Allergen-specific immunotherapy reduced to three injections
Published Online: April 1, 2012
Allergen-specific immunotherapy is the only disease modifying treatment of allergies, but it requires numerous allergen administrations over three to five years, so that less than 5% of allergy patients choose immunotherapy.
In a recent article in The Journal of Allergy and Clinical Immunology (JACI), Senti et al. could reduce the number of allergen injections to three by enhancing antigen presentation. Firstly, the allergen was injected directly into lymph nodes. Secondly, the allergen, recombinant cat dander allergen Fel d 1, was fused with an intracellular translocation sequence and with an invariant chain to enhance presentation via MHC class II to CD4 T cells. In a double blind placebo controlled trial cat dander allergic patients received three intralymphatic injections within two months, either with modified Fel d 1 or placebo.
Injections were practically painless and safe. Such rapid intracellular translocation of the allergen has the additional advantage to reduce IgE cross linking on mast cells, reducing skin test reactivity approx. 100-fold. Induction of regulatory T cells correlating to IgG4 responses was observed, and nasal tolerance increased 74-fold (vs. placebo p<0.001).
Intralymphatic immunotherapy with modified recombinant Fel d 1 elicited no adverse events, and three injections were sufficient to render cat-allergic patients tolerant. Reduced treatment duration may make immunotherapy more attractive for today’s busy patient.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.