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Notizen: We investigated the proliferative response of lymphocytes from mite-sensitive patients (RAST D.far 〉 3.5 PRU/ml) in the presence of the major allergen Der.f.I purified from Dermatophagoides farinae. Comparative studies were carried out with peripheral blood mononuclear cells from non-atopic donors (RAST = 0), and from patients undergoing hyposensitization treatment (5 to 24 months). According to Student's t-test, there was no significant difference in the Der.f. I-induced proliferation of peripheral blood mononuclear cells from normal donors, untreated atopic patients and hyposensitized patients. In conclusion, it was impossible to discriminate between normal donors, atopic patients and hyposensitized patients with regard to their circulating lymphocyte responses to the purified major allergen Der.f.I.

Notizen: Background Anti-idiotypic antibodies (anti-Ids) to specific IgE antibodies are formed spontaneously during an anti-allergen immune response and can be induced by immunotherapy. Although anti-Ids can down-regulate the production of IgF. antibodies, at least in experimental models, their possible role in the modulation of target cell reactivity remains ill-defined.Objective The capacity of human anti-Ids to modulate the release of histamine was examined in an in vitro system of human basophil degranillation. Anti-Ids were prepared from the serum of six Dermatophagoides pteranyssinus (DP)-hypersensitive patients suffering from atopic dermatitis and who had never been desensitized. Basophils were obtained from the blood of atopic donors. The extent of histaminc release was determined using a fluorometric assay.Results We show that: anti-Ids trigger the release of histamine in an allergen-specific, dose- and IgE-dependent manner; the release is not due to the presence of allergen and/ or anti-IgE antibodies: and that the degranulating activity can be removed by absorption with affinity-purified anti-Dp antibodies of the corresponding patient.Conclusion These results indicate that spontaneously produced human anti-Ids can modulate the reactivity of human basophils.

Notizen: Background Calcium phosphate-adsorbed allergen extracts are used for subcutaneous immunotherapy to avoid the use of aluminium adjuvants.Objectives A double-blind, placebo-controlled study was performed in order to confirm the safety and assess the efficacy of a standardized five-grass-pollen extract adsorbed onto calcium phosphate for specific immunotherapy (IT).Methods Twenty-nine patients with seasonal rhinoconjunctivitis were randomized to receive either the active preparation (16 patients) or placebo (13 patients), in a 1-year study. During the increasing dose phase, an extract ranging from 0.1 IR per ml to 50 IR per ml was administered at a rate of one subcutaneous injection per week until a maintenance dose was reached. The patients were assessed by symptom diary and rescue medications during seasonal exposure and specific nasal and skin reactivity before and after IT. Immunological parameters (specific IgE and IgG4 antibodies) were assessed before, during and after IT.Results The overall symptoms score (mean AUC) was not significantly different between the IT group and the placebo group during grass-pollen exposure (49.6 vs. 56, respectively). The total medication score (mean AUC) was significantly lower in the IT group than in the placebo group (11 vs. 41, P 〈 0.01, Mann–Whitney U-test). The cumulative symptom/medication score was significantly lower in the IT group than in the placebo group (64.5 vs. 102.3, P 〈 0.05, U-test). A significant increase in nasal reactivity threshold was observed after IT in the IT group (21. 4 IR/mL before IT vs. 63.4 IR/mL after IT, P 〈 0.01, Wilcoxon), whereas no significant changes were observed in the placebo group (31.0 IR/mL before IT vs. 37.7 IR/mL after IT). IT induced a significant reduction in grass pollen cutaneous reactivity in the actively treated group (P 〈 0.001). A significant increase in serum-specific IgG4 antibody response was observed in the IT group (3.1% before IT vs. 10.1% after IT, P 〈 0.001). Nine patients in the IT group developed moderate immediate systemic reactions vs. two patients in the placebo group.Conclusion Specific immunotherapy with calcium phosphate-adsorbed standardized grass pollen extract was safe and effective for the treatment of patients with seasonal allergic rhinoconjunctivitis.

Notizen: In a series of 102 patients consulting for allergic reactions following hymenoptera sting, fifty-two of them, who had experienced one or more severe systemic adverse reactions were selected for rush immunotherapy.The method employed made it possible to attain the maintenance dose of 100 μg of venom in 3 days. Patient tolerance was excellent, no serious side-effect was observed; immunotherapy never had to be stopped. Clinical effectiveness seems to be very satisfactory, since no abnormal reaction was reported in seven patients who later were spontaneously stung, and in fourteen patients who received an induced insect sting. The level of IgG antivenom antibodies rose regularly from the first month onwards to remain at a stable level.Because of its safety and effectiveness, it appears that this method should be recommended for immunotherapy in patients who are allergic to hymenoptera stings.