DETECTION OF STAPHYLOCOCCAL-ENTEROTOXIN-H BY AN ENZYME-LINKED-IMMUNOSORBENT-ASSAY

A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) w as developed for the detection of a newly identified staphylococcal en terotoxin H (SEH). Peroxidase was conjugated to antibodies specific to the enterotoxin. 2,2'Azino-bis(3-ethylbenz-thiazoline-6-sulfonic acid )(ABTS) in hydrogen peroxide solution was used as the enzyme substrate . A standard curve of purified SEH was prepared with concentrations ra nging from 1.3 to 50 ng/ml. SEH at levels equal to 2.5 ng/ml and highe r were detected by this procedure. Culture supernatant from the growth of selected Staphylococcus aureus strains was analyzed by using the E LISA. SEH was produced by three of 20 strains that produced one identi fied enterotoxin. Ten of 21 strains, previously shown to produce subst ances that induced emesis in monkeys but not any known enterotoxins (A through E), were also positive for SEH production. The other 11 strai ns gave negative results in the ELISA, indicating that other unidentif ied serological types of enterotoxin exist.