Colonization factor antigen CS1 (CS1) (CS1)

Colonization factor antigen CS1 (CS1) is a fimbrial adhesin expressed on the surface of Enterotoxigenic Escherichia coli (ETEC), which is a leading cause of diarrhea in children in low-income countries and travelers (Qadri et al., 2005). CS1 is part of the CFA/II complex and is assembled through the chaperone-usher pathway, primarily composed of the major subunit CooA (UniProt P02971). Its primary biological function is to mediate the attachment of the bacteria to the small intestinal mucosa, allowing for colonization and the subsequent release of heat-labile (LT) and heat-stable (ST) toxins (Wolf, 1997). Because of its critical role in pathogenesis, CS1 is a primary component in several ETEC vaccine candidates, including the oral inactivated vaccine ETVAX (Lundgren et al., 2014). Therapeutic strategies targeting CS1 focus on inducing mucosal IgA antibodies that sterically hinder bacterial docking to host receptors, thereby preventing infection (Svennerholm, 2011).

Other names

CS1 fimbriaeCooACFA/II componentColonization factor CS1

Induction of mucosal IgA antibodies to block bacterial adhesion to intestinal epithelial cells