F18ac fimbriae (F18ac)

F18ac fimbriae are proteinaceous surface appendages found on specific strains of enterotoxigenic Escherichia coli (ETEC) that primarily affect swine (PMID: 1550500). These fimbriae are composed of a major subunit, FedA, and a tip adhesin, FedF, which facilitates the attachment of the bacteria to the brush border of porcine enterocytes (UniProt: P24207). This adherence is a prerequisite for the colonization of the small intestine and the subsequent release of enterotoxins, leading to post-weaning diarrhea (PWD) (PMID: 21844312). Because the F18ac variant is highly prevalent in ETEC strains causing significant economic impact in the swine industry, it serves as a critical target for veterinary interventions. Current therapeutic approaches include the use of live-attenuated oral vaccines, such as Coliprotec F18, to stimulate local intestinal immunity and the development of anti-adhesive molecules that block the binding of FedF to host carbohydrate receptors (PMID: 25108000).

Other names

F18 fimbriaeFed fimbriae2134P fimbriae8813 fimbriaeF18ac adhesin

Inhibition of bacterial adhesion to intestinal epithelial cells and induction of mucosal immunity through active or passive immunization.