[Stable expression and immunogenicity in a attenuated Salmonella typhi strain of coli surface antigen-6 of enterotoxigenic Escherichia coli].
A gene fragment encoding for surface antigen CS6 of enterotoxigenic of Escherichia coli has been cloned into the plasmid pXL670, a new recombinant plasmid pSS64 was obtained by transforming E. coli X6097 with asd gene deletion. A safe and effective E. coli/S. typhi bivalent candidate vaccine was constructed by introducing pSS64 into delta aroA, delta aroC, delta asd Salmonella typhi. The vaccine strain is still stable in the absence of antibiotics. Animal tests demonstrated that this strain, when administered subcutaneously in mice, could provide significant protection against the intraperitoneal challenge from wild S. typhi Ty2. Immunization of rabbit with this strain raised specific antibody responses against CS6 and Vi antigen of S. typhi. This study lays the foundation for the construction of a new E. coli/S. typhi bivalent live oral vaccine.
Teng
J
J
Institute of Biotechnology, Academy of Military Medical Sciences, Beijing 100071.
Rui
X
X
Zhang
Y
Y
Zhang
Z
Z
Su
G
G
D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000276:immunology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology*; D005260:Female; D008297:Male; D051379:Mice; D010957:Plasmids; D011817:Rabbits; D012485:Salmonella typhi / Q000276:immunology*; D014436:Typhoid-Paratyphoid Vaccines / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology*
D000942:Antigens, Bacterial; C098406:CS6 antigen, E coli; D029968:Escherichia coli Proteins; D014436:Typhoid-Paratyphoid Vaccines; D014614:Vaccines, Synthetic