1
|
Srivastava R, González-Prieto C, Lynch JP, Muscolo M, Lin CY, Brown MA, Lemos L, Shrestha A, Osburne MS, Leong JM, Lesser CF. In situ deposition of nanobodies by an engineered commensal microbe promotes survival in a mouse model of enterohemorrhagic E. coli. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.30.605899. [PMID: 39131305 PMCID: PMC11312530 DOI: 10.1101/2024.07.30.605899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Engineered smart microbes that deliver therapeutic payloads are emerging as treatment modalities, particularly for diseases with links to the gastrointestinal tract. Enterohemorrhagic E coli (EHEC) is a causative agent of potentially lethal hemolytic uremic syndrome. Given concerns that antibiotic treatment increases EHEC production of Shiga toxin (Stx), which is responsible for systemic disease, novel remedies are needed. EHEC encodes a type III secretion system (T3SS) that injects Tir into enterocytes. Tir inserts into the host cell membrane, exposing an extracellular domain that subsequently binds intimin, one of its outer membrane proteins, triggering the formation of attaching and effacing (A/E) lesions that promote EHEC mucosal colonization. Citrobacter rodentium (Cr), a natural A/E mouse pathogen, similarly requires Tir and intimin for its pathogenesis. Mice infected with Cr(ΦStx2dact), a variant lysogenized with an EHEC-derived phage that produces Stx2dact, develop intestinal A/E lesions and toxin-dependent disease. Stx2a is more closely associated with human disease. By developing an efficient approach to seamlessly modify the C. rodentium genome, we generated Cr_Tir-MEHEC(ΦStx2a), a variant that expresses Stx2a and the EHEC extracellular Tir domain. We found that mouse pre-colonization with HS-PROT3EcT-TD4, a human commensal E. coli strain (E. coli HS) engineered to efficiently secrete- an anti-EHEC Tir nanobody, delayed bacterial colonization and improved survival after challenge with Cr_Tir-MEHEC(ΦStx2a). This study provides the first evidence to support the efficacy of engineered commensal E. coli to intestinally deliver therapeutic payloads that block essential enteric pathogen virulence determinants, a strategy that may serve as an antibiotic-independent antibacterial therapeutic modality.
Collapse
Affiliation(s)
- Rajkamal Srivastava
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Coral González-Prieto
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Jason P Lynch
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Michele Muscolo
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
| | - Catherine Y Lin
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
| | - Markus A Brown
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Luisa Lemos
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
| | - Anishma Shrestha
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - Marcia S Osburne
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
| | - John M Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA
- Tufts Stuart B Levy Center for Integrated Management of Antimicrobial Resistance, Tufts University, Boston, MA, 02111, USA
| | - Cammie F Lesser
- Center for Bacterial Pathogenesis, Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, MA, 02115, USA
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Ragon Institute of Harvard and MIT, Cambridge, MA, 02139, USA
| |
Collapse
|
2
|
Reggi S, Dell'Anno M, Baldi A, Rossi L. Seed-specific expression of porcine verotoxigenic Escherichia coli antigens in tobacco plants as a potential model of edible vaccines. Vet Res Commun 2024; 48:1435-1447. [PMID: 38319502 PMCID: PMC11147939 DOI: 10.1007/s11259-024-10318-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 01/27/2024] [Indexed: 02/07/2024]
Abstract
Vaccines can reduce the use of antibiotics by preventing specific infective diseases in pigs. Plant-based edible vaccines are particularly attractive because, upon oral ingestion via feed, they can elicit the local immune system against a foreign disease-causing organism. The aim of this study was to engineer two different independent lines of tobacco plants for the seed-specific expression of immunogenic proteins of VTEC as a model of an edible vaccine. For each antigen, fifty Nicotiana tabacum L. cv Xanthi leaf disks were transformed by agroinfection for the seed-specific expression of the structural parts of the fimbrial subunit FedF of F18 and the B-subunit of Vt2e genes. The synthetic genes, optimized by the codon adaptation index for their expression in tobacco, were inserted into expression cassettes under the control of β-conglycinin promoter. Regenerated tobacco plants (T0) were characterized by molecular and immunoenzymatic techniques. Our results showed that both FedF and Vt2eB genes were integrated into tobacco genome efficiently (> 80%) and they are also maintained in the second generation (T1). Western blotting analyses carried out on the positive producing lines, showed the tissue-specific expression in seeds and the temporal protein accumulation in the mid-late maturation phases. The enzyme-linked immunosorbent assay showed seed expression levels of 0.09 to 0.29% (from 138 to 444 µg/g of seeds) and 0.21 to 0.43% (from 321 to 658 µg/g of seeds) of total soluble protein for the FedF and Vt2eB antigens, respectively. This study confirmed the seed-specific expression of the selected antigens in plant seeds. The expression level is suitable for seed-based edible vaccination systems, which could represent a cost-effective way to prevent VTEC infection. Our findings encourage further in vivo studies focused on the activation of the local immune response.
Collapse
Affiliation(s)
- Serena Reggi
- Department of Veterinary Medicine and Animal Sciences - DIVAS, University of Milan, Lodi, 26900, Italy
| | - Matteo Dell'Anno
- Department of Veterinary Medicine and Animal Sciences - DIVAS, University of Milan, Lodi, 26900, Italy
| | - Antonella Baldi
- Department of Veterinary Medicine and Animal Sciences - DIVAS, University of Milan, Lodi, 26900, Italy
| | - Luciana Rossi
- Department of Veterinary Medicine and Animal Sciences - DIVAS, University of Milan, Lodi, 26900, Italy.
| |
Collapse
|
3
|
Liu Y, Lam DMK, Luan M, Zheng W, Ai H. Recent development of oral vaccines (Review). Exp Ther Med 2024; 27:223. [PMID: 38590568 PMCID: PMC11000446 DOI: 10.3892/etm.2024.12511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 02/08/2024] [Indexed: 04/10/2024] Open
Abstract
Oral immunization can elicit an effective immune response and immune tolerance to specific antigens. When compared with the traditional injection route, delivering antigens via the gastrointestinal mucosa offers superior immune effects and compliance, as well as simplicity and convenience, making it a more optimal route for immunization. At present, various oral vaccine delivery systems exist. Certain modified bacteria, such as Salmonella, Escherichia coli and particularly Lactobacillus, are considered promising carriers for oral vaccines. These carriers can significantly enhance immunization efficiency by actively replicating in the intestinal tract following oral administration. The present review provided a discussion of the main mechanisms of oral immunity and the research progress made in the field of oral vaccines. Additionally, it introduced the advantages and disadvantages of the currently more commonly administered injectable COVID-19 vaccines, alongside the latest advancements in this area. Furthermore, recent developments in oral vaccines are summarized, and their potential benefits and side effects are discussed.
