Desensitization Effect of Preseasonal Seven-Injection Allergoid Immunotherapy with Olive Pollen on Basophil Activation: The Efficacy of Olive Pollen-Specific Preseasonal Allergoid Immunotherapy on Basophils

Abstract

Background: It has previously been demonstrated that subcutaneous immunotherapy with allergoids positively affects clinical and immunological parameters even after 7 preseasonal injections. However, its effect on basophil activation remains unclear. We investigated the effect of preseasonal allergoid immunotherapy on basophils and concomitantly assessed its clinical and immunological efficacy in olive pollen-monosensitized patients. Methods: This study enrolled 437 consecutive patients with respiratory allergy and positive skin prick tests (SPTs); 212 (48.5%) patients were sensitized to olive pollen, and 33 (7.5%) patients were sensitized to olive pollen only. Of these patients, 23 received preseasonal immunotherapy with an olive pollen allergoid. The olive pollen-specific basophil activation, the titrated nasal provocation test, the nasal symptom score, and olive pollen-specific IgE, IgG1 and IgG4 levels were evaluated before immunotherapy and 8 months after the end of immunotherapy in the follow-up visit. Results: In comparison to baseline evaluation, 7 preseasonal injections of an allergoid resulted in a significant decrease in the percentage of basophils expressing CD63 (29 vs. 7%, respectively, p < 0.0001) and a significant increase in the titrated nasal provocative dose (1/10 vs. 1/1, respectively, p < 0.01). SPT induration diameters caused by an olive pollen extract decreased (12 mm at baseline vs. 5.5 mm at follow-up, p < 0.005), as did nasal symptom score (7 at baseline vs. 3 at follow-up, p < 0.01). Olive pollen-specific IgE (17.5 vs. 50 kU/l, p < 0.012), IgG1 (0.16 vs. 2.9 µg/ml, p < 0.0001) and IgG4 (0.07 vs. 1.92 µg/ml, p < 0.0001) levels significantly increased. Conclusions: Immunotherapy with 7 preseasonal injections of an olive pollen allergoid decreases olive pollen-specific basophil activation over 8 months, an effect observed in vitro and in vivo.

Short-Term Preseasonal Immunotherapy: Is Early Clinical Efficacy Related to the Basophil Response?

“…However, there are several studies showing the increment of specific IgG antibodies by allergoid immunotherapy [22,26,27]. As shown in our study, the suppressive effect of the therapy on basophil activation at the end of treatment and at the peak of the grass pollen season after treatment further supports the powerful immunogenicity of allergoids.…”

“…However, we did not evaluate basophil activation beyond the first grass pollen season after treatment. There was a finding of a sustained decrease of basophil activation compared to baseline after 8 months of short-term, preseasonal, olive pollen allergoid immunotherapy in 1 uncontrolled study [22], but some studies have not demonstrated a change in basophil activation with immunotherapy [23,24]. A placebo-controlled trial with five-grass pollen sublingual immunotherapy did not find any alteration in allergen-induced basophil CD203c expression after 4 months of treatment, despite a symptomatic improvement of the subjects' rhinoconjunctivitis [23].…”

Food Allergy and the Oral Immunotherapy Approach

“…Moreover a decrease in the number of mast cells and basophils, determined by the SPT and the basophil activation test (BAT), respectively, has been observed in immunotherapy for aeroallergens (Gokmen et al 2012;Plewako et al 2006). Similarly, in food allergies treated with OIT protocols for milk, egg, and peanut, decreases in the serum levels of sIgE, SPTs, BATs and increase of allergen-specific IgG4 after 3-6 months of treatment have been reported (Table 2).…”

Utilization of Flow Cytometry in Immunologic and Allergic Diseases

“…Akım sitometrik bazofil aktivasyon testinin allerjen immünoterapisinin etkinliğini izlemede de kullanıldığını gösteren klinik çalışmalar vardır (34)(35)(36). Örneğin, venom immünoterapisi, Betula ve zeytin poleni immü-noterapisinin klinik etkinliğini semptom skorları yanı sıra bazofil aktivasyon testi ile gösteren çalışmalar literatürde mevcuttur (Şekil 11).…”