Enterotoxigenic Escherichia coli heat-labile enterotoxin B subunit (LTB) (LTB)

The Enterotoxigenic Escherichia coli (ETEC) heat-labile enterotoxin B subunit (LTB) is a non-toxic, pentameric protein that serves as the binding component of the LT enterotoxin, a major virulence factor in ETEC infections (UniProt: P06717). LTB functions by specifically recognizing and binding to GM1 ganglioside receptors on the surface of intestinal epithelial cells, which facilitates the entry of the enzymatic A subunit into the cell (PubMed: 25633414). This binding event is a critical step in the pathogenesis of traveler's diarrhea, as it leads to the activation of adenylate cyclase and subsequent fluid secretion. Due to its high immunogenicity and ability to elicit a strong mucosal immune response, LTB is a primary target for vaccine development (PubMed: 30243717). Vaccines targeting LTB, such as ETVAX, aim to generate neutralizing secretory IgA antibodies that block the toxin's attachment to the intestinal wall. Furthermore, LTB is frequently utilized as a potent mucosal adjuvant in various vaccine formulations to enhance the immune response to other antigens.

Other names

Heat-labile enterotoxin subunit BLT-BETEC LTBE. coli heat-labile enterotoxin B subunitLTB antigenEnterotoxigenic Escherichia coli heat-labile enterotoxin B subunit – mimicked antigen

Induction of neutralizing antibodies, primarily secretory IgA (sIgA), that competitively inhibit the binding of the heat-labile enterotoxin to GM1 ganglioside receptors on the intestinal epithelium, thereby preventing toxin internalization and subsequent diarrhea (PubMed: 30243717).