IgE antibodies against plant/insect CCD determinants were shown to have both strict specificity and high affinity, so in principle they might be expected to lead to clinical symptoms just as habitual for anti-peptide IgE. In vitro experiments (histamine-release tests) with polyvalent glyco-allergens corroborated this view. Provocation tests with patients as well as empirical evidence however, indicate that CCDs never cause any ponderable allergic symptoms. It is assumed that the frequent contact with CCD containing foods induces tolerance akin a specific immune therapy.