Vaccine-specific T cells in human peripheral blood after oral immunization with an inactivated enterotoxigenic Escherichia coli vaccine.
We have examined whether oral immunization of adult Swedish volunteers with a prototype enterotoxigenic Escherichia coli vaccine would induce antigen-specific T-cell responses in blood. Volunteers were given one to three doses of the whole-cell component of the vaccine, which consisted of formalin-inactivated bacteria expressing the fimbrial colonization factor antigens I and II. Following immunization, in vitro stimulation of blood mononuclear cells with the colonization factor antigens resulted in modest proliferative responses which were accounted for mainly by CD4+ T cells and, to a lesser extent, by CD8+ T cells. A main finding of this study was that a majority of the orally immunized volunteers had circulating T cells capable of producing large quantities of gamma interferon following in vitro exposure to either of the colonization factor antigens. No interleukin 2 production could be detected in the cell cultures. These results suggest that oral immunization of humans induces the migration of specific mucosal T immunocytes from the intestine into peripheral blood.
Wennerås
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Department of Medical Microbiology and Immunology, University of Göteborg, Sweden.
Svennerholm
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Czerkinsky
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D000284:Administration, Oral; D000328:Adult; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology*; D005260:Female; D036781:Fimbriae Proteins; D006801:Humans; D007114:Immunization; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D007376:Interleukin-2; D015164:Vaccines, Inactivated; C022924:colonization factor antigens; D036781:Fimbriae Proteins; D007371:Interferon-gamma