Collapse
Affiliation(s)
- Ying Liu
- Key Laboratory of Follicular Development and Reproductive Health in Liaoning Province, Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
| | | | - Mei Luan
- Department of Geriatric Medicine, Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
| | - Wenfu Zheng
- Chinese Academy of Sciences Key Lab for Biological Effects of Nanomaterials and Nanosafety, National Center for NanoScience and Technology, Beijing 100190, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Hao Ai
- Key Laboratory of Follicular Development and Reproductive Health in Liaoning Province, Jinzhou Medical University, Jinzhou, Liaoning 121000, P.R. China
| |
Collapse
|
4
|
Su YL, Larzábal M, Song H, Cheng T, Wang Y, Smith LY, Cataldi AA, Ow DW. Enterohemorrhagic Escherichia coli O157:H7 antigens produced in transgenic lettuce effective as an oral vaccine in mice. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2023; 136:214. [PMID: 37740735 DOI: 10.1007/s00122-023-04460-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 09/07/2023] [Indexed: 09/25/2023]
Abstract
KEY MESSAGE Transgene with recombination sites to address biosafety concerns engineered into lettuce to produce EspB and γ-intimin C280 for oral vaccination against EHEC O157:H7. Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a food-borne pathogen where ruminant farm animals, mainly bovine, serve as reservoirs. Bovine vaccination has been used to prevent disease outbreaks, and the current method relies on vaccines subcutaneously injected three times per year. Since EHEC O157:H7 colonizes mucosal surfaces, an oral vaccine that produces an IgA response could be more convenient. Here, we report on oral vaccination against EHEC O157:H7 in mice orally gavaged with transgenic lettuce that produces EHEC O157:H7 antigens EspB and γ-intimin C280. Younger leaves accumulated a higher concentration of antigens; and in unexpanded leaves of 30-day-old T2 plants, EspB and γ-intimin C280 were up to 32 and 51 μg/g fresh weight, respectively. Mice orally gavaged with lettuce powders containing < 3 µg antigens for 6 days showed a mucosal immune response with reduced colonization of EHEC O157:H7. This suggests that the transgenic lettuce has potential to be used for bovine vaccination. To promote the biosafety of crop plants producing medically relevant proteins, recombination sites were built into our transgenic lines that would permit optional marker removal by Cre-lox recombination, as well as transgene deletion in pollen by CinH-RS2 recombination. The ability to upgrade the transgenic lettuce by stacking additional antigen genes or replacing older genes with newer versions would also be possible through the combined use of Bxb-att and Cre-lox recombination systems.
Collapse
Affiliation(s)
- Yun-Lin Su
- Plant Gene Engineering Center; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China
| | - Mariano Larzábal
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO) INTA-CONICET, Hurlingham, Argentina
| | - Huan Song
- Plant Gene Engineering Center; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China
| | - Tianfang Cheng
- Plant Gene Engineering Center; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China
| | - Yufang Wang
- Plant Gene Engineering Center; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China
| | - Libia Yael Smith
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO) INTA-CONICET, Hurlingham, Argentina
| | - Angel Adrian Cataldi
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO) INTA-CONICET, Hurlingham, Argentina
| | - David W Ow
- Plant Gene Engineering Center; Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement; Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, People's Republic of China.
| |
Collapse
|
5
|
Nakanishi K, Takase T, Ohira Y, Ida R, Mogi N, Kikuchi Y, Matsuda M, Kurohane K, Akimoto Y, Hayakawa J, Kawakami H, Niwa Y, Kobayashi H, Umemoto E, Imai Y. Prevention of Shiga toxin 1-caused colon injury by plant-derived recombinant IgA. Sci Rep 2022; 12:17999. [PMID: 36289440 PMCID: PMC9606113 DOI: 10.1038/s41598-022-22851-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 10/20/2022] [Indexed: 01/24/2023] Open
Abstract
Immunoglobulin A (IgA) is a candidate antibody for oral passive immunization against mucosal pathogens like Shiga toxin-producing Escherichia coli (STEC). We previously established a mouse IgG monoclonal antibody (mAb) neutralizing Shiga toxin 1 (Stx1), a bacterial toxin secreted by STEC. We designed cDNA encoding an anti-Stx1 antibody, in which variable regions were from the IgG mAb and all domains of the heavy chain constant region from a mouse IgA mAb. Considering oral administration, we expressed the cDNA in a plant expression system aiming at the production of enough IgA at low cost. The recombinant-IgA expressed in Arabidopsis thaliana formed the dimeric IgA, bound to the B subunit of Stx1, and neutralized Stx1 toxicity to Vero cells. Colon injury was examined by exposing BALB/c mice to Stx1 via the intrarectal route. Epithelial cell death, loss of crypt and goblet cells from the distal colon were observed by electron microscopy. A loss of secretory granules containing MUC2 mucin and activation of caspase-3 were observed by immunohistochemical methods. Pretreatment of Stx1 with the plant-based recombinant IgA completely suppressed caspase-3 activation and loss of secretory granules. The results indicate that a plant-based recombinant IgA prevented colon damage caused by Stx1 in vivo.
