The decay of house dust mite allergens, Der p I and Der p II, under natural conditions.
BACKGROUND
Fluctuations in the level of mite allergens in domestic house dust are the result of changes in the balance between synthesis, removal and decay. Purely physical forces as well as enzymatic degradation, mediated by house dust inhabiting microbes, may contribute to the decay of allergens in domestic dust. Knowledge about the speed of decay is essential for an understanding of the dynamics of allergen levels.


OBJECTIVE
The present study is a quantitative assessment of the speed of decay at nine combinations of temperature (15 degrees C, 20 degrees C and 25 degrees C) and relative humidity (33%, 55% and 75%).


METHODS
Samples of mite infested material of an old rug were stored at these temperature/relative humidity-combinations for 6, 12 or 18 months, after the mites were killed by either a freezing treatment or an acaricide (lindane). The microbes living in the rug presumably survive these treatments. Concentrations of Der p I and Der p II + Der f II, in extracts of the rug material, were measured by radio immunoassay.


RESULTS
No significant changes in the levels of der p I and Der p II + Der f II, could be detected even after 1 1/2 year at a high temperature and humidity.


CONCLUSIONS
These findings indicate that mite allergens can be extremely stable under normal domestic circumstances.
de Boer
R
R
Department of Pure and Applied Ecology, University of Amsterdam, The Netherlands.
van der Hoeven
W A
WA
Stapel
S O
SO
D000485:Allergens / Q000276:immunology*; D000818:Animals; D039741:Antigens, Dermatophagoides; D005615:Freezing; D006023:Glycoproteins / Q000737:chemistry*; D006813:Humidity; D008925:Mites / Q000276:immunology*; D013696:Temperature; D013997:Time Factors
D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins