Antibodies to intimin and Escherichia coli secreted proteins A and B in patients with enterohemorrhagic Escherichia coli infections

Abstract

Enterohemorrhagic Escherichia coli produce an attaching and effacing lesion upon adhering to the intestinal epithelium. Bacterial factors involved in this histopathology include the intimin adhesin and E. coli secreted proteins (Esps) A and B. In this study we investigated the serum antibody responses to recombinant E. coli O157:H7 intimin, EspA, and EspB by immunoblotting. Canadian patients with O157:H7 infection (n=10), Swedish patients with O157:H7 (n=21), non-O157 (n=18), or infection from which the serotype was not available (n=3), and asymptomatic household members (n=25) were studied and compared with Canadian (n=20) and Swedish controls (n=52). In Canadian patients, IgG antibodies to intimin, EspA, and EspB were analyzed, in Swedish patients and their household members IgA, IgG, and IgM antibodies to EspA and EspB were studied. Patients and household members mounted an antibody response to the antigens. Significantly more patients developed an acute response to EspB compared with controls (P<0.01 Canadian patients, P<0.0001 Swedish patients). EspB IgA, IgG, and IgM had a specificity of 100%, 86%, and 86%, positive predictive value of 100%, 83%, and 81%, and sensitivity of 57%, 69%, and 63%, respectively, and appear to be an appropriate assay for the detection of EHEC infection. In cases of hemolytic uremic syndrome or hemorrhagic colitis this assay may be useful when a fecal strain has not been isolated, or in epidemics of non-O157 infection.

Bovine Colostrum Contains Immunoglobulin G Antibodies against Intimin, EspA, and EspB and Inhibits Hemolytic Activity Mediated by the Type Three Secretion System of Attaching and Effacing Escherichia coli

“…The immunogenicity of the LEE-encoded proteins studied here was also observed in patients infected with E. coli O157:H7 or other EHEC serotypes, as well as in their household contacts (13,18) or children with EPEC-associated diarrhea (23). Furthermore, several studies have shown that colostrum and milk from healthy women from both industrialized and developing countries contain IgA antibodies reactive to the LEE-encoded proteins (20,22,30,33).…”

Use of In Vivo-Induced Antigen Technology for Identification of Escherichia coli O157:H7 Proteins Expressed during Human Infection

“…Pooled unadsorbed HUS convalescent-phase sera reacted strongly and specifically with E. coli XL1-Blue(pEB313) (35) and E. coli DH5␣(pCVD468, pREP4) (22), expressing His 6 -intimin-␥ and His 6 -EspA, respectively, in contrast to E. coli BL21(DE3) expressing recombinant Vibrio cholerae PilA, an irrelevant control protein (Fig. 1A).…”

“…1B). Since both are reportedly expressed during human infection (22,29), as well as during in vitro growth (36), we anticipated reactivity with both might be eliminated by adsorption of the sera. We attribute the residual serum reactivity with intimin-␥ to relatively weak in vitro expression of this protein, which may be insufficient to adsorb away all of the anti-intimin-␥ antibodies generated in response Screening of an E. coli O157 genomic expression library.…”

Cross-Reactive Protection against Enterohemorrhagic Escherichia coli Infection by Enteropathogenic E. coli in a Mouse Model

“…Bands were detected at approximately 94 kDa and 37 kDa, corresponding to intimin and EspB, respectively (Fig. 4, lanes 1 and 2) (27). No bands were visualized for sera taken from mice in the PBS/EHEC group (n ϭ 2) before FIG.…”

“…EPEC or EHEC infections (11,27,31). It has been suggested that these antibodies could confer protection against subsequent EPEC infection.…”