Production and characterization of antibodies reactive with leukotoxin.

A sensitive radioimmunoassay was developed for the determination of leukotoxin (9: 10-epoxy-12-octadecenoic acid), which was reported to exist in human burned skin and neutrophils, and was regarded as a toxic and/or defensive substance in living beings. The leukotoxin was conjugated with bovine serum albumin by means of the mixed anhydride technique as immunogen and rabbits were immunized over 4 months. According to a titration test of antiserum, forty-fold diluted antiserum was found to bind approximately 50% of about 4,000 dpm of methylated leukotoxin labeled with [14C] carbon. The detection limit of leukotoxin was at least as low as 5 ng in this radioimmunoassay by use of a polyetylene glycol precipitation method. This antiserum had a strong specificity to leukotoxin and no cross-reactivity with the other analogs tested.