Collapse
Affiliation(s)
- Katsuhiro Nakanishi
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Taichi Takase
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Yuya Ohira
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Ryota Ida
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Noriko Mogi
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Yuki Kikuchi
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Minami Matsuda
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Kohta Kurohane
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Yoshihiro Akimoto
- grid.411205.30000 0000 9340 2869Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, 181-8611 Japan
| | - Junri Hayakawa
- grid.411205.30000 0000 9340 2869Laboratory for Electron Microscopy, Kyorin University School of Medicine, Mitaka, Tokyo, 181-8611 Japan
| | - Hayato Kawakami
- grid.411205.30000 0000 9340 2869Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, 181-8611 Japan
| | - Yasuo Niwa
- grid.469280.10000 0000 9209 9298Laboratory of Plant Molecular Improvement, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Hirokazu Kobayashi
- grid.469280.10000 0000 9209 9298Laboratory of Plant Molecular Improvement, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Eiji Umemoto
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| | - Yasuyuki Imai
- grid.469280.10000 0000 9209 9298Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka 422-8526 Japan
| |
Collapse
|
6
|
Oral Administration with Live Attenuated Citrobacter rodentium Protects Immunocompromised Mice from Lethal Infection. Infect Immun 2022; 90:e0019822. [PMID: 35861565 PMCID: PMC9302154 DOI: 10.1128/iai.00198-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) are important causative agents for foodborne diseases worldwide. Besides antibiotic treatment, vaccination has been deemed as the most effective strategy for preventing EPEC- and EHEC-caused foodborne illnesses. Despite substantial progress made in identifying promising antigens and efficacious vaccines, no vaccines against EPEC or EHEC have yet been licensed. Mice are inherently resistant to EPEC and EHEC infections; infection with Citrobacter rodentium (CR), the murine equivalent of EPEC and EHEC, in mice has been widely used as a model to study bacterial pathogenesis and develop novel vaccine strategies. Mirroring the severe outcomes of EPEC and EHEC infections in immunocompromised populations, immunocompromised mouse strains such as interleukin-22 knockout (Il22-/-) are susceptible to CR infection with severe clinical symptoms and mortality. Live attenuated bacterial vaccine strategies have been scarcely investigated for EPEC and EHEC infections, in particular in immunocompromised populations associated with severe outcomes. Here we examined whether live attenuated CR strain with rational genetic manipulation generates protective immunity against lethal CR infection in the susceptible Il22-/- mice. Our results demonstrate that oral administration of live ΔespFΔushA strain promotes efficient systemic and humoral immunity against a wide range of CR virulence determinants, thus protecting otherwise lethal CR infection, even in immunocompromised Il22-/- mice. This provides a proof of concept of live attenuated vaccination strategy for preventing CR infection in immunocompromised hosts associated with more severe symptoms and lethality.
Collapse
|
7
|
AB 5 Enterotoxin-Mediated Pathogenesis: Perspectives Gleaned from Shiga Toxins. Toxins (Basel) 2022; 14:toxins14010062. [PMID: 35051039 PMCID: PMC8779504 DOI: 10.3390/toxins14010062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023] Open
Abstract
Foodborne diseases affect an estimated 600 million people worldwide annually, with the majority of these illnesses caused by Norovirus, Vibrio, Listeria, Campylobacter, Salmonella, and Escherichia coli. To elicit infections in humans, bacterial pathogens express a combination of virulence factors and toxins. AB5 toxins are an example of such toxins that can cause various clinical manifestations, including dehydration, diarrhea, kidney damage, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Treatment of most bacterial foodborne illnesses consists of fluid replacement and antibiotics. However, antibiotics are not recommended for infections caused by Shiga toxin-producing E. coli (STEC) because of the increased risk of HUS development, although there are conflicting views and results in this regard. Lack of effective treatment strategies for STEC infections pose a public health threat during outbreaks; therefore, the debate on antibiotic use for STEC infections could be further explored, along with investigations into antibiotic alternatives. The overall goal of this review is to provide a succinct summary on the mechanisms of action and the pathogenesis of AB5 and related toxins, as expressed by bacterial foodborne pathogens, with a primary focus on Shiga toxins (Stx). The role of Stx in human STEC disease, detection methodologies, and available treatment options are also briefly discussed.
Collapse
|
8
|
Mühlen S, Dersch P. Treatment Strategies for Infections With Shiga Toxin-Producing Escherichia coli. Front Cell Infect Microbiol 2020; 10:169. [PMID: 32435624 PMCID: PMC7218068 DOI: 10.3389/fcimb.2020.00169] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/31/2020] [Indexed: 01/07/2023] Open
Abstract
Infections with Shiga toxin-producing Escherichia coli (STEC) cause outbreaks of severe diarrheal disease in children and the elderly around the world. The severe complications associated with toxin production and release range from bloody diarrhea and hemorrhagic colitis to hemolytic-uremic syndrome, kidney failure, and neurological issues. As the use of antibiotics for treatment of the infection has long been controversial due to reports that antibiotics may increase the production of Shiga toxin, the recommended therapy today is mainly supportive. In recent years, a variety of alternative treatment approaches such as monoclonal antibodies or antisera directed against Shiga toxin, toxin receptor analogs, and several vaccination strategies have been developed and evaluated in vitro and in animal models. A few strategies have progressed to the clinical trial phase. Here, we review the current understanding of and the progress made in the development of treatment options against STEC infections and discuss their potential.
Collapse
Affiliation(s)
- Sabrina Mühlen
- Institute for Infectiology, University of Münster, Münster, Germany.,German Center for Infection Research (DZIF), Associated Site University of Münster, Münster, Germany
| | - Petra Dersch
- Institute for Infectiology, University of Münster, Münster, Germany.,German Center for Infection Research (DZIF), Associated Site University of Münster, Münster, Germany
| |
Collapse
|
9
|
Joseph A, Cointe A, Mariani Kurkdjian P, Rafat C, Hertig A. Shiga Toxin-Associated Hemolytic Uremic Syndrome: A Narrative Review. Toxins (Basel) 2020; 12:E67. [PMID: 31973203 PMCID: PMC7076748 DOI: 10.3390/toxins12020067] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 01/13/2020] [Accepted: 01/17/2020] [Indexed: 01/28/2023] Open
Abstract
The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.
Collapse
Affiliation(s)
- Adrien Joseph
- Department of Nephrology, AP-HP, Hôpital Tenon, F-75020 Paris, France; (A.J.); (C.R.)
| | - Aurélie Cointe
- Department of Microbiology, AP-HP, Hôpital Robert Debré, F-75019 Paris, France; (A.C.); (P.M.K.)
| | | | - Cédric Rafat
- Department of Nephrology, AP-HP, Hôpital Tenon, F-75020 Paris, France; (A.J.); (C.R.)
