No abstract

The present study clearly demonstrates that SIT induces changes in the composition of serum antibodies that inhibit IgE binding, HR and FAP to a similar extent. This suggests that these measurements, individually or in combination, may be used to monitor the immunological effect of SIT, even though direct correlations to changes in clinical parameters could not be demonstrated.

Both SCIT and SLIT tablet induce significant changes in specific antibodies (IgE and IgG4) and competition assays (IgE-blocking factor, FAP, and BAT). Overall, SCIT induced larger (two- to threefold) changes than SLIT tablet, with the exception of FAP, where SLIT tablet showed a gradual increase ending at the same level as SCIT. Maximal change was generally reached after 3 months' treatment.

While some allergoids were associated with reduced allergenicity, a clear reduction in immunogenicity was observed for all allergoid products compared with the intact allergen vaccine, and the commercial allergoids tested therefore do not fulfil the allergoid concept.

We suggest that at least in birch pollen SIT, the contribution of FcgammaRIIB-mediated inhibitory signalling to SIT-IgG-induced inhibition of human basophil histamine release is of minor importance. The main contributor to the inhibitory effect of SIT-induced IgG seems to be blocking of the allergen-IgE interaction.