Mites and house dust allergy

Abstract

Summary House dust and mite ( Dermatophagoides pteronyssinus and D. farinae ) dialysed extracts were fractionated by gel filtration and ion‐exchange chromatography. The protein and sugar content of each fraction was determined, respectively, by absorbance at 280 mμ and by the orcinol method. Pooled fractions were injected into house dust and mite sensitive patients and their capacity to induce positive skin reactions determined. A certain amount of allergenically active material was dialysable but the greater part remained inside the dialysis bag. The most active non‐dialysable house dust and mite extract material was eluted in the excluded Sephadex G‐50 fractions and appeared to be located immediately after the Sephadex G‐75 excluded fractions. On the basis of calibration curves, its molecular weight was estimated between 10,000 and 50,000. By further chromatography of active Sephadex fractions on DEAE‐Sephadex, the most potent antigen‐containing material of house dust and mite extracts was recovered using 0‐3 and 02 M NaC1 as elution media. These data offer further evidence of the existence of a close relationship between the major antigenic substances of house dust and mite extracts.