Allergen Resource Guide - Hitachi Chemical Diagnostics

Resource Guide to the Most Common Allergens
Common Name: Mite
Latin Names: 1- Dermatophagoides pteronyssinus (D1)
2- Dermatophagoides farinae (D2)
Description: House dust mites of the genus Dermatophagoides are associated with
symptoms of asthma and rhinitis. Three species, D. pteronyssinus,
D. farinea and D. microceras are recognized as important allergen
sources in house dust.
Allergenic proteins of mites (with molecular weight):
Mite Allergens MW (kDa) Function IgE binding frequency (% sera)
Der 1 25 cysteine protease 80 - 100
Der 2 14 probably lysozyme 80 - 100
Der 3 28 - 30 Trypsin 70 - 100
Der 4 60 Amylase 40
Der 5 14 40
Der 6 25 Chymotrypsin 40
Der 7 22, 26, 28 40
Der 8 Glutathione transferase N/A
Der 9 Collagenolytic serine prot. N/A
Der 10 36 Tropomyosin N/A
Der 14 Apolipophorin like protein N/A
However, the most commonly and strongly bound allergens are Group I and Group II.
1-Group I of major mite allergens have been isolated, which includes Der p 1, Der f 1
and Der m 1. These allergens have the same MW (24 kDa) and are structurally
homologous. The cDNA and sequence analyses suggest that group I allergens are
proteases. These proteins are heat labile and pH sensitive and predominantly extracted
in mite feces.
2-Group II of major allergens are Der p 2, Der f 2 and Der m 2 with the MW of 14 to 15
kDa. In contrast with Group I allergens, Group II proteins are heat stable and pH
resistant and their physiological function is unknown. Studies showed Group I (25 kDa)
found 32 times more than Group II in mite feces. The ratio of Group I to the Group II in
the air is about 1.5:1 and in dust is 2:1. Group I allergens from dust mites only become
airborne during disturbance and fall rapidly; which is in keeping with their being carried
on fecal pellets.
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