To cite this article: Gadermaier E, Staikuniene J, Scheiblhofer S, Thalhamer J, Kundi M, Westritschnig K, Swoboda I, Flicker S, Valenta R. Recombinant allergen–based monitoring of antibody responses during injection grass pollen immunotherapy and after 5 years of discontinuation. Allergy 2011; 66: 1174–1182.
Background: Subcutaneous injection immunotherapy (SCIT) is considered as antigen-specific and disease-modifying treatment with long-lasting effect.
Methods: We used a panel of recombinant grass pollen allergens for analyzing allergen-specific IgE, IgG1-IgG4, IgM, IgA, and light-chain (kappa, lambda) responses in grass pollen–allergic patients who had received one course of injection immunotherapy (SCIT) with an aluminum hydroxide-adsorbed grass pollen extract or only anti-inflammatory treatment. Serum samples were analyzed before and after 5 months of treatment as well as after 5 years.
Results: After 5 months of SCIT but not of anti-inflammatory treatment, IgG1 > IgG4 > IgG2 > IgA antibody responses using both kappa and lambda light chains specific for major grass pollen allergens (Phl p 1, Phl p 5, Phl p 6, Phl p 2) increased significantly, whereas specific IgM or IgG3 levels were unaltered. Allergen-dependent basophil degranulation was only inhibited with SCIT sera containing therapy-induced allergen-specific IgG antibodies. Likewise, decreases in Phl p 1- and Phl p 5-specific IgE levels and significant (P < 0.001) reduction in symptom and medication scores were found only in the SCIT group but not in the group of patients receiving anti-inflammatory treatment. After 5 years, allergen-specific IgG antibody levels in the SCIT group had returned to baseline levels and there was no significant difference regarding symptoms between the SCIT and non-SCIT groups.
Conclusion: The results from our observational study demonstrate that only SCIT but not anti-inflammatory treatment induces allergen-specific IgG and reduces boosts of allergen-specific IgE production but that one SCIT course was not sufficient to achieve long-term immunological and clinical effects.