Enzymatic analyses of house dust mite extracts from Dermatophagoides pteronyssinus and Dermatophagoides farinae (Acari: Pyroglyphidae) during different phases of culture growth

摘要

The majority of clinically important allergens of D. pteronyssinus and D. farinae present enzymatic activity. The allergenic enzymes described include cysteine proteinases in group 1 allergens, trypsins in group 3, amylases in group 4 and chymotrypsins in group 6. Apart from these, other possibly allergenic enzymes also have been identified. Enzymatic profiles were studied during the 3 growth periods of the mite population - latency phase, exponential growth phase and death phase. The activity of 19 different enzymes was analysed by means of the Api Zym system, a method that has been used to study both mite extracts and other allergenic materials. This study demonstrated that the extracts contain a large variety of enzymes. Enzymatic activity wascaused exclusively by mites, because the control carried out on the culture medium was negative for all the enzymes studied. Generally, the levels of diverse enzymatic activity increased with the growth of the culture, and decreased later, in both species. However, proteinases are the exception; they maintain a high level of activity during the death phase of the cultured mites. The ratio between trypsin and chymotrypsin activity can be used as an excellent tool for quality control parameters during obtention of allergenic mite extracts.