vaccination with rCTB might additively support antibiotic eradication.
Kubota
Eiji
E
Department of Internal Medicine and Bioregulation, Nagoya City University Graduate School of Medical Sciences, Kawasumi Mizuho, Nagoya 467-8601, Japan.
Joh
Takashi
T
Tanida
Satoshi
S
Sasaki
Makoto
M
Kataoka
Hiromi
H
Watanabe
Katsushi
K
Itoh
Keisuke
K
Oshima
Tadayuki
T
Ogasawara
Naotaka
N
Togawa
Shouzo
S
Wada
Tsuneya
T
Yamada
Tomonori
T
Mori
Yoshinori
Y
Fujita
Fumitaka
F
Shimura
Takaya
T
Ohara
Hirotaka
H
Isaka
Masanori
M
Yasuda
Yoko
Y
Itoh
Makoto
M
D000276:Adjuvants, Immunologic; D000281:Administration, Intranasal; D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D002772:Cholera Toxin / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D015169:Colony Count, Microbial; D005260:Female; D005753:Gastric Mucosa / Q000276:immunology; D016481:Helicobacter Infections / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D016480:Helicobacter pylori / Q000254:growth & development / Q000472:pathogenicity*; D007114:Immunization; D051379:Mice; D008810:Mice, Inbred C57BL; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000008:administration & dosage* / Q000276:immunology
D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D011994:Recombinant Proteins; D002772:Cholera Toxin