Immunobiochemical characterization of Brassica campestris pollen allergen

Brassica campestris (BC), Eng. Mustard, is an important source of pollen allergen, responsible for type I hypersensitivity disorders. In the present study, BC pollen extract was characterized by TLIEF, SDS-PAGE and immunoprinting. The extract separated into 50 silver stained bands of pI 3-9 on isoelectric focusing whereas it resolved into 14 Coomassie blue stained protein bands of 14-100 kD on SDS-PAGE. Immunoblot analysis with individual patient sera detected four allergenic proteins of 90, 67, 60 and 14 kD. BC separated into 8 peaks (Bras 1-8) on DEAE Sephadex A-50 column. Bras 2 was found to be most potent by IgE specific ELISA, hence further fractionated on Sephadex G-200. A protein of 90 kD (Bras 2a) isolated by gel filtration was found to be most allergenic protein by ELISA inhibition. The findings shall be applicable in standardization of future batches of BC pollen extract to be used for allergy diagnosis and immunotherapy.