Urinary concentrations of 15-epimer of lipoxin A(4) are lower in patients with aspirin-intolerant compared with aspirin-tolerant asthma.

BACKGROUND: Although an abnormality in arachidonic acid metabolism may be responsible for aspirin-intolerant asthma (AIA), there is little knowledge about the concentrations of urinary lipoxin A(4) (LXA(4)) and the 15-epimer of LXA(4) (15-epi-LXA(4)) in relation to asthma severity in AIA subjects. OBJECTIVE: The purpose of this study is to estimate urinary LXA(4) and the 15-epimer concentrations to investigate lipoxins in AIA. METHODS: In this study, we examined AIA, aspirin-tolerant asthma (ATA) and healthy control groups. The AIA and ATA groups were subdivided into the severe asthma and non-severe asthma subgroups. Urinary LXA(4), 15-epi-LXA(4) and leukotriene E(4) (LTE(4) ) were quantified using enzyme immunoassay after separating these compounds using high-performance liquid chromatography. RESULTS: The urinary LXA(4) concentration was significantly lower than the 15-epi-LXA(4) concentration in the asthmatic subjects. The AIA group showed significantly lower urinary 15-epi-LXA(4) (P < 0.01) and higher urinary LTE(4) concentrations (P < 0.05) than the ATA group. Comparison of 15-epi-LXA(4) concentrations between the severe asthmatic and non-severe asthmatic subjects in the AIA and ATA groups revealed that the decreased 15-epi-LXA(4) concentration may be related to aspirin intolerance, but not asthma severity. Receiver operator characteristic curves demonstrated that the concentration ratio of LTE(4) to 15-epi-LXA(4) was superior to 15-epi-LXA(4) concentration and LTE(4) concentration as a predictive factor for aspirin intolerance. CONCLUSIONS AND CLINICAL RELEVANCE: We have demonstrated for the first time that urinary 15-epi-LXA(4) concentration is significantly higher than LXA(4) concentration in both the AIA and ATA groups. 15-Epi-LXA(4) concentration was significantly lower in the AIA group with an increased urinary LTE(4) concentration than in the ATA group. An imbalance between proinflammatory cysteinyl-leukotrienes and anti-inflammatory 15-epi-LXA(4) may be involved in AIA pathogenesis.

[Evaluation of MAST-26, newly developed system for the detection of IgE antibodies].

MAST-26 is a new allergy testing system which allows simultaneous determination of allergen-specific IgE antibody levels for 26 allergens using 200 microliters of patient serum. To evaluate the effectiveness of MAST-26 for the detection of allergen-specific IgE antibody, a total of 100 serum samples were collected from allergic patients at five facilities, and allergen-specific IgE antibody was measured by MAST-26. 14% of them were positive to > or = 10 allergens. If the patients had severe allergic symptoms, they were likely to show positive to many allergens. A good correlation was found between the results obtained by MAST-26 with those measured by CAP RAST and by intradermal skin test. It was concluded that MAST-26 is an effective screening method for the detection of allergen-specific IgE.

IgE antibodies against midge and moth found in Japanese asthmatic subjects and comparison of allergenicity between these insects.

The specific IgE antibodies to moth (Bombyx mori) and midge (Chironomus yoshimatsui) were measured by the Pharmacia CAP system in 51 house-dust-mite-sensitive asthma patients. None of these patients had definite histories of exposure to these insects or apparent evidence of insect-induced asthma symptoms. The RAST-inhibition assay was performed to investigate cross-allergenicity between these two insects. Furthermore, IgE immunoblotting was done to study the IgE-binding components in moth and midge extracts. Thirty (59%) of these patients showed positive IgE antibodies to moth, while 25 (49%) showed positive IgE antibodies to midge. Those frequencies of positivity were similar to that for Japanese cedar pollen, which is well known to cause allergy. A significant correlation (r = 0.863) was observed between IgE antibody titers of these two insects. The results from the RAST-inhibition assay indicated cross-allergenicity between these insects and also the existence of species-specific allergens. Fifteen IgE-binding components in moth extract were observed. The most frequent IgE-binding protein was the 79-kDa (84.2%), followed by the 72-kDa (78.9%), the 82-kDa (57.9%), and the 76-kDa (57.9%) proteins. Those were considered to be major allergens in moth. Twenty-four IgE-binding components in midge extract were observed. However, no IgE-binding protein to which over 50% of patient sera reacted was observed. These results suggest that these two insects may be considered to bear important allergens and that there is cross-allergenicity between these insects as well as species-specific allergens.

[Airway responsiveness measured by body plethysmograph connecting a circuit of an inhalation system of serially concentrated bronchoconstrictant].

We developed a new methodology to examine the bronchial response to the bronchoconstrictants, acetylcholine and methacholine. An inhalation device was connected to the body plethysmograph circuit so that a minute inhalation of serially concentrated bronchoconstrictant could be quickly switched to the circuit of the measurement of the airway resistance. The following were calculated: airway responsiveness in terms of sensitivity, provocative dose to increase the airway resistance up to 35% from the baseline. PC35 or PD35 and the reactivity, the slope of the declining specific airway conductance and %delta SGaw. The airway responsiveness was examined in asthmatics, COPD outgrew -childhood asthma patients and normal subjects. These three groups were categorised differently from each other in both sensitivity and reactivity.