Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2004 Sep 1;10(17):2498-502.
doi: 10.3748/wjg.v10.i17.2498.

Construction of attenuated Salmonella typhimurium Strain expressing Helicobacter pylori conservative region of adhesin antigen and its immunogenicity

Affiliations

Construction of attenuated Salmonella typhimurium Strain expressing Helicobacter pylori conservative region of adhesin antigen and its immunogenicity

Yang Bai et al. World J Gastroenterol. .

Abstract

Aim: To construct a non-resistant and attenuated Salmonella typhimurium (S. typhimurium) strain which expresses conservative region of adhesion AB of Helicobacter pylori (H pylori) and evaluate its immunogenicity.

Methods: The AB gene amplified by PCR was inserted into the expression vector pYA248 containing asd gene and through two transformations introduced into the delta Cya, delta Crp, delta Asd attenuated Salmonella typhimurium strain, constructing balanced lethal attenuated Salmonella typhimurium strains X4072 (pYA248-AB). Bridged ELISA method was used to measure the expression of AB antigen in sonicate and culture supernatant. According to the method described by Meacock, stability of the recombinant was evaluated. Semi-lethal capacity test was used to evaluate the safety of recombinant. The immunogenicity of recombinant was evaluated with animal experiments.

Results: The attenuated S. typhimurium X4072 (pYA248-AB) which expresses AB was successfully constructed. Furthermore, bridged ELISA assay showed that the content of AB in recombinant X4072 (pYA248- AB) culture supernatant was higher than that was in thallus lytic liquor. And after recombinant X4072 (pYA248- AB) was cultured for 100 generations without selection pressure, the entire recombinant bacteria selected randomly could grow, and the AB antigen was defected positive by ELISA. The growth curve of the recombinant bacteria showed that the growth states of X4072 (pYA248) and X4072 (pYA248-AB) were basically consistent. The survival rate of C57BL/6 was still 100%, at 30 d after mice taking X4072 (pYA248-AB) 1.0 x 10(10) cfu orally. Oral immunization of mice with X4072 (pYA248-AB) induced a specific immune response.

Conclusion: In vitro recombinant plasmid appears to be stable and experiments on animals showed that the recombinant strains were safe and immunogenic in vitro, which providing a new live oral vaccine candidate for protection and care of H pylori infection.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Double restriction enzyme digestion map of recombinant plasmid PYA248-AB. Lane1: DNA marker; Lane2: PCR product; lane3: pYA248/EcoRI; lane4: pYA248-AB/EcoRI; lane5: pYA248-AB/EcoRI + SalI.
Figure 2
Figure 2
A growing curve of X4072 (PYA248) and X4072 (PYA248-AB).

Similar articles

References

    1. Janowitz HD, Abittan CS, Fiedler LM. A gastroenterological list for the millennium. J Clin Gastroenterol. 1999;29:336–338. - PubMed
    1. Kirsner JB. The origin of 20th century discoveries transforming clinical gastroenterology. Am J Gastroenterol. 1998;93:862–871. - PubMed
    1. Bai Y, Zhang YL, Jin JF, Wang JD, Zhang ZS, Zhou DY. Recombinant Helicobacter pylori catalase. World J Gastroenterol. 2003;9:1119–1122. - PMC - PubMed
    1. Blaser MJ. Polymorphic bacteria persisting in polymorphic hosts: assessing Helicobacter pylori-related risks for gastric cancer. J Natl Cancer Inst. 2002;94:1662–1663. - PubMed
    1. Bai Y, Zhang YL, Wang JD, Zhang ZS, Zhou DY. [Construction of the non-resistant attenuated Salmonella typhimurium strain expressing Helicobacter pylori catalase] Di Yi Jun Yi Da Xue Xue Bao. 2003;23:101–105. - PubMed

Publication types

MeSH terms