Studies on the physicochemical properties of house dust mite (Dermatophagoides pteronyssinus) allergens involved in reaginic reaction.

The physicochemical nature of the allergenic component of Dermatophagoides pteronyssinus extract was studied by gel filtration, ion exchange chromatography, isoelectrofocusing, and polyacrylamide gel electrophoresis. Fractions were assayed for allergenic activity by the direct radioallergosorbent test (RAST) (dilution method), RAST inhibition (50% inhibition method) and human skin testing. Fractions were further studied by preparative polyacrylamide gel electrophoresis and the band showing a flow rate value of 0.35 was the most potent in allergenic activity. Fractionation by isoelectrofocusing yielded three factions with allergenic activity of pI = 4.8, PI = 7.4 and pI = 10.0 Sephadex G-100 gel filtration revealed that allergenic activity was present in fractions with molecular weight ranging from 17,000-45,000 and discrete ion exchange chromatography evidenced three fractions with very high allergenic activity. In the present study we propose that the allergenic material of D.P is composed of 3 physicochemically different substances whose molecular weight lie in the 17,000 to 45,000 range.