Intestinal immune responses to an inactivated oral enterotoxigenic Escherichia coli vaccine and associated immunoglobulin A responses in blood.
An inactivated oral enterotoxigenic Escherichia coli (ETEC) vaccine against ETEC diarrhea was given to 25 adult Swedish volunteers. The vaccine consisted of formalin-killed E. coli bacteria expressing the most common colonization factor antigens (CFAs), i.e., CFA/I, -II, and -IV, and recombinantly produced cholera B subunit (CTB). Immunoglobulin A (IgA) antibody responses in intestinal lavage fluid to CTB and CFAs were determined and compared with corresponding responses in stool extracts and serum as well as with IgA antibody-secreting cell (ASC) responses in peripheral blood. Two doses of vaccine induced significant IgA responses to the different CFAs in lavage fluid in 61 to 87% of the vaccinees and in stool in 38 to 81% of them. The most frequent responses were seen against CFA/I. The magnitudes of the antibody responses against CTB and CFA/I in stool correlated significantly (CTB, P < 0.01; CFA/I, P < 0. 05) with those in intestinal lavage. Intestinal lavage responses against CFAs were best reflected by the ASC responses, with the sensitivity of the ASC assay being 80 to 85%, followed by stool (sensitivity of 50 to 88%) and serum antibody (sensitivity of 7 to 65%) analyses. CTB-specific immune responses were seen in >90% of the vaccinees in all assays.
Ahrén
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C
Departments of Medical Microbiology and Immunology, Göteborg University, Göteborg, Sweden.
Jertborn
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M
Svennerholm
A M
AM
D000284:Administration, Oral; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D001428:Bacterial Vaccines / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology*; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007413:Intestinal Mucosa / Q000276:immunology*; D008297:Male; D015164:Vaccines, Inactivated / Q000276:immunology
D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007070:Immunoglobulin A; D015164:Vaccines, Inactivated