RAT IGE PRODUCTION .2. PRIMARY AND BOOSTER REAGINIC ANTIBODY-RESPONSES FOLLOWING INTRADERMAL OR ORAL IMMUNIZATION

  • 1 January 1976
    • journal article
    • research article
    • Vol. 30  (5) , 671-677
Abstract
Primary and booster IgE [immunoglobulin E] antibody responses were elicited in Hooded Lister rats by the intradermal injection or oral administration of very small quantities of egg albumin. Oral immunization was effected by giving antigen by stomach tube or in the drinking water. The minimum primary dose of antigen found to be effective was 1 .mu.g intradermally and 10 .mu.g orally, administered together with an i.p. injection of Bordetella pertussis adjuvant. In rats immunized with these doses, secondary responses could be evoked by giving even smaller quantities of antigen. Thus 1 ng intradermally or 1 .mu.g orally could be used without adjuvant. Smaller challenge doses were not tried. Large primary doses of antigen (> 100 .mu.g) presented by these routes were inhibitory to the production of secondary IgE responses; this effect was similar to that observed in previously reported i.p. immunization experiments. By contrast with previous experiments, tertiary responses could be obtained following immunization by these routes. This is probably a reflection of the absorption of smaller and therefore less inhibitory quantities of antigen. These results are discussed in relation to the control of IgE antibody production, current concepts of the control of antigen absorption through mucosal barriers, and possible implications for the genesis of naturally occurring IgE responses in man. The importance of this data to allergy development is discussed.