Potent immunogenicity of the B subunits of Escherichia coli heat-labile enterotoxin: receptor binding is essential and induces differential modulation of lymphocyte subsets

A study was conducted on receptor binding in the potent immunogenicity of Escherichia coli heat-labile enterotoxin B subunit (EtxB) in vivo and in vitro in primed B and T cells. EtxB was compared with the receptor-binding mutant EtxB(G33D), where aspartate was substituted for glycine at residue 33. Results showed that the mutation Gly-33 - Asp triggered a significant reduction in the ability of EtxB to bind GM1 ganglioside.