"Auto-anti-IgE": naturally occurring IgG anti-IgE antibodies may inhibit allergen-induced basophil activation.

BACKGROUND: Naturally occurring IgE-specific IgG autoantibodies have been identified in patients with asthma and other diseases, but their spectrum of functions is poorly understood. OBJECTIVE: Address the hypothesis that: (i) IgG anti-IgE autoantibodies are detectable in the serum of all subjects but elevated in asthmatic patients regardless of atopic status as compared with controls; (ii) some activate IgE-sensitized basophils; and (iii) some inhibit allergen-induced basophil activation. METHODS: IgE-specific IgG autoantibodies were detected and quantified in sera using ELISA. Sera were examined for their ability to activate IgE-sensitized human blood basophils in the presence and absence of allergen using a basophil activation test, and to inhibit allergen binding to specific IgE on a rat basophilic cell line stably expressing human FcεRI. RESULTS: IgG autoantibodies binding to both free and FcεRI-bound IgE were detected in patients with atopic and non-atopic asthma, as well as controls. While some were able to activate IgE-sensitised basophils, others inhibited allergen-induced basophil activation, at least partly by inhibiting binding of IgE to specific allergen. CONCLUSION: Naturally occurring IgG anti-IgE autoantibodies may inhibit, as well as induce, basophil activation. They act in a manner distinct from therapeutic IgG anti-IgE antibodies such as omalizumab. They may at least partly explain why atopic subjects who make allergen-specific IgE never develop clinical symptoms, and why omalizumab therapy is of variable clinical benefit in severe atopic asthma.

Systematic care for asthma in Australian general practice: a randomised controlled trial.

OBJECTIVE: To evaluate whether systematic asthma care involving a register-recall system, postcard prompts for review, and education for general practitioners and staff in Australian general practice improves the quality of care and health outcomes for adult patients with moderate to severe asthma. DESIGN AND SETTING: Cluster randomised controlled trial in 40 general practices in urban and rural South Australia and New South Wales over the 2 years 2004 and 2005; practices were randomly allocated to the intervention or control group. PARTICIPANTS: 565 adult patients of these randomly allocated practices who had doctor-diagnosed moderate to severe asthma and were taking inhaled corticosteroids. MAIN OUTCOME MEASURES: Clinical asthma indicators, quality of care, acceptability of the intervention to patients, quality of life, and asthma self-management skills at baseline, 6 months and 12 months. RESULTS: Although 46% of patients in the intervention group practices responded to the postcard prompts, only 32% actually attended for their asthma review. At 12 months, there was a statistically significant difference in provision of written asthma action plans (rate ratio, 1.9; 95% CI, 1.0-3.5; P = 0.04) for intervention group patients compared with control group patients; there was no significant difference in other indicators. CONCLUSION: We found little objective evidence of improvement in patient management and outcomes resulting from a systematic model of asthma care. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12605000091606.