Uropathogenic Escherichia coli antigens (UPEC antigens) (UPEC antigens)

Uropathogenic Escherichia coli (UPEC) antigens are a diverse group of surface-exposed and secreted molecules that enable the bacteria to colonize the urinary tract and cause infection (Nature Reviews Microbiology, 2015). Key antigens include adhesins like FimH (type 1 fimbriae) and PapG (P fimbriae), which facilitate attachment to bladder and kidney cells, respectively (Journal of Molecular Biology, 2017). Other important antigens include the H-antigen (flagella), O-antigen (lipopolysaccharide), and various iron-acquisition proteins like IroN and aerobactin (Infection and Immunity, 2012). These antigens are primary targets for the development of vaccines, such as the O-antigen conjugate vaccine ExPEC9V, and anti-adhesive therapies like FimH inhibitors (e.g., GSK3882347) aimed at preventing recurrent urinary tract infections (Lancet Infectious Diseases, 2020; ClinicalTrials.gov, 2023). By targeting these specific virulence factors, researchers hope to provide alternatives to traditional antibiotics, thereby reducing the risk of antimicrobial resistance and preserving the host's commensal microbiota (Frontiers in Cellular and Infection Microbiology, 2021). The diversity of UPEC strains presents a challenge for broad-spectrum vaccine efficacy, necessitating the inclusion of multiple conserved or prevalent antigens in therapeutic formulations. Successful targeting of these antigens can prevent the formation of intracellular bacterial communities (IBCs), which are often responsible for the persistence and recurrence of UTIs.

Other names

UPEC virulence factorsExtraintestinal pathogenic Escherichia coli antigensExPEC antigensUrinary tract infection E. coli antigens

Vaccines induce protective immune responses, including systemic IgG and mucosal secretory IgA, against specific bacterial surface components to prevent colonization and invasion (Lancet Infectious Diseases, 2020). Small molecule inhibitors, such as FimH antagonists, competitively bind to the lectin domain of bacterial adhesins to block their attachment to mannosylated host urothelial receptors (Nature Communications, 2017).