BACKGROUND:Grass pollen immunotherapy is an effective treatment for seasonal allergic rhinitis that provides the opportunity to study the induction and maintenance of allergen-specific immune tolerance. OBJECTIVES: We investigated the relationship between clinical responsiveness, regulatory cytokine production, and antibody responses to allergen during 1 year of immunotherapy. METHODS:Eighteen subjects with severe seasonal allergic rhinitis were randomized double-blind to receive active or placebo injections of an alum-adsorbed grass pollen vaccine (Alutard SQ). Subjects underwent repeated testing of early- and late-phase skin responses to intradermal allergen, and cellular responses to grass pollen allergen were tested. Sera were tested for allergen-specific IgG4, IgA, and inhibitory activity in biologic assays of IgE responses. RESULTS:Grass pollen immunotherapy was effective in reducing overall symptom scores (P < .05) and conjunctival reactivity (P < .05). In the active group significant IL-10 production occurred early at low allergen doses and at a similar time as inhibition of late skin responses at 2 to 4 weeks. Serum allergen-specific IgG4, IgA, and inhibitory antibody activity for basophil histamine release and IgE-facilitated allergen binding to B cells occurred later, at 6 to 12 weeks, at higher allergen doses and preceded inhibition of early skin responses. CONCLUSION:IL-10 responses occur early but at immunotherapy doses that are not clinically effective. Later induction of inhibitory antibodies, including IgG4 and IgA, might be required for efficacy through modulation of IgE-mediated events.
RCT Entities:
BACKGROUND: Grass pollen immunotherapy is an effective treatment for seasonal allergic rhinitis that provides the opportunity to study the induction and maintenance of allergen-specific immune tolerance. OBJECTIVES: We investigated the relationship between clinical responsiveness, regulatory cytokine production, and antibody responses to allergen during 1 year of immunotherapy. METHODS: Eighteen subjects with severe seasonal allergic rhinitis were randomized double-blind to receive active or placebo injections of an alum-adsorbed grass pollen vaccine (Alutard SQ). Subjects underwent repeated testing of early- and late-phase skin responses to intradermal allergen, and cellular responses to grass pollen allergen were tested. Sera were tested for allergen-specific IgG4, IgA, and inhibitory activity in biologic assays of IgE responses. RESULTS: Grass pollen immunotherapy was effective in reducing overall symptom scores (P < .05) and conjunctival reactivity (P < .05). In the active group significant IL-10 production occurred early at low allergen doses and at a similar time as inhibition of late skin responses at 2 to 4 weeks. Serum allergen-specific IgG4, IgA, and inhibitory antibody activity for basophil histamine release and IgE-facilitated allergen binding to B cells occurred later, at 6 to 12 weeks, at higher allergen doses and preceded inhibition of early skin responses. CONCLUSION:IL-10 responses occur early but at immunotherapy doses that are not clinically effective. Later induction of inhibitory antibodies, including IgG4 and IgA, might be required for efficacy through modulation of IgE-mediated events.
Authors: Guy W Scadding; Moises A Calderon; Mohamed H Shamji; Aarif O Eifan; Martin Penagos; Florentina Dumitru; Michelle L Sever; Henry T Bahnson; Kaitie Lawson; Kristina M Harris; Audrey G Plough; Joy Laurienzo Panza; Tielin Qin; Noha Lim; Nadia K Tchao; Alkis Togias; Stephen R Durham Journal: JAMA Date: 2017-02-14 Impact factor: 56.272