Analysis of antigenic determinants in cholera enterotoxin and heat-labile enterotoxins from human and porcine enterotoxigenic Escherichia coli

Abstract

Antigenic determinants of cholera enterotoxin (CT) and heat-labile enterotoxin from a human strain (LT(h)) and a porcine strain (LT(p)) were analyzed by Ouchterlony double-gel diffusion test against anti-CT, and anti-LT(h), and anti-LT(p), which were treated by immunoaffinity column chromatography. The results showed the existence of the following antigenic determinants: (i) antigenic determinants unique to CT, LT(h), and LT(p), respectively; (ii) an antigenic determinant common to CT, LT(h), and LT(p); (iii) an antigenic determinant common to CT and LT(h), but not LT(p); and (iv) an antigenic determinant common to LH(h) and LT(p), but not CT. On the basis of these results, an antigenic scheme for CT, LT(h), and LT(p) is proposed.