A Lactococcus lactis-vectored oral vaccine induces protective immunity of mice against enterotoxigenic Escherichia coli lethal challenge

ABSTRACT Enterotoxigenic Escherichia coli (ETEC) diarrheal disease is a worldwide problem that may be addressed by transcutaneous delivery of a vaccine. In several human settings, protective immunity has been associated with immune responses to E. coli colonization factors and to the heat-labile toxin that induces the diarrhea. In this set of animal studies, transcutaneous immunization (TCI) using recombinant colonization factor CS6 and cholera toxin (CT) or heat-labile enterotoxin (LT) as the adjuvant induced immunoglobulin G (IgG) and IgA anti-CS6 responses in sera and stools and antibody responses that recognized CS6 antigen in its native configuration. The antitoxin immunity induced by TCI was also shown to protect against enteric toxin challenge. Although immunization with LT via the skin induced mucosal secretory IgA responses to LT, protection could also be achieved by intravenous injection of the immune sera. Finally, a malaria vaccine antigen, merzoite surface protein 142 administered with CT as the adjuvant, induced both merzoite surface protein antibodies and T-cell responses while conferring protective antitoxin immunity, suggesting that both antiparasitic activity and antidiarrheal activity can be obtained with a single vaccine formulation. Overall, our results demonstrate that relevant colonization factor and antitoxin immunity can be induced by TCI and suggest that an ETEC traveler's diarrhea vaccine could be delivered by using a patch.

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Oral Immunization with a Salmonella typhimurium Vaccine Vector Expressing Recombinant Enterotoxigenic Escherichia coli K99 Fimbriae Elicits Elevated Antibody Titers for Protective Immunity

Infection and Immunity ◽

10.1128/iai.66.11.5470-5476.1998 ◽

1998 ◽

Vol 66 (11) ◽

pp. 5470-5476 ◽

Cited By ~ 50

Author(s):

Miguel A. Ascón ◽

David M. Hone ◽

Nancy Walters ◽

David W. Pascual

Keyword(s):

Escherichia Coli ◽

Salmonella Typhimurium ◽

Protective Immunity ◽

Mononuclear Cells ◽

Immunoglobulin A ◽

Oral Immunization ◽

Enterotoxigenic Escherichia Coli ◽

Effective Vaccine ◽

Antibody Titers ◽

And Control

ABSTRACT Bovine enterotoxigenic Escherichia coli (ETEC) continues to cause mortality in piglets and newborn calves. In an effort to develop a safe and effective vaccine for the prevention of F5+ ETEC infections, a balanced lethalasd + plasmid carrying the complete K99 operon was constructed and designated pMAK99-asd +. Introduction of this plasmid into an attenuated Salmonella typhimurium Δaro Δasd strain, H683, resulted in strain AP112, which stably expresses E. coli K99 fimbriae. A single oral immunization of BALB/c and CD-1 mice with strain AP112 elicited significant mucosal immunoglobulin A (IgA) titers that remained elevated for >11 weeks. IgA and IgG responses in serum specific for K99 fimbriae were also induced, with a prominent IgG1, as well as IgG2a and IgG2b, titer. To assess the derivation of these antibodies, a K99 isotype-specific B-cell ELISPOT analysis was conducted by using mononuclear cells from the lamina propria of the small intestines (LP), Peyer’s patches (PP), and spleens of vaccinated and control BALB/c mice. This analysis revealed elevated numbers of K99 fimbria-specific IgA-producing cells in the LP, PP, and spleen, whereas elevated K99 fimbria-specific IgG-producing cells were detected only in the PP and spleen. These antibodies were important for protective immunity. One-day-old neonates from dams orally immunized with AP112 were provided passive protection against oral challenge with wild-type ETEC, in contrast to challenged neonates from unvaccinated dams or from dams vaccinated with a control Salmonella vector. These results confirm that oral Salmonella vaccine vectors effectively deliver K99 fimbriae to mucosal inductive sites for sustained elevation of IgA and IgG antibodies and for eliciting protective immunity.

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Protective effects of selenium nanoparticle-enriched Lactococcus lactis NZ9000 against enterotoxigenic Escherichia coli K88-induced intestinal barrier damage in mice

Applied and Environmental Microbiology ◽

10.1128/aem.01636-21 ◽

2021 ◽

Author(s):

Yue Chen ◽

Lei Qiao ◽

Xiaofan Song ◽

Li Ma ◽

Xina Dou ◽

...

