SUPPRESSION OF DELAYED-TYPE HYPERSENSITIVITY AND IGE ANTIBODY-RESPONSES TO OVALBUMIN BY INTRANASAL ADMINISTRATION OF ESCHERICHIA-COLI HEAT-LABILE ENTEROTOXIN-B SUBUNIT-CONJUGATED OVALBUMIN

Oral administration of a small amount of antigen conjugated cholera to xin B subunit is known to induce tolerance to the antigen. In the pres ent experiments, whether nasal administration of allergen conjugated t o Escherichia coli heat-labile toxin B subunit (LTB) induced tolerance was examined in BALC/c mice. A single administration of small amount of LTB-coupled ovalbumin (OVA) suppressed the induction of delayed-typ e hypersensitivity and IgE antibody responses to OVA which was adminis tered parenterally after nasal administration of LTB-coupled OVA. The antigen-specific suppression was abrogated by the addition of the holo toxin to LTB-coupled OVA. The suppression, induced by nasal administra tion with a small amount of allergen conjugated to a mucosa-binding mo lecule, may be applicable for preventing the development of allergy. C opyright (C) 1997 Elsevier Science Ltd.