Title Protective Immune Response of Bacterially-Derived Recombinant FaeG in Piglets
Author Huang Yahong1, Wanqi Liang2, Aihu Pan3, Zhiai Zhou4, Qiang Wang1, Cheng Huang1, Jianxiu Chen1, and Dabing Zhang*2
Address 1Department of Biological Science and Technology, School of Life Sciences of Nanjing University, Nanjing 210093, China, 2Shanghai Jiao Tong University-Shanghai Institutes for Biological Sciences-Pennsylvania State University Joint Center for Life Sciences, Key Laboratory of Microbial Metabolism, Ministry of Education, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China, 3Shanghai Key Laboratory of Agricultural Genetics and Breeding, Agro-biotech Research Center, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China, 4Shanghai Key Laboratory of Agricultural Genetics and Breeding, the Institute of Animal and Veterinary Sciences, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China
Bibliography Journal of Microbiology, 44(5),548-555, 2006,
DOI
Key Words Enterotoxigenic Escherichia coli (ETEC), proteinaceous fimbriae, recombinant FaeG, adhesion
Abstract FaeG is the key factor in the infection process of K88ad enterotoxigenic Escherichia coli(ETEC) fimbrial adhesin. In an attempt to determine the possibility of expressing recombinant FaeG with immunogenicity for a new safe and high-production vaccine in E. coli, we constructed the recombinant strain, BL21 (DE3+K88), which harbors an expression vector with a DNA fragment of faeG, without a signal peptide. Results of 15% SDS-polyacrylamide slab gel analysis showed that FaeG can be stably over-expressed in BL21 (DE3+K88) as inclusion bodies without FaeE. Immunoglobulin G (IgG) and M (IgM) responses in pregnant pigs, with boost injections of the purified recombinant FaeG, were detected 4 weeks later in the sera and colostrum. An in vitro villius-adhesion assay verified that the elicited antibodies in the sera of vaccinated pigs were capable of preventing the adhesion of K88ad ETEC to porcine intestinal receptors. The protective effect on the mortality rates of suckling piglets born to vaccinated mothers was also observed one week after oral challenge with the virulent ETEC strain, C83907 (K88ad, CT+, ST+). The results of this study proved that the adhesin of proteinaceous bacterial fimbriae or pili could be overexpressed in engineered E. coli strains, with protective immune responses to the pathogen.
Download PDF JM 44(5)-10.pdf