SELECTED ARTICLES FROM THE RECENT LITERATURE 2008

5/21/2008

Sequence of Immunologic Events and Symptom Relief Resulting from Allergen Immunotherapy (SCIT) to Grass Pollen

Summary
The authors evaluated patients receiving SCIT to grass pollen. Eighteen subjects with severe seasonal allergic rhinitis were evaluated using a randomized double-blind placebo-controlled protocol. The authors evaluated symptoms, early and late phase skin responses to intradermal injection of allergen, and cellular responses to grass pollen allergen. In addition, sera were measured for allergen-specific IgG4, IgA, and inhibitory activity in biologic assays of IgE responses.

In the active group, significant IL-10 production occurred early, at low allergen doses and about the same time as the inhibition of the late skin responses appeared. This was at 2 to 4 weeks. On the other hand, serum-specific IgG4, IgA, and inhibitory antibody activity for basophil histamine release as well as IgE-facilitated allergen binding to B cells occurred at a later stage (6 to 12 weeks), at higher allergen doses.

The authors concluded that IL-10 production, occurring earlier on, before clinically effective doses, played a pivotal role in induction of later changes. It was not until such later changes appeared, at higher allergen doses, however, that symptom relief occurred.

Reference
Francis JN, et al. Grass pollen immunotherapy: IL-10 induction and suppression of late responses precedes IgG4 inhibitory antibody activity. J Allergy Clin Immunol 2008; 121(5):1120-1125.

 

<-- BACK