Performance of EAST in diagnosing inhalant allergens in children with allergic rhinitis

The performance of enzyme linked immunosorbent assays (EAST) for identifying six indoor allergens was evaluated using skin prick test (SPT) as reference tests in 154 children with allergic rhinitis. Sensitivity of EAST ranged from 9% (cat) to 54% (HDM) with specificity of 74%(cockroach) to 100% (cat) with an agreement ranged from 58 to 86%. Cut off values ?> ?0.35 kU/L showed best sensitivity and specificity. Our findings agree with extant literature which suggests that the ability of EAST to determine the precipitating allergen is moderate. Assays for definitively identifying the inhalant allergen are currently not available.     

OX40 blockade inhibits house dust mite driven allergic lung inflammation in mice and in vitro allergic responses in humans

The costimulatory receptor OX40 is expressed on activated T cells and regulates T‐cell responses. Here, we show the efficacy and mechanism of action of an OX40 blocking antibody using the chronic house dust mite (HDM) mouse model of lung inflammation and in vitro HDM stimulation of cells from HDM allergic human donors. We have demonstrated that OX40 blockade leads to a reduction in the number of eosinophils and neutrophils in the lavage fluid and lung tissue of HDM sensitized mice. This was accompanied by a decrease in activated and memory CD4⁺ T cells in the lungs and further analysis revealed that both the Th2 and Th17 populations were inhibited. Improved lung function and decreased HDM‐specific antibody responses were also noted. Significantly, efficacy was observed even when anti‐OX40 treatment was delayed until after inflammation was established. OX40 blockade also inhibited the release of the Th2 cytokines IL‐5 and IL‐13 from cells isolated from HDM allergic human donors. Altogether, our data provide evidence of a role of the OX40/OX40L pathway in ongoing allergic lung inflammation and support clinical studies of a blocking OX40 antibody in Th2 high severe asthma patients.     

Profiles of IgE Sensitization to Der f 1, Der f 2, Der f 6, Der f 8, Der f 10, and Der f 20 in Korean House Dust Mite Allergy Patients

Purpose

Measurement of IgE specific to purified house dust mite (HDM) allergens may improve allergy diagnosis. This study aimed to investigate the sensitization profiles of Korean HDM allergic subjects suffering from respiratory allergy and atopic dermatitis (AD) to Der f 1, Der f 2, Der f 6, Der f 8, Der f 10, and Der f 20.

Methods

Recombinant HDM allergens were produced in Pichia pastoris (Der f 1) or Escherichia coli (5 allergens). IgE reactivity to the individual recombinant allergens and total extract of mite was assessed by ELISA.

Results

Der f 1 was recognized by 79.1%, Der f 2 by 79.1%, Der f 6 by 9.3%, Der f 8 by 6.2%, Der f 10 by 6.2%, and Der f 20 by 6.6% of the patients'' sera tested, while the prevalence of IgE reactivity to total mite extract was 94.7%. Combination of Der f 1 and Der f 2 had a sensitivity of 87.6%. Specific IgE to Der f 2 alone was detected from 89.4% of HDM-sensitized respiratory allergy subjects and 92.3% to the combination of the 2 major allergens Der f 1 and Der f 2. However, sera from fewer patients with AD, namely 72.4% and 71.0%, recognized Der f 1 and Der f 2, respectively. The combination of 2 major allergens allowed diagnosis of 84.5% of the AD patients. No correlation between sensitization to specific allergens and HDM allergy entity was found.

Conclusions

Der f 2 was the most frequently sensitized allergen among the HDM-sensitized respiratory and AD patients in Korea, and the combination of the group 1 and 2 major allergens increased the diagnostic sensitivity. Minor allergens did not significantly improve diagnostic sensitivity. However, further studies are needed to analyze the relationship between sensitization to other HDM allergens and the disease entity of the HDM allergy.     

A reintroduction of environmental mite allergen control strategies for asthma treatment and the debate on their effectiveness

Asthma affects three hundred million people worldwide. The effectiveness of house dust mite allergen control for asthma treatment is debatable. One aspect that has been little discussed in existing meta‐analyses is the possible role of environmental strategies. Here, we reintroduce the previously defined strategies for mite allergen control and discuss their importance to the debate on clinical effectiveness. The strategy of concurrent bedroom interventions is related to the combined use of a priori defined interventions, while the strategy of exposure‐based control relates to the treatment of relevant textiles after assessing exposure. The air purification strategy aims to purify the human breathing zone of airborne allergens. In Western European patient practice, the use of these strategies differs. A post hoc study of the dominant Cochrane review by Gøtzsche and Johansen (Cochrane Database of Systematic Reviews, 2008, Art. No: CD001187) appears to indicate that a majority of the underlying trials reported on the strategy of concurrent bedroom interventions, which were mainly executed in a minimal manner. Some trials have reported on the air purification strategy and may potentially alter the debate on effectiveness. No trial has reported on the strategy of exposure‐based control. We therefore hypothesize that the absence of evidence for the effectiveness of mite allergen control for asthma treatment applies to the strategy of concurrent bedroom interventions. The evidence‐based effectiveness of the exposure‐based control strategy appears to be undetermined. The results of our post hoc reanalysis urge that future meta‐analyses of mite allergen control should a priori define the environmental strategy under study. Future trials of mite allergen control are warranted to test the exposure‐based strategy as well as the sparsely tested strategy of air purification.