| | - Alexandre Hertig
- Department of Renal Transplantation, Sorbonne Université, AP-HP, Hôpital Pitié Salpêtrière, F-75013 Paris, France
| |
Collapse
|
10
|
Rojas-Lopez M, Monterio R, Pizza M, Desvaux M, Rosini R. Intestinal Pathogenic Escherichia coli: Insights for Vaccine Development. Front Microbiol 2018; 9:440. [PMID: 29615989 PMCID: PMC5869917 DOI: 10.3389/fmicb.2018.00440] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 02/26/2018] [Indexed: 12/13/2022] Open
Abstract
Diarrheal diseases are one of the major causes of mortality among children under five years old and intestinal pathogenic Escherichia coli (InPEC) plays a role as one of the large causative groups of these infections worldwide. InPECs contribute significantly to the burden of intestinal diseases, which are a critical issue in low- and middle-income countries (Asia, Africa and Latin America). Intestinal pathotypes such as enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC) are mainly endemic in developing countries, while ETEC strains are the major cause of diarrhea in travelers to these countries. On the other hand, enterohemorrhagic E. coli (EHEC) are the cause of large outbreaks around the world, mainly affecting developed countries and responsible for not only diarrheal disease but also severe clinical complications like hemorrhagic colitis and hemolytic uremic syndrome (HUS). Overall, the emergence of antibiotic resistant strains, the annual cost increase in the health care system, the high incidence of traveler diarrhea and the increased number of HUS episodes have raised the need for effective preventive treatments. Although the use of antibiotics is still important in treating such infections, non-antibiotic strategies are either a crucial option to limit the increase in antibiotic resistant strains or absolutely necessary for diseases such as those caused by EHEC infections, for which antibiotic therapies are not recommended. Among non-antibiotic therapies, vaccine development is a strategy of choice but, to date, there is no effective licensed vaccine against InPEC infections. For several years, there has been a sustained effort to identify efficacious vaccine candidates able to reduce the burden of diarrheal disease. The aim of this review is to summarize recent milestones and insights in vaccine development against InPECs.
Collapse
Affiliation(s)
- Maricarmen Rojas-Lopez
- GSK, Siena, Italy.,Institut National de la Recherche Agronomique, Université Clermont Auvergne, UMR454 MEDiS, Clermont-Ferrand, France
| | - Ricardo Monterio
- Institut National de la Recherche Agronomique, Université Clermont Auvergne, UMR454 MEDiS, Clermont-Ferrand, France
| | | | - Mickaël Desvaux
- Institut National de la Recherche Agronomique, Université Clermont Auvergne, UMR454 MEDiS, Clermont-Ferrand, France
| | | |
Collapse
|
11
|
Abstract
Post-infectious hemolytic uremic syndrome (HUS) is caused by specific pathogens in patients with no identifiable HUS-associated genetic mutation or autoantibody. The majority of episodes is due to infections by Shiga toxin (Stx) producing Escherichia coli (STEC). This chapter reviews the epidemiology and pathogenesis of STEC-HUS, including bacterial-derived factors and host responses. STEC disease is characterized by hematological (microangiopathic hemolytic anemia), renal (acute kidney injury) and extrarenal organ involvement. Clinicians should always strive for an etiological diagnosis through the microbiological or molecular identification of Stx-producing bacteria and Stx or, if negative, serological assays. Treatment of STEC-HUS is supportive; more investigations are needed to evaluate the efficacy of putative preventive and therapeutic measures, such as non-phage-inducing antibiotics, volume expansion and anti-complement agents. The outcome of STEC-HUS is generally favorable, but chronic kidney disease, permanent extrarenal, mainly cerebral complication and death (in less than 5 %) occur and long-term follow-up is recommended. The remainder of this chapter highlights rarer forms of (post-infectious) HUS due to S. dysenteriae, S. pneumoniae, influenza A and HIV and discusses potential interactions between these pathogens and the complement system.
Collapse
Affiliation(s)
- Denis F. Geary
- Division of Nephrology, The Hospital for Sick Children, Toronto, Ontario Canada
| | - Franz Schaefer
- Division of Pediatric Nephrology, University of Heidelberg, Heidelberg, Germany
| |
Collapse
|
12
|
A potential therapeutic peptide-based neutralizer that potently inhibits Shiga toxin 2 in vitro and in vivo. Sci Rep 2016; 6:21837. [PMID: 26903273 PMCID: PMC4763182 DOI: 10.1038/srep21837] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 01/25/2016] [Indexed: 11/08/2022] Open
Abstract
Shiga toxin 2 (Stx2) is a major virulence factor in infections with Stx-producing Escherichia coli (STEC), which can cause serious clinical complications in humans, such as hemolytic uremic syndrome (HUS). Recently, we screened and identified two peptide-based Stx2 neutralizers, TF-1 and WA-8, which specifically and directly bind to Stx2. Computer simulations suggested that the majority of TF-1 or WA-8 binds tightly at the receptor-binding site 3 of Stx2. The two peptides also effectively inhibited the cytotoxic activity of Stx2 by blocking the binding of Stx2 to target cells. TF-1 exhibits remarkable therapeutic potency in both mice and rat toxicity models. In mice toxicity models, TF-1 provided full protection when mice were injected with 5 LD50 of Stx2. In rat toxicity models, TF-1 reduced fatal tissue damage and completely protected rats from the lethal challenges of Stx2. In these rats, TF-1 significantly decreased the concentration of Stx2 in blood and diminished tissue distribution levels of Stx2. Furthermore, TF-1 effectively protected rats from the pathological effects caused by Stx2, especially in the kidney, thymus, adrenal gland, and lung. Taken together, these results indicate that TF-1 is a promising therapeutic agent against the pathogenicity of Stx2.
Collapse
|
13
|
Rahal EA, Fadlallah SM, Nassar FJ, Kazzi N, Matar GM. Approaches to treatment of emerging Shiga toxin-producing Escherichia coli infections highlighting the O104:H4 serotype. Front Cell Infect Microbiol 2015; 5:24. [PMID: 25853096 PMCID: PMC4364364 DOI: 10.3389/fcimb.2015.00024] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/04/2015] [Indexed: 11/13/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) are a group of diarrheagenic bacteria associated with foodborne outbreaks. Infection with these agents may result in grave sequelae that include fatality. A large number of STEC serotypes has been identified to date. E. coli serotype O104:H4 is an emerging pathogen responsible for a 2011 outbreak in Europe that resulted in over 4000 infections and 50 deaths. STEC pathogenicity is highly reliant on the production of one or more Shiga toxins that can inhibit protein synthesis in host cells resulting in a cytotoxicity that may affect various organ systems. Antimicrobials are usually avoided in the treatment of STEC infections since they are believed to induce bacterial cell lysis and the release of stored toxins. Some antimicrobials have also been reported to enhance toxin synthesis and production from these organisms. Various groups have attempted alternative treatment approaches including the administration of toxin-directed antibodies, toxin-adsorbing polymers, probiotic agents and natural remedies. The utility of antibiotics in treating STEC infections has also been reconsidered in recent years with certain modalities showing promise.
