title: Safety and immunogenicity of an oral inactivated enterotoxigenic Escherichia coli vaccine.
abstract: The safety and immunogenicity of two different lots, 001 and 003, of an oral inactivated enterotoxigenic Escherichia coli (ETEC) vaccine consisting of a mixture of formalin-killed whole bacteria expressing the most prevalent colonisation factor antigens, i.e. CFA/I, CFA/II and CFA/IV and recombinantly produced cholera B subunit (rCTB) have been evaluated in Swedish volunteers. Neither of the two vaccine preparations, containing different CFA/II-expressing strains but otherwise identical, gave rise to any significant side-effects. Mucosal immune responses, as reflected in antibody-secreting cell (ASC) responses in peripheral blood, were studied after two doses of vaccine and did not differ significantly for the two vaccine lots. Vaccination induced high levels of CTB-specific IgA ASCs in 100% of the volunteers, and significant IgA ASC responses (9- to 36-fold) were noted in 84% of them against CFA/I, in 87% against CFA/II subcomponents CS1-CS3 and in 91% against CFA/IV subfactors CS4 and/or CS5. The frequencies and magnitudes of CFA IgA ASC responses were similar when giving the vaccine with a 1 or 2 week interval. Results from serological analyses showed that the local IgA responses against CFAs are only infrequently associated with serum antibody titre rises.
authors.affiliation: Department of Medical Microbiology and Immunology, Göteborg University, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Jertborn
authors.forename: C
authors.initials: C
authors.lastname: Ahrén
authors.forename: J
authors.initials: J
authors.lastname: Holmgren
authors.forename: A M
authors.initials: AM
authors.lastname: Svennerholm
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D001428:Bacterial Vaccines / Q000008:administration & dosage* / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology*; D004927:Escherichia coli Infections / Q000517:prevention & control; D022361:Escherichia coli Vaccines; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D008875:Middle Aged; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D022361:Escherichia coli Vaccines; D007070:Immunoglobulin A; D015164:Vaccines, Inactivated