Clinico-Immunochemical Studies on Airborne <i>Areca catechu</i> L. Pollen, a Probable Risk Factor in Emergency Asthma Hospitalization from Eastern India

Abstract

Background: The pollen grain of the Areca catechu L. tree is airborne and allergenic. This study aimed to know the role of this pollen as a source of aeroallergen with effect on emergency asthma hospitalization, to isolate its important allergic fraction and to check its cross-reaction with betel nut. Methods:Areca pollen was monitored with a Burkard sampler. Determination of allergenic activities was studied by in vivo and in vitro analyses. Asthma hospitalization data were collected from two nearby hospitals. The pollen extract was fractionated by a combination of DEAE-Sephadex and Sephacryl S-200 column. The protein components were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cross-reactivity of Areca pollen and betel nut was shown by IgE enzyme-linked immunosorbent assay (ELISA) inhibition. Results: The Areca pollen was perennially airborne. Skin test results of respiratory allergic patients showed 38.6% positivity. The detected aeroallergen spots in particle immunoblotting correlated significantly with airborne pollen count. Areca pollen showed a significant positive correlation with asthma hospitalization. There are 6 IgE-reactive protein components in the whole-pollen extract. IgE-reactive fraction 1 was resolved into 4 subfractions. Subfraction 1a showing IgE reactivity contained 3 protein components, among which 2 of 48 and 118 kDa were IgE reactive. The 48-kDa component was reported to be cross-reactive with other palm pollen types. In IgE ELISA inhibition, the betel nut extract showed 50% inhibition with about 110 ng/ml concentration. Conclusion:A. catechu pollen is a significant contributor to the aeroallergen load in India. Its partially purified IgE-reactive fraction may be useful in therapeutics. The betel nut extract showed remarkable cross-reactivity with Areca pollen.

Betel Chewing and Arecoline Affects Eotaxin-1, Asthma and Lung Function

“…To date, few epidemiological studies have investigated the potential effect of betel chewing on the susceptibility to asthma and impairment of lung function, and these studies have suffered from relatively small sample sizes [10], [19]. The underlying mechanism that drives the proposed relationship between betel chewing and asthma is also still unclear.…”

Primary Identification, Biochemical Characterization, and Immunologic Properties of the Allergenic Pollen Cyclophilin Cat r 1

“…The result was expressed as values obtained using patient serum/average OD value obtained using normal control sera (P/N values). Total IgE values of all sera were estimated using the Pathozyme total IgE quantification kit (Omega Diagnostics, Alva, UK), as described previously (29).…”

“…ELISA inhibition was done to assess cross-reactivity between Cat r 1 and fugal Cyp allergens as described elsewhere (28,29).…”

Spectrum of Allergens and Allergen Biology in India

“…The extract was fractionated into an ion exchange and gel filtration column to separate the IgE-reactive components. Two IgE-binding proteins with a molecular weight of 48 kDa and 118 kDa were obtained in a particular fraction, and the 48-kDa allergen was found to be cross-reactive with other palm allergens [62]. Interestingly, certain pollen allergens were also observed to cross-react with the extract of betel nut fruit extract.…”