Collapse
Affiliation(s)
- Elias A Rahal
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Sukayna M Fadlallah
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Farah J Nassar
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Natalie Kazzi
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Ghassan M Matar
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| |
Collapse
|
14
|
Paul M, Ma JKC. Plant-made immunogens and effective delivery strategies. Expert Rev Vaccines 2014; 9:821-33. [DOI: 10.1586/erv.10.88] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
15
|
Karpman D. Management of Shiga toxin-associated Escherichia coli-induced haemolytic uraemic syndrome: randomized clinical trials are needed. Nephrol Dial Transplant 2013; 27:3669-74. [PMID: 23114892 PMCID: PMC3484732 DOI: 10.1093/ndt/gfs456] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Diana Karpman
- Correspondence and offprint requests to: Diana Karpman; E-mail:
| |
Collapse
|
16
|
Salyaev RK, Rekoslavskaya NI, Stolbikov AS, Tret'yakova AV. Candidate mucosal vaccine against hepatitis B based on tomatoes transgenic for the preS2-S gene. DOKL BIOCHEM BIOPHYS 2012; 446:257-9. [PMID: 23132723 DOI: 10.1134/s1607672912050109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Indexed: 11/23/2022]
Affiliation(s)
- R K Salyaev
- Siberian Institute of Plant Physiology and Biochemistry, Russian Academy of Sciences, Irkutsk, Russia
| | | | | | | |
Collapse
|
17
|
Tellez A, Corredig M, Guri A, Zanabria R, Griffiths M, Delcenserie V. Bovine milk fat globule membrane affects virulence expression in Escherichia coli O157:H7. J Dairy Sci 2012; 95:6313-9. [DOI: 10.3168/jds.2012-5560] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 07/29/2012] [Indexed: 11/19/2022]
|
18
|
Interaction between Shiga toxin and monoclonal antibodies: binding characteristics and in vitro neutralizing abilities. Toxins (Basel) 2012; 4:729-47. [PMID: 23105978 PMCID: PMC3475226 DOI: 10.3390/toxins4090729] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 09/17/2012] [Accepted: 09/17/2012] [Indexed: 11/17/2022] Open
Abstract
Monoclonal antibodies (MAbs) have been employed either for diagnosis or treatment of infections caused by different pathogens. Specifically for Shiga toxin-producing Escherichia coli (STEC), numerous immunoassays have been developed for STEC diagnosis, showing variability in sensitivity and specificity when evaluated by reference laboratories, and no therapy or vaccines are currently approved. Thus, the aim of this work was the characterization of the interaction between MAbs against Stx1 and Stx2 toxins and their neutralizing abilities to enable their use as tools for diagnosis and therapy. The selected clones designated 3E2 (anti-Stx1) and 2E11 (anti-Stx2) were classified as IgG1. 3E2 recognized the B subunit of Stx1 with an affinity constant of 2.5 × 10−10 M, detected as little as 6.2 ng of Stx1 and was stable up to 50 ºC. In contrast, 2E11 recognized the A subunit of Stx2, was stable up to 70 ºC, had a high dissociation constant of 6.1 × 10−10 M, and detected as little as 12.5 ng of Stx2. Neutralization tests showed that 160 ng of 3E2 MAb inhibited 80% of Stx1 activity and 500 µg 2E11 MAb were required for 60% inhibition of Stx2 activity. These MAb amounts reversed 25 to 80% of the cytotoxicity triggered by different STEC isolates. In conclusion, these MAbs show suitable characteristics for their use in STEC diagnosis and encourage future studies to investigate their protective efficacy.
Collapse
|
19
|
Yoshimatsu K, Kawano N, Kawahara N, Akiyama H, Teshima R, Nishijima M. [Current status in the commercialization and application of genetically modified plants and their effects on human and livestock health and phytoremediation]. YAKUGAKU ZASSHI 2012; 132:629-74. [PMID: 22687699 DOI: 10.1248/yakushi.132.629] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Developments in the use of genetically modified plants for human and livestock health and phytoremediation were surveyed using information retrieved from Entrez PubMed, Chemical Abstracts Service, Google, congress abstracts and proceedings of related scientific societies, scientific journals, etc. Information obtained was classified into 8 categories according to the research objective and the usage of the transgenic plants as 1: nutraceuticals (functional foods), 2: oral vaccines, 3: edible curatives, 4: vaccine antigens, 5: therapeutic antibodies, 6: curatives, 7: diagnostic agents and reagents, and 8: phytoremediation. In total, 405 cases were collected from 2006 to 2010. The numbers of cases were 120 for nutraceuticals, 65 for oral vaccines, 25 for edible curatives, 36 for vaccine antigens, 36 for therapeutic antibodies, 76 for curatives, 15 for diagnostic agents and reagents, and 40 for phytoremediation (sum of each cases was 413 because some reports were related to several categories). Nutraceuticals, oral vaccines and curatives were predominant. The most frequently used edible crop was rice (51 cases), and tomato (28 cases), lettuce (22 cases), potato (18 cases), corn (15 cases) followed.
Collapse
Affiliation(s)
- Kayo Yoshimatsu
- Research Center for Medicinal Plant Resources, National Institute of Biomedical Innovation, Ibaraki, Japan.
| | | | | | | | | | | |
Collapse
|
20
|
Goldwater PN, Bettelheim KA. Treatment of enterohemorrhagic Escherichia coli (EHEC) infection and hemolytic uremic syndrome (HUS). BMC Med 2012; 10:12. [PMID: 22300510 PMCID: PMC3286370 DOI: 10.1186/1741-7015-10-12] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 02/02/2012] [Indexed: 11/10/2022] Open
Abstract
Verotoxigenic Escherichia coli (VTEC) are a specialized group of E. coli that can cause severe colonic disease and renal failure. Their pathogenicity derives from virulence factors that enable the bacteria to colonize the colon and deliver extremely powerful toxins known as verotoxins (VT) or Shiga toxins (Stx) to the systemic circulation. The recent devastating E. coli O104:H4 epidemic in Europe has shown how helpless medical professionals are in terms of offering effective therapies. By examining the sources and distribution of these bacteria, and how they cause disease, we will be in a better position to prevent and treat the inevitable future cases of sporadic disease and victims of common source outbreaks. Due to the complexity of pathogenesis, it is likely a multitargeted approach is warranted. Developments in terms of these treatments are discussed.
Collapse
Affiliation(s)
- Paul N Goldwater
- Microbiology and Infectious Diseases, SA Pathology at the Women's and Children's Hospital, and Discipline of Paediatrics, University of Adelaide, 72 King William Road, North Adelaide, South Australia, Australia.
| | | |
Collapse
|
21
|
Vaccination of attenuated EIS-producing Salmonella induces protective immunity against enterohemorrhagic Escherichia coli in mice. Vaccine 2011; 29:7395-403. [DOI: 10.1016/j.vaccine.2011.07.069] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 07/15/2011] [Accepted: 07/17/2011] [Indexed: 01/01/2023]
|
22
|
Human intestinal tissue and cultured colonic cells contain globotriaosylceramide synthase mRNA and the alternate Shiga toxin receptor globotetraosylceramide. Infect Immun 2010; 78:4488-99. [PMID: 20732996 DOI: 10.1128/iai.00620-10] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli O157:H7 and other Shiga toxin (Stx)-producing E. coli (STEC) bacteria are not enteroinvasive but can cause hemorrhagic colitis. In some STEC-infected individuals, a life-threatening sequela of infection called the hemolytic uremic syndrome may develop that can lead to kidney failure. This syndrome is linked to the production of Stx by the infecting organism. For Stx to reach the kidney, the toxin must first penetrate the colonic epithelial barrier. However, the Stx receptor, globotriaosylceramide (Gb3), has been thought to be absent from human intestinal epithelial cells. Thus, the mechanisms by which the toxin associates with and traverses through the intestine en route to the kidneys have been puzzling aspects of STEC pathogenesis. In this study, we initially determined that both types of Stx made by STEC, Stx1 and Stx2, do in fact bind to colonic epithelia in fresh tissue sections and to a colonic epithelial cell line (HCT-8). We also discovered that globotetraosylceramide (Gb4), a lower-affinity toxin receptor derived from Gb3, is readily detectable on the surfaces of human colonic tissue sections and HCT-8 cells. Furthermore, we found that Gb3 is present on a fraction of HCT-8 cells, where it presumably functions to bind and internalize Stx1 and Stx2. In addition, we established by quantitative real-time PCR (qRT-PCR) that both fresh colonic epithelial sections and HCT-8 cells express Gb3 synthase mRNA. Taken together, our data suggest that Gb3 may be present in small quantities in human colonic epithelia, where it may compete for Stx binding with the more abundantly expressed glycosphingolipid Gb4.
Collapse
|
23
|
Mohawk KL, Melton-Celsa AR, Robinson CM, O'Brien AD. Neutralizing antibodies to Shiga toxin type 2 (Stx2) reduce colonization of mice by Stx2-expressing Escherichia coli O157:H7. Vaccine 2010; 28:4777-85. [PMID: 20472033 DOI: 10.1016/j.vaccine.2010.04.099] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 04/22/2010] [Accepted: 04/28/2010] [Indexed: 11/17/2022]
Abstract
Previously, we showed that the Shiga toxin type 2 (Stx2)-expressing Escherichia coli O157:H7 strain 86-24 colonized mice better than did its isogenic stx(2) negative mutant. Here, we confirmed that finding by demonstrating that Stx2 given orally to mice increased the levels of the 86-24 stx(2) mutant shed in feces. Then we assessed the impact of Stx2-neutralizing antibodies, administered passively or generated by immunization with an Stx2 toxoid, on E. coli O157:H7 colonization of mice. We found that such antibodies reduced the E. coli O157:H7 burden in infected mice and, as anticipated, also protected them from weight loss and death.
Collapse
Affiliation(s)
- Krystle L Mohawk
- Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | | | | | | |
Collapse
|
24
|
Salyaev RK, Rekoslavskaya NI, Shchelkunov SN, Stolbikov AS, Hammond RV. Study of the mucosal immune response duration in mice after administration of a candidate edible vaccine based on transgenic tomato plants carrying the TBI-HBS gene. DOKL BIOCHEM BIOPHYS 2009; 428:232-4. [DOI: 10.1134/s1607672909050020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
25
|
Gu J, Liu Y, Yu S, Wang H, Wang Q, Yi Y, Zhu F, Yu XJ, Zou Q, Mao X. Enterohemorrhagic Escherichia coli trivalent recombinant vaccine containing EspA, intimin and Stx2 induces strong humoral immune response and confers protection in mice. Microbes Infect 2009; 11:835-41. [DOI: 10.1016/j.micinf.2009.04.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Revised: 04/22/2009] [Accepted: 04/23/2009] [Indexed: 11/27/2022]
|
26
|
Domon E, Takagi H, Hirose S, Sugita K, Kasahara S, Ebinuma H, Takaiwa F. 26-Week oral safety study in macaques for transgenic rice containing major human T-cell epitope peptides from Japanese cedar pollen allergens. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:5633-5638. [PMID: 19462978 DOI: 10.1021/jf900371u] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A study of repeated oral administration of transgenic rice containing a hybrid peptide of major human T-cell epitopes (7Crp) from Japanese cedar pollen allergens was carried out in cynomolgus macaques over 26 weeks. The monkeys were divided into three groups, each comprising three males and three females, administered a high dose of transgenic rice, a low dose of transgenic rice, or a high dose of the parental rice strain. The transgenic rice 7crp#10 and the parental nontransgenic control were polished, steamed, mashed, and prepared in water at 40% (w/v). Monkeys were orally administered a high or low dose of transgenic rice or the nontransgenic control by gavage every day. No adverse effects on general behavior or body weight of animals were observed during the study. Analysis of blood from monkeys administered for 26 weeks showed that, with few exceptions, there were no significant differences in hematological or biochemical values between them. Additionally, neither pathological symptoms nor histopathological abnormalities were observed. Thus, it was concluded that oral administration of transgenic rice containing T-cell epitopes from Japanese cedar pollen allergens has no adverse effects.
Collapse
MESH Headings
- Administration, Oral
- Animals
- Cryptomeria/immunology
- Desensitization, Immunologic
- Drug Evaluation, Preclinical
- Drug-Related Side Effects and Adverse Reactions
- Epitopes, T-Lymphocyte/administration & dosage
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Female
- Humans
- Immunotherapy
- Macaca
- Male
- Oryza/genetics
- Oryza/immunology
- Plant Proteins/administration & dosage
- Plant Proteins/genetics
- Plant Proteins/immunology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/immunology
- Pollen/immunology
- Rhinitis, Allergic, Seasonal/immunology
- Rhinitis, Allergic, Seasonal/therapy
Collapse
Affiliation(s)
- Eiji Domon
- Transgenic Crop Research and Development Center, National Institute for Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | | | | | | | | | | | | |
Collapse
|
27
|
Green BJ, Fujiki M, Mett V, Kaczmarczyk J, Shamloul M, Musiychuk K, Underkoffler S, Yusibov V, Mett V. Transient protein expression in three Pisum sativum (green pea) varieties. Biotechnol J 2009; 4:230-7. [PMID: 19156736 DOI: 10.1002/biot.200800256] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The expression of proteins in plants both transiently and via permanently transformed lines has been demonstrated by a number of groups. Transient plant expression systems, due to high expression levels and speed of production, show greater promise for the manufacturing of biopharmaceuticals when compared to permanent transformants. Expression vectors based on a tobacco mosaic virus (TMV) are the most commonly utilized and the primary plant used, Nicotiana benthamiana, has demonstrated the ability to express a wide range of proteins at levels amenable to purification. N. benthamiana has two limitations for its use; one is its relatively slow growth, and the other is its low biomass. To address these limitations we screened a number of legumes for transient protein expression. Using the alfalfa mosaic virus (AMV) and the cucumber mosaic virus (CMV) vectors, delivered via Agrobacterium, we were able to identify three Pisum sativum varieties that demonstrated protein expression transiently. Expression levels of 420 +/- 26.24 mg GFP/kgFW in the green pea variety speckled pea were achieved. We were also able to express three therapeutic proteins indicating promise for this system in the production of biopharmaceuticals.
Collapse
Affiliation(s)
- Brian J Green
- Fraunhofer USA Center for Molecular Biotechnology, Newark, DE 19711, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Orth D, Grif K, Zimmerhackl LB, Würzner R. Prevention and treatment of enterohemorrhagic Escherichia coli infections in humans. Expert Rev Anti Infect Ther 2008; 6:101-8. [PMID: 18251667 DOI: 10.1586/14787210.6.1.101] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Infections with enterohemorrhagic Escherichia coli (EHEC) result in various clinical symptoms and outcomes ranging from watery or bloody diarrhea to the life-threatening hemolytic-uremic syndrome (HUS). Shiga toxins (Stxs) are supposed to play a major role in the pathogenesis of EHEC infections; however, the role of other putative virulence factors is not fully elucidated. So far, there is only supportive therapy available for the treatment of both EHEC-associated diarrhea and HUS. Antibiotic therapy for the treatment of EHEC-associated diarrhea is discussed. In recent years other therapeutic strategies have been developed, including Gb3 receptor analogues, that bind Stx in the gut or in the circulation, passive immunization with Stx-neutralizing monoclonal antibodies, or active immunization with Stx1 And Stx2 toxoids as a preventive procedure. These approaches have been demonstrated to be effective in animal models but clinical trials are lacking.
Collapse
Affiliation(s)
- Dorothea Orth
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University and Austrian Reference Centre for Enterohaemorrhagic Escherichia coli, Schöpfstr. 41, A-6020 Innsbruck, Austria.
| | | | | | | |
Collapse
|
29
|
Tsuji T, Shimizu T, Sasaki K, Tsukamoto K, Arimitsu H, Ochi S, Shimizu T, Taniguchi K, Noda M, Neri P, Mori H. A nasal vaccine comprising B-subunit derivative of Shiga toxin 2 for cross-protection against Shiga toxin types 1 and 2. Vaccine 2008; 26:2092-9. [DOI: 10.1016/j.vaccine.2008.02.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 01/17/2008] [Accepted: 02/19/2008] [Indexed: 11/15/2022]
|
30
|
Neonatal sublingual vaccination with Salmonella proteins and adjuvant cholera toxin or CpG oligodeoxynucleotides induces mucosal and systemic immunity in mice. J Pediatr Gastroenterol Nutr 2008; 46:262-71. [PMID: 18376242 DOI: 10.1097/mpg.0b013e318156050d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Salmonella enteritidis is one of the most common enteric pathogens that cause acute gastroenteritis. A vaccine that can induce systemic and mucosal immune responses by a simple, noninvasive pathway and provide protection against this mucosal pathogen is needed. MATERIALS AND METHODS Newborn BALB/c mice were sublingually vaccinated daily for the first 3 days with sonicated Salmonella proteins (SSP) only, or SSP combined with adjuvant CpG or cholera toxin (CT). A booster vaccination was given 7 weeks after the last treatment. Serum and saliva antibody responses, cytokine profiles of spleen cells, survival rate, and intestinal morphology after live S enteritidis challenge were investigated. RESULTS Saliva-specific secretory IgA (SIgA) antibody responses were markedly enhanced by neonatal sublingual vaccination with SSP together with adjuvant CpG or CT. Whereas vaccination with SSP and CpG enhanced spleen cell interferon-gamma production and serum-specific IgG2a antibody responses, vaccination with SSP and CT increased spleen cell interleukin (IL)-4, IL-5, IL-6, and interferon-gamma production and serum-specific IgG1 and IgG2a antibody responses. Vaccination with SSP and CpG or CT protected against intestinal necrosis and was associated with a higher survival rate after oral challenge with live S enteritidis. The vaccinated mice with higher specific IgG and saliva-specific secretory IgA antibody levels had a better survival rate. CONCLUSIONS Neonatal sublingual vaccination with adjuvant CpG or CT can induce both mucosal and systemic immunity and may play a crucial role in protection against enteric pathogens.
Collapse
|
31
|
Joensuu JJ, Niklander-Teeri V, Brandle JE. Transgenic plants for animal health: plant-made vaccine antigens for animal infectious disease control. PHYTOCHEMISTRY REVIEWS : PROCEEDINGS OF THE PHYTOCHEMICAL SOCIETY OF EUROPE 2008; 7:553-577. [PMID: 32214922 PMCID: PMC7089046 DOI: 10.1007/s11101-008-9088-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Accepted: 02/05/2008] [Indexed: 05/19/2023]
Abstract
A variety of plant species have been genetically modified to accumulate vaccine antigens for human and animal health and the first vaccine candidates are approaching the market. The regulatory burden for animal vaccines is less than that for human use and this has attracted the attention of researchers and companies, and investment in plant-made vaccines for animal infectious disease control is increasing. The dosage cost of vaccines for animal infectious diseases must be kept to a minimum, especially for non-lethal diseases that diminish animal welfare and growth, so efficient and economic production, storage and delivery are critical for commercialization. It has become clear that transgenic plants are an economic and efficient alternative to fermentation for large-scale production of vaccine antigens. The oral delivery of plant-made vaccines is particularly attractive since the expensive purification step can be avoided further reducing the cost per dose. This review covers the current status of plant-produced vaccines for the prevention of disease in animals and focuses on barriers to the development of such products and methods to overcome them.
Collapse
Affiliation(s)
- J. J. Joensuu
- Department of Applied Biology, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON Canada N5V 4T3
| | - V. Niklander-Teeri
- Department of Applied Biology, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland
| | - J. E. Brandle
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON Canada N5V 4T3
| |
Collapse
|
32
|
Abstract
PURPOSE OF REVIEW Shiga toxin-producing Escherichia coli cause hemorrhagic colitis and hemolytic uremic syndrome. We will summarize the literature on incidence and outcomes of these infections, and then review the pathogenesis to explain the current recommendations against antibiotic use and to suggest alternative therapies. RECENT FINDINGS Shiga toxin-producing E. coli continue to be prevalent in the industrialized world because of dissemination in food products contaminated by ruminant feces. Declines in ground beef-related outbreaks have been matched by increased cases related to green vegetables. Fifteen percent of patients infected with E. coli O157:H7 progress to hemolytic uremic syndrome, but this figure may reach 50% if antibiotics are used. Mechanisms for bacteriophage induction causing Shiga toxin production, and for Shiga toxin dissemination to endothelium in gut, kidney and brain, may explain the negative effects of antibiotics and lead to rational therapies. Shiga toxin binders were not effective in clinical trials, but more avid binding agents may be. Current treatment recommendations are to maintain hydration to prevent thrombotic complications. Human vaccines are unlikely to be utilized. Cattle vaccines may prove the most significant approach to this disease. SUMMARY Improved understanding of Shiga toxin-producing Escherichia coli pathophysiology and progression to hemolytic uremic syndrome provides the basis for prevention, prophylactic and treatment strategies.
Collapse
|
33
|
Abstract
The need for minimally invasive delivery methods is urgent. As the number of registered vaccines increases, so does the number of injections. The use of sharps can be unsafe and needle immunisation is less suitable for mass immunisations during emergencies such as pandemics or bioterrorist attacks. The approach of combining vaccines has limitations due to high development costs, risk of pharmaceutical or immunological interference and economic risks. Advancements in the development of alternatives to injection with syringes and needles are discussed in this paper, and include: mucosal vaccination, injection without needles and vaccine delivery via the skin.
Collapse
Affiliation(s)
- Gideon Kersten
- Netherlands Vaccine Institute, Research and Development Department, PO Box 457, 3720 Al Bilthoven, The Netherlands.
| | | |
Collapse
|
34
|
Abstract
As early as 900 years ago, the Bedouins of the Negev desert were reported to kill a rabid dog, roast its liver and feed it to a dog-bitten person for three to five days according to the size and number of bites [1] . In sixteenth century China, physicians routinely prescribed pills made from the fleas collected from sick cows, which purportedly prevented smallpox. One may dismiss the wisdom of the Bedouins or Chinese but the Nobel laureate, Charles Richet, demonstrated in 1900 that feeding raw meat can cure tuberculous dogs - an approach he termed zomotherapy. Despite historical clues indicating the feasibility of oral vaccination, this particular field is notoriously infamous for the abundance of dead-end leads. Today, most commercial vaccines are delivered by injection, which has the principal limitation that recipients do not like needles. In the last few years, there has been a sharp increase in interest in needle-free vaccine delivery; new data emerges almost daily in the literature. So far, there are very few licensed oral vaccines, but many more vaccine candidates are in development. Vaccines delivered orally have the potential to take immunization to a fundamentally new level. In this review, the authors summarize the recent progress in the area of oral vaccines.
Collapse
MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Administration, Oral
- Animals
- Chemistry, Pharmaceutical
- Drug Carriers
- Drug Compounding
- Gastrointestinal Tract/immunology
- Humans
- Immune Tolerance
- Immunity, Mucosal
- Vaccination/methods
- Vaccination/trends
- Vaccines, Attenuated/administration & dosage
- Vaccines, Attenuated/chemistry
- Vaccines, Attenuated/immunology
- Vaccines, Edible/administration & dosage
- Vaccines, Edible/chemistry
- Vaccines, Edible/immunology
- Vaccines, Inactivated/administration & dosage
- Vaccines, Inactivated/chemistry
- Vaccines, Inactivated/immunology
Collapse
Affiliation(s)
- Dmytro S Silin
- Queen's University Belfast, Laboratory of Molecular Virology, Medical and Biology Center, School of Biomedical Sciences, 97 Lisburn Road, Belfast, BT9 7BL, UK
| | | | | | | |
Collapse
|
35
|
Vareille M, de Sablet T, Hindré T, Martin C, Gobert AP. Nitric oxide inhibits Shiga-toxin synthesis by enterohemorrhagic Escherichia coli. Proc Natl Acad Sci U S A 2007; 104:10199-204. [PMID: 17537918 PMCID: PMC1891265 DOI: 10.1073/pnas.0702589104] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Indexed: 11/18/2022] Open
Abstract
Shiga-toxin (Stx) is the cardinal virulence factor of enterohemorrhagic Escherichia coli (EHEC). The genes encoding Stx are carried by a lambdoid phage integrated in the bacterial genome and are fully expressed after a bacterial SOS response induced by DNA-damaging agents. Because nitric oxide (NO) is an essential mediator of the innate immune response of infected colonic mucosa, we aimed to determine its role in Stx production by EHEC. Here we demonstrate that chemical or cellular sources of NO inhibit spontaneous and mitomycin C-induced stx mRNA expression and Stx synthesis, without altering EHEC viability. The synthesis of stx phage is also reduced by NO. This inhibitory effect apparently occurs through the NO-mediated sensitization of EHEC because mutation of the NO sensor nitrite-sensitive repressor results in loss of NO inhibiting activity on stx expression. Thus our findings identify NO as an inhibitor of stx expressing-phage propagation and Stx release and thus as a potential protective factor limiting the development of hemolytic syndromes.
Collapse
Affiliation(s)
- Marjolaine Vareille
- Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Recherches de Theix, 63122 Saint-Genès-Champanelle, France
| | - Thibaut de Sablet
- Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Recherches de Theix, 63122 Saint-Genès-Champanelle, France
| | - Thomas Hindré
- Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Recherches de Theix, 63122 Saint-Genès-Champanelle, France
| | - Christine Martin
- Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Recherches de Theix, 63122 Saint-Genès-Champanelle, France
| | - Alain P. Gobert
- Institut National de la Recherche Agronomique (INRA), UR454 Unité de Microbiologