[Construction and characterization of a live attenuated Shigella flexneri 2a vaccine strain, sf301 Delta virG and dsbA33G].
Construction and characterization of a live attenuated Shigella flexneria 2a sf301 vaccine strain to prevent the endemic of shigellosis. Using Chinese majority epidemic Shigella flexneri 2a serotype sf301 as the target, p Delta virG, a deletion derivation of the virG gene in the SacB suicide vector pCVD442 and pDsbA33G, an mutant of a disulfide bond catalyst DsbA, replaced its 33 amiano acid Cystine by Glycerin in pCVD442, were used to generate a attenuated mutant strain sf301: Delta virG: DsbA33 G. Its virulence was evaluated by Sereny test, the invasive ability was detected by HeLa cell invasive assay, immunogenicity was detected by immunized Guinea pigs through inoculated guinea pigs' conjunctive sac. Sereny test was negative and HeLa invasive assay showed sf301: Delta virG: DsbA33 G retained partial invasive ability. In contrast to control group, sf301: Delta virG: DsbA33 G could induced significantly high antibody levels of IgA and IgG against sf301 LPS in animal's mucosal lavage fluids and sera in both primary immunization protocol and boosting protocol. The numbers of ASCs in local draining lymph nodes and spleens were significantly higher than control group. The immune response to sf301: Delta virG: DsbA33 G could provide completely protection from the challenge of wild type sf301. sf301: Delta virG: DsbA33 G is a safe and effective oral candidate vaccine to prevent the infection of Shigella strains.
Yang
Xiao-feng
XF
Key Laboratory of Ministry of Education for Biomedical Information Engineering, Institute for Cancer Research of Life Science and Technology, Xi'an Jiaotong University, China.
Zhou
Le
L
Zheng
Jin
J
Si
Lv-sheng
LS
Wang
Yi-li
YL
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D005260:Female; D006168:Guinea Pigs; D007114:Immunization; D022281:Shigella Vaccines / Q000276:immunology*; D012763:Shigella flexneri / Q000276:immunology* / Q000472:pathogenicity; D014613:Vaccines, Attenuated / Q000276:immunology; D014774:Virulence
D000907:Antibodies, Bacterial; D022281:Shigella Vaccines; D014613:Vaccines, Attenuated