Assessment by electron-microscopy of recombinant Vibrio cholerae and Salmonella vaccine strains expressing enterotoxigenic Escherichia coli-specific surface antigens. |
| |
Authors: | V Ziethlow D Favre J-F Viret J Frey M H Stoffel |
| |
Institution: | Division of Veterinary Anatomy, Vetsuisse Faculty University of Berne, Berne, Switzerland. |
| |
Abstract: | Diarrhoea caused by enterotoxigenic Escherichia coli (ETEC) requires adhesion of microorganisms to enterocytes. Hence, a promising approach to immunoprophylaxis is to elicit antibodies against colonisation factor antigens (CFAs). Genes encoding the most prevalent ETEC-specific surface antigens were cloned into Vibrio cholerae and Salmonella vaccine strains. Expression of surface antigens was assessed by electron-microscopy. Whereas negative staining was effective in revealing CFA/I and CS3, but not CS6, immunolabelling allowed identification of all surface antigens examined. The V. cholerae vaccine strain CVD103 did not express ETEC-specific colonisation factors, whereas CVD103-HgR expressed CS3 only. However, expression of both CFA/I and CS3 was demonstrated in Salmonella Ty21a. |
| |
Keywords: | Colonising factor antigens diarrhoea enterotoxigenic Escherichia coli (ETEC) immunogold labelling surface antigens vaccine |
|
|