Enzyme-linked immunosorbent assay for Escherichia coli heat-stable enterotoxin type II

Abstract

The gene for Escherichia coli heat-stable enterotoxin type II (ST(II)) was fused to the genes for protein A from Staphylococcus aureus and β-galactosidase in two different expression systems. Antibodies raised in rabbits against the protein A-ST(II) fusion protein recognized the β-galactosidase-ST(II) fusion protein. The latter fusion protein was used as the immobilized antigen in an enzyme-linked immunosorbent assay (ELISA) for detection of ST(II). The correlation between the results of the ELISA and the intestinal loop test in piglets was 95%, suggesting that the ELISA can be used to reliably detect ST(II).