Keyword(s):

Escherichia Coli ◽

Lactococcus Lactis ◽

Sodium Selenite ◽

Low Cost ◽

Intestinal Barrier ◽

Feed Additives ◽

Enterotoxigenic Escherichia Coli ◽

Protective Effects ◽

Barrier Dysfunction ◽

Wide Range

Composite microecological agents have received widespread attention due to their advantageous properties, including safety, multi-effects, and low cost. This study was conducted to evaluate the protective effects of selenium (Se) nanoparticle-enriched Lactococcus lactis NZ9000 ( L. lactis NZ9000-SeNPs) against enterotoxigenic Escherichia coli K88 (ETEC K88)-induced intestinal barrier damage in C57BL/6 mice. Oral administration of L. lactis NZ9000-SeNPs significantly increased the villi height and the number of goblet cells in the ileum, and reduced the levels of serum and ileal interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ), and increased the activities of thioredoxin reductase (TrxR) and glutathione peroxidase (GSH-Px) compared with the ETEC K88-infected group not treated with L. lactis NZ9000-SeNPs. In addition, L. lactis NZ9000-SeNPs significantly attenuated the reduction of the expression levels of occludin and claudin-1, dysbiosis of the gut microbiome, and the activation of toll-like receptor (TLR)/nuclear factor-kappa (NF-κB)-mediated signaling pathway induced by ETEC K88. These findings suggested that L. lactis NZ9000-SeNPs may be a promising and safe Se supplement for food or feed additives. Importance The beneficial effects of microecological agents have been widely proven. Se, which is nutritionally essential trace element for human and animals, is incorporated into selenoproteins that have a wide range of pleiotropic effects, ranging from antioxidant and anti-inflammatory effects. However, the sodium selenite, a common addition form of Se in feed and food, has disadvantages such as strong toxicity and low bioavailability. We investigated the protective effects of L. lactis NZ9000-SeNPs against ETEC K88-induced intestinal barrier injury in C57BL/6 mice. Our results show that L. lactis NZ9000-SeNPs effectively alleviate ETEC-K88-induced intestinal barrier dysfunction. This study highlights the importance of developing a promising and safe Se supplement for the substation of sodium selenite applied in food, feed and biomedicine.

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Protective immunity of a Multivalent Vaccine Candidate against piglet diarrhea caused by enterotoxigenic Escherichia coli (ETEC) in a pig model

Vaccine ◽

10.1016/j.vaccine.2017.12.026 ◽

2018 ◽

Vol 36 (5) ◽

pp. 723-728 ◽

Cited By ~ 17

Author(s):

Henghui Zhang ◽

Yongping Xu ◽

Zhijun Zhang ◽

Jiansong You ◽

Yanyong Yang ◽

...

Keyword(s):

Escherichia Coli ◽

Protective Immunity ◽

Vaccine Candidate ◽

Pig Model ◽

Enterotoxigenic Escherichia Coli ◽

Multivalent Vaccine

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Efficacy of thiolated eudragit microspheres as an oral vaccine delivery system to induce mucosal immunity against enterotoxigenic Escherichia coli in mice

European Journal of Pharmaceutics and Biopharmaceutics ◽

10.1016/j.ejpb.2012.01.010 ◽

2012 ◽

Vol 81 (1) ◽

pp. 43-48 ◽

Cited By ~ 11

Author(s):

Won-Jung Lee ◽

Seungbin Cha ◽

Minkyoung Shin ◽

Myunghwan Jung ◽

Mohammad Ariful Islam ◽

...

Keyword(s):

Escherichia Coli ◽

Delivery System ◽

Mucosal Immunity ◽

Oral Vaccine ◽

Vaccine Delivery ◽

Enterotoxigenic Escherichia Coli ◽

Vaccine Delivery System

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Genotypic characterization of Egypt enterotoxigenic Escherichia coli isolates expressing coli surface antigen 6

The Journal of Infection in Developing Countries ◽

10.3855/jidc.2454 ◽

2013 ◽

Vol 7 (02) ◽

pp. 090-100 ◽

Cited By ~ 2

Author(s):

Atef M El-Gendy ◽

Adel Mansour ◽

Hind I Shaheen ◽

Marshall R Monteville ◽

Adam W Armstrong ◽

...

