Allergens of the house dust mite Dermatophagoides farinae--immunochemical studies of four allergenic fractions.

Analysis of the allergenic components of the house dust mite Dermatophagoides farinae was performed. Four different types of proteins reactive with human anti-mite IgE antibodies were identified as four distinct radioprecipitins in radioimmunoelectrophoresis. These were designated as mite allergen reactive with human IgE antibodies (Me) Me 1, Me 2, Me 3, and Me 4 according to their electrophoretic mobility from the slower to the faster. Me 1 and Me 2 were the first and the second prevailing allergens, respectively, in 133 atopic patients subjected to the study. Me 1, on purification by gel filtration and anion exchange chromatography, elicited a single radioprecipitin by radioimmunoelectrophoresis. Me 1 also elicited a single band in sodium dodecyl sulphate-polyacrylamide gel electrophoresis and a single peak in high-performance liquid chromatography. Both methods elicited identical values of 17,000 daltons for the molecular weight of Me 1. The isoelectric point of Me 1 was suggested to be 8.0. Me 1 elicited higher skin reactions compared to that obtained by the crude mite extract when it was assessed in seven atopic patients by serial titration intradermal skin testing.