An ELISA for recombinant Lepidoglyphus destructor, Lep d 2, and the monitoring of exposure to dust mite allergens in farming households.
BACKGROUND
Exposure to indoor allergens, such as dust mites, has been recognized as a risk factor for sensitization and symptoms.


OBJECTIVE
To develop a two-site ELISA for the determination of Lep d 2 in the reservoir, to measure dust mite allergen exposure (Lep d 2, Der p 1, Der f 1 and Der 2) in farm households, and to investigate whether exposure to these allergens is associated with sensitization, asthma and rhinoconjunctivitis.


METHODS
Monoclonal antibodies to recombinant (r)Lep d 2 were produced with standard hybridoma technique. Dust samples from 393 households were analysed for allergen content by two-site ELISA methods.


RESULTS
A two-site Lep d 2 ELISA was developed with a detection limit of 0.09 microg/g. The assay was highly reproducible and levels of Lep d 2 showed a strong correlation with the number of Lepidoglyphus mites (r(s): 0.7; P = 0.0002). Lep d 2 was detected in 20% of the homes; levels ranged from 0.09 to 1.7 microg/g of dust. Der p 1 was recorded in 59% of the samples, ranging from 0.055 to 139 microg/g, and Der f 1 and Der 2 in 40% and 50% of the samples, ranging from 0.055 to 24.5 microg/g and 24.3 microg/g, respectively. Dermatophagoides allergens were significantly higher in mattresses than in carpets (P < 0.0001), but this difference was not observed with Lep d 2. A strong relationship between immunoglobulin (Ig)E to rLep d 2 and asthma (OR = 10.4) and rhinoconjunctivitis (OR = 7.5) was seen. Furthermore, sensitization to D. pteronyssinus was significantly associated with asthma (OR: 13.7) and rhinoconjunctivitis (OR: 5.7).


CONCLUSIONS
When assessing mite allergen exposure in rural homes, not only the Der p 1, Der f 1 and Der 2 allergens, but also the Lep d 2 allergen should be taken into consideration.
Parvaneh
S
S
Department of Medicine, Karolinska, Institutet and Hospital, Stockholm, Sweden.
Johansson
E
E
Elfman
L H M
LH
van Hage-Hamsten
M
M
D000383:Agriculture; D000485:Allergens / Q000032:analysis*; D000818:Animals; D001249:Asthma / Q000209:etiology; D001512:Bedding and Linens; D003231:Conjunctivitis / Q000209:etiology; D004391:Dust; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006798:Housing; D006801:Humans; D006967:Hypersensitivity / Q000150:complications; D008925:Mites / Q000276:immunology*; D011994:Recombinant Proteins / Q000032:analysis; D012220:Rhinitis / Q000209:etiology
D000485:Allergens; D004391:Dust; C422452:Lep d 7 allergen; D011994:Recombinant Proteins