Keyword(s):

Escherichia Coli ◽

Surface Antigen ◽

Protective Immunity ◽

Surface Antigens ◽

Enterotoxigenic Escherichia Coli ◽

Mechanisms Of Resistance ◽

E Coli ◽

Colonization Factor ◽

Factor Expression

Introduction: One approach to control enterotoxigenic Escherichia coli (ETEC) infections has been to develop vaccines focused on inducing protective immunity against surface expressed antigenic factors. One such factor is coli surface antigen 6 (CS6); ETEC isolates expressing CS6 may also simultaneously co-express surface antigens CS4 or CS5. However, there is little information regarding the inter-relationships of isolates expressing the CS6 antigen alone or in combination with CS4 or CS5. Methodology: A total of 62 CS6-associated ETEC isolates were evaluated for their antimicrobial susceptibility, mechanisms of resistance, toxin genes, colonization factor expression, and XbaI-pulsed-field gel electrophoretic profiles. Results: We observed 46 XbaI profiles; 31 were exclusive to ETEC expressing CS6 alone and 15 among the ETEC co-expressing CS4 or CS5. Nearly half (47%) of these isolates were resistant to ampicillin, a third (37%) of the isolates were resistant to trimethoprim-sulfamethoxazole, and 24% of the isolates were tetracycline-resistant. A blaTEM gene was detected in 24 (83%) ampicillin-resistant isolates. Trimethoprim-sulfamethoxazole-resistant isolates (n = 23) carried either sulI (n = 1, 4%), sulII (n = 8, 35%) or both genes (n = 10, 43%); 4 had no detectable sul gene. Conclusions: Our results show a lack of clonality among Egypt CS6 E. coli isolates and supports the use and the further research on vaccines targeting this cell surface antigen.

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Attenuated Shigella flexneri 2a Vaccine Strain CVD 1204 Expressing Colonization Factor Antigen I and Mutant Heat-Labile Enterotoxin of Enterotoxigenic Escherichia coli

Infection and Immunity ◽

10.1128/iai.68.9.4884-4892.2000 ◽

2000 ◽

Vol 68 (9) ◽

pp. 4884-4892 ◽

Cited By ~ 44

Author(s):

Hilary Koprowski ◽

Myron M. Levine ◽

Richard J. Anderson ◽

Genevieve Losonsky ◽

Mariagrazia Pizza ◽

...

Keyword(s):

Escherichia Coli ◽

Vaccine Strain ◽

Guinea Pigs ◽

Oral Vaccine ◽

Shigella Flexneri ◽

Surface Expression ◽

Enterotoxigenic Escherichia Coli ◽

Secretory Iga ◽

Colonization Factor ◽

Heat Labile

ABSTRACT A multivalent live oral vaccine against both Shigellaspp. and enterotoxigenic Escherichia coli (ETEC) is being developed based on the hypothesis that protection can be achieved if attenuated shigellae express ETEC fimbrial colonization factors and genetically detoxified heat-labile toxin from a human ETEC isolate (LTh). Two detoxified derivatives of LTh, LThK63 and LThR72, were engineered by substitution—serine to lysine at residue 63, or lysine to arginine at residue 72. The genes encoding these two derivatives were cloned separately on expression plasmids downstream from the CFA/I operon. Following electroporation into S. flexneri 2a vaccine strain CVD 1204, coexpression of CFA/I and LThK63 or LThR72 was demonstrated by Western blot analysis, GM1 binding assays, and agglutination with anti-CFA/I antiserum. Hemagglutination and electron microscopy confirmed surface expression of CFA/I. Guinea pigs immunized intranasally on days 0 and 15 with CVD 1204 expressing CFA/I and LThK63 or LThR72 exhibited high titers of both serum immunoglobulin G (IgG) and mucosal secretory IgA anti-CFA/I; 40% of the animals produced antibodies directed against LTh. All immunized guinea pigs also produced mucosal IgA (in tears) and serum IgG anti-S. flexneri 2a O antibodies. Furthermore, all immunized animals were protected from challenge with wild-type S. flexneri 2a. This prototype Shigella-ETEC hybrid vaccine demonstrates the feasibility of expressing multiple ETEC antigens on a single plasmid in an attenuated Shigella vaccine strain and engendering immune responses against both the heterologous antigens and vector strain.

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