Shiga toxin-producing Escherichia coli surface antigens and Shiga toxins (STEC antigens and toxins)

Shiga toxin-producing Escherichia coli (STEC) surface antigens and Shiga toxins (Stx1 and Stx2) are the primary virulence factors responsible for severe foodborne illnesses, including hemorrhagic colitis and the life-threatening hemolytic uremic syndrome (HUS) (CDC, 2023) [1]. The Shiga toxins are AB5-type holotoxins that enter host cells via the globotriaosylceramide (Gb3) receptor and inhibit protein synthesis by cleaving the 28S ribosomal RNA, leading to cell death (UniProt, 2024) [2]. Surface antigens, such as intimin and various O-antigens (e.g., O157), facilitate the initial attachment and colonization of the intestinal epithelium (StatPearls, 2023) [3]. Therapeutic strategies targeting these components include monoclonal antibodies, such as Urtoxazumab and Shigamabs, designed to neutralize the toxins in the bloodstream and prevent their systemic effects (Lopez et al., 2010) [4]. Additionally, small molecule inhibitors and polymeric decoys like Synsorb Pk have been explored to block toxin binding to host receptors or to inhibit the bacterial adhesion process (PubMed, 2015) [5]. Because traditional antibiotic treatment can trigger a stress response in the bacteria that increases toxin production, direct targeting of the toxins and surface antigens represents a critical alternative for managing STEC infections (NIH, 2022) [6]. These targets are essential for the pathogenesis of STEC and are the focus of diagnostic and therapeutic development to prevent the progression to HUS.

Other names

VerocytotoxinShiga-like toxinStxVTEC antigensEHEC virulence factorsStx1Stx2IntiminO-antigen

The primary mechanism of action for drugs targeting these molecules involves the neutralization of Shiga toxins (Stx1 and Stx2) to prevent their binding to the host cell receptor Gb3, thereby halting the inhibition of protein synthesis and subsequent cell death (UniProt, 2024) [2]. Additionally, agents targeting surface antigens aim to block bacterial adhesion to the intestinal mucosa, preventing colonization and the delivery of toxins to the host (StatPearls, 2023) [3].