Immunological response of recombinant H. pylori multi-epitope vaccine with different vaccination strategies.
OBJECTIVE
To investigate different protective effects of recombinant H. pylori multi-epitope antigen (rIB) with cholera toxin subunit B (rCTB) as the intramolecular/extramolecular adjuvant though different immunization routes in a Helicobacter pylori infected mouse model.


METHODS
By using rCTB as the intramolecular/extramolecular adjuvant of rIB, BALB/c mice were immunized through oral administration or intramuscular injection, on day 0, 14, 28. Every 14 days, ELISA was used to detect serum specific IgG and IgA titers after immunization. After the last immunization, H. pylori SS1 challenge was performed, and urease test, Gram staining after smearing of mouse gastric tissue, PCR, pathology and immunohistochemistry were used to evaluate preventive effect of the recombinant protein vaccine.


RESULTS
After immunization three times, intramolecular injection could induce high titers of serum specific IgG antibody, and the antibody titer in rIB group, rCTB+rIB and rBIB group was 2000, 5000 and 7500, respectively (P < 0.05). Specific IgA antibody was only detected in rBIB oral administration group. The immune protection rate in rBIB oral administration group was significantly higher than that in rBIB intramolecular injection group (33.3% vs. 83%), indicating significant difference.


CONCLUSIONS
rCTB has good intramolecular/extramolecular immune adjuvant effects, and its intramolecular immune adjuvant effect is better. Both intramolecular injection and oral administration of rBIB have immune protective effect against H. pylori challenge, and oral administration of rBIB exerts better immune protective effect.
College of Basic and Forensic Medicine of Sichuan University Chengdu 610041, Sichuan, China.
Baoning
B
Wang
College of Basic and Forensic Medicine of Sichuan University Chengdu 610041, Sichuan, China ; Sichuan Vaccine Technology Co., Ltd. Chengdu 610041, Sichuan, China.
Xing
X
Pan
College of Basic and Forensic Medicine of Sichuan University Chengdu 610041, Sichuan, China.
Hongren
H
Wang
Sichuan Vaccine Technology Co., Ltd. Chengdu 610041, Sichuan, China.
Yongjun
Y
Zhou
Sichuan Vaccine Technology Co., Ltd. Chengdu 610041, Sichuan, China.
Jie
J
Zhu
College of Basic and Forensic Medicine of Sichuan University Chengdu 610041, Sichuan, China ; Sichuan Vaccine Technology Co., Ltd. Chengdu 610041, Sichuan, China.
Jing
J
Yang
College of Basic and Forensic Medicine of Sichuan University Chengdu 610041, Sichuan, China.
Wanyi
W
Li
D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000008:administration & dosage* / Q000276:immunology; D001428:Bacterial Vaccines / Q000008:administration & dosage* / Q000276:immunology; D002772:Cholera Toxin / Q000008:administration & dosage; D000939:Epitopes; D005260:Female; D016481:Helicobacter Infections / Q000097:blood / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000276:immunology*; D007070:Immunoglobulin A / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood*; D007273:Injections, Intramuscular; D008297:Male; D008807:Mice, Inbred BALB C; D013997:Time Factors; D014611:Vaccination / Q000379:methods*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D000939:Epitopes; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D014614:Vaccines, Synthetic; D002772:Cholera Toxin
Helicobacter pylori; adjuvant; cholera toxin subunit B; immunological response; recombinant vaccine