Population Growth and Allergen Content of Cultured <b><i>Euroglyphus maynei</i></b> House Dust Mites

Abstract

Background: The house dust mite, Euroglyphus maynei, occurs in homes worldwide and is an important source of many allergens. Many patients sensitive to Dermatophagoides farinae and D. pteronyssinus are also sensitive to E. maynei. Extracts to detect sensitivity to E. maynei and reagents to detect E. maynei allergens in the environment or in cultures are not readily available. Information for the culture of E. maynei and for the determination of allergen and endotoxin levels in cultures is limited. Method: We mass cultured E. maynei at 23 and 30°C and determined the population growth profiles from inoculation until cultures could be harvested for the production of extracts. We also developed an ELISA to measure Eur m 1 and Eur m 2 allergens using mouse monoclonal antibodies directed at cross-reacting epitopes of group 1 and group 2 allergens of D. farinae and D. pteronyssinus. Results: The E. maynei populations grew exponentially at both 23 and 30°C; however, the cultures matured more rapidly at 23°C. The Eur m 1 and Eur m 2 allergen concentrations in culture extracts changed independently as the cultures grew and matured. At both temperatures, the Eur m 1 concentrations increased as the cultures matured, while the Eur m 2 concentrations did not. The endotoxin levels in these cultures were low. Conclusion: We report here that E. maynei can be cultured at 23 and 30°C. Monoclonal antibodies directed at cross-reacting epitopes on Dermatophagoides allergens can be used to measure the associated E. maynei allergen levels in these cultures.

Proteome, Allergenome, and Novel Allergens of House Dust Mite, Dermatophagoides farinae

“…Mite-rearing condition in our system is under the temperature in range of 25–30 °C with 75–80% humidity. With the indicated ambient, mite population becomes mature in approximately 4–6 weeks, which is rather shorter when compared with those of the conditions in the western countries. − It has been documented that maximum growth phase provides not only the highest amount of live mites but also the allergen concentration, , and hence we use mature mites for source of material for allergenic extract.…”

“…On the contrary, Der f 10, which was minor allergen among the Korean patients, gave IgE binding to sera of 75% of the 20 Thai patients. Several publications reported that the culturing temperature and culture media influences the rate of mite-population growth, allergen production, and the ratio of allergens in extracts made from cultured mites. − ,, This might explain the dissimilar results and immuno-proteomics. Moreover, identification and characterization of HDM allergens using new approaches like genomic and transcriptomic techniques could reveal 20 canonical allergens and 7 noncanonical allergen homologues including novel allergen, ubiquinol-cytochrome c reductase binding protein-like protein designated Der f 24 .…”

Allergen homologs in the Euroglyphus maynei draft genome

“…The strain of E . maynei that was chosen for genome sequencing is a long-standing laboratory reference culture that originated in Galveston, TX, USA, and has been maintained as a randomly-breeding population for over 20 years [ 5 , 20 ]. Genomic DNA was isolated from a pool of living mites (~20 mg wet weight) using the Wizard SV genomic DNA purification system (Promega, Madison, WI) and the manufacturer’s animal tissue protocol.…”