THIOPHILIC ADSORPTION CHROMATOGRAPHY - PURIFICATION OF EQU C2 AND EQUC3, 2 HORSE ALLERGENS FROM HORSE SWEAT

Purification of two allergens from horse (Equus caballus) sweat, Equ c 2 and Equ c3, by means of salt-promoted chromatography on a ''thiophil ic'' (T-gel) adsorbent is described. Immobilization of these proteins was found to be dependent on the presence of water-structure-forming s alts where the ammonium sulphate concentration in the equilibration bu ffer was 2 M. Equ c2 showed higher affinity towards the thiophilic mat rix than Equ c3. Their molecular mass (M,) values established by SDS-p olyacrylamide gel electrophoresis were for Equ c2 approximate to 17 00 0 and for Equ c3 approximate to 16 000, and both proteins showed a low isoelectric point of approximate to 3.8. Their allergenic properties were also investigated using sera from horse-sensitized patients, wher e it was demonstrated that these proteins exhibited an IgE antibody bi nding capacity. In this report we show the broad potential application s of thiophilic adsorption chromatography for the efficient purificati on of allergens. (C) 1998 Elsevier Science B.V. All rights reserved.