Erratum to: “Adjuvant effect of Gantrez® AN nanoparticles during oral vaccination of piglets against F4+enterotoxigenic Escherichia coli”

EnterotoxigenicEscherichia coli(ETEC) strains are a common cause of diarrhea. Extraordinary antigenic diversity has prompted a search for conserved antigens to complement canonical approaches to ETEC vaccine development. EtpA, an immunogenic extracellular ETEC adhesin relatively conserved in the ETEC pathovar, has previously been shown to be a protective antigen following intranasal immunization. These studies were undertaken to explore alternative routes of EtpA vaccination that would permit use of a double mutant (R192G L211A) heat-labile toxin (dmLT) adjuvant. Here, oral vaccination with EtpA adjuvanted with dmLT afforded significant protection against small intestinal colonization, and the degree of protection correlated with fecal IgG, IgA, or total fecal antibody responses to EtpA. Sublingual vaccination yielded compartmentalized mucosal immune responses with significant increases in anti-EtpA fecal IgG and IgA, and mice vaccinated via this route were also protected against colonization. In contrast, while intradermal (i.d.) vaccination achieved high levels of both serum and fecal antibodies against both EtpA and dmLT, mice vaccinated via the i.d. route were not protected against subsequent colonization and the avidity of serum IgG and IgA EtpA-specific antibodies was significantly lower after i.d. immunization compared to other routes. Finally, we demonstrate that antiserum from vaccinated mice significantly impairs binding of LT to cognate GM1 receptors and shows near complete neutralization of toxin delivery by ETECin vitro. Collectively, these data provide further evidence that EtpA could complement future vaccine strategies but also suggest that additional effort will be required to optimize its use as a protective immunogen.

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Protective Immunity Against Enterotoxigenic Escherichia coli by Oral Vaccination of Engineered Lactococcus lactis

Current Microbiology ◽

10.1007/s00284-021-02601-x ◽

2021 ◽

Author(s):

Homa Ahmadi Rouzbahani ◽

Seyed Latif Mousavi Gargari ◽

Shahram Nazarian ◽

Sajad Abdollahi

Keyword(s):

Escherichia Coli ◽

Lactococcus Lactis ◽

Protective Immunity ◽

Enterotoxigenic Escherichia Coli ◽

Oral Vaccination

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Alleviation of enterotoxigenic Escherichia coli challenge by recombinant Lactobacillus plantarum expressing a FaeG- and DC-targeting peptide fusion protein

Beneficial Microbes ◽

10.3920/bm2016.0116 ◽

2017 ◽

Vol 8 (3) ◽

pp. 379-391 ◽

Cited By ~ 10

Author(s):

G. Yang ◽

Y. Jiang ◽

P. Tong ◽

C. Li ◽

W. Yang ◽

...

Keyword(s):

Escherichia Coli ◽

Lactobacillus Plantarum ◽

Body Weight Gain ◽

Immunoglobulin A ◽

Enterotoxigenic Escherichia Coli ◽

Oral Vaccination ◽

Beneficial Effects ◽

Targeting Peptide ◽

Spleen And Lymph Nodes ◽

K88 Fimbriae

FaeG is the major subunit of K88 fimbriae. These cell surface attachments are considered to be the major virulence factor of enterotoxigenic Escherichia coli (ETEC), which causes diarrhoea in piglets. The use of dendritic cell-targeting peptide (DCpep) has been demonstrated to be an effective approach to enhance the immunity of vaccines. Lactobacillus plantarum is an attractive candidate for oral vaccination owing to its beneficial effects and safety. In this study, L. plantarum was employed to deliver a FaeG-DCpep fusion antigen, and the immune response in mice was evaluated. The synthesis of FaeG-DCpep dramatically increased the adhesion of recombinant L. plantarum (RLP) to IPEC-J2 cell surfaces, resulting in direct competition between L. plantarum and ETEC during adhesion assays. Significantly higher levels of body weight gain, sera immunoglobulin G and intestinal immunoglobulin A were observed in BALB/c mice immunised with RLP. In addition, the number of CD19+ B cells and CD11c+DC cells and the expression levels of several cytokines in the spleen and lymph nodes increased significantly compared to non-immunised mice. The oral administration of RLP also alleviated the symptoms of ETEC challenge, as shown by haematoxylin-eosin staining, indicating that RLP may be an efficient vaccine candidate.

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Host-specific fimbrial adhesins of noninvasive enterotoxigenic Escherichia coli strains.

Microbiological Reviews ◽

10.1128/mr.46.2.129-161.1982 ◽

1982 ◽

Vol 46 (2) ◽

pp. 129-161 ◽

Cited By ~ 4

Author(s):

W Gaastra ◽

F K de Graaf

Keyword(s):

Escherichia Coli ◽

Enterotoxigenic Escherichia Coli ◽

Fimbrial Adhesins

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Structure of the master regulator Rns reveals an inhibitor of enterotoxigenic Escherichia coli virulence regulons

Scientific Reports ◽

10.1038/s41598-021-95123-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Charles R. Midgett ◽

Kacey Marie Talbot ◽

Jessica L. Day ◽

George P. Munson ◽

F. Jon Kull

Keyword(s):

Escherichia Coli ◽

Small Molecules ◽

Family Member ◽

Shigella Flexneri ◽

Decanoic Acid ◽

Enterotoxigenic Escherichia Coli ◽

Gram Negative Bacteria ◽

Enteric Infections ◽

First Time ◽

Arac Family

AbstractEnteric infections caused by the gram-negative bacteria enterotoxigenic Escherichia coli (ETEC), Vibrio cholerae, Shigella flexneri, and Salmonella enterica are among the most common and affect billions of people each year. These bacteria control expression of virulence factors using a network of transcriptional regulators, some of which are modulated by small molecules as has been shown for ToxT, an AraC family member from V. cholerae. In ETEC the expression of many types of adhesive pili is dependent upon the AraC family member Rns. We present here the 3 Å crystal structure of Rns and show it closely resembles ToxT. Rns crystallized as a dimer via an interface similar to that observed in other dimeric AraC’s. Furthermore, the structure of Rns revealed the presence of a ligand, decanoic acid, that inhibits its activity in a manner similar to the fatty acid mediated inhibition observed for ToxT and the S. enterica homologue HilD. Together, these results support our hypothesis that fatty acids regulate virulence controlling AraC family members in a common manner across a number of enteric pathogens. Furthermore, for the first time this work identifies a small molecule capable of inhibiting the ETEC Rns regulon, providing a basis for development of therapeutics against this deadly human pathogen.

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