Basophil kallikrein of anaphylaxis (BK-A)--purification and characterization.

: These studies describe the IgE-mediated release of a basophil kallikrein of anaphylaxis (BK-A) that has arginine esterase activity and is inhibited by plasma, DFP, and Trasylol. The interaction of BK-A active fractions from ion exchange (DEAE-Sephacel) and gel filtration (Sepharose 6B) chromatography, with human plasma kininogen generates immunoreactive kinin. The BK-A and kinin-generating activities co-chromatograph on DEAE-Sephacel and Sepharose 6B columns, and the quantity of kinin generated is, in general, proportional to the BK-A activity of the column fractions, suggesting that these two activities are subserved by the same protease. These data suggest that kallikrein-like activity can be generated from human basophils as a direct result of a primary IgE-mediated immune reaction, thus providing a potential link between reactions of immediate hypersensitivity and the plasma and/or tissue kinin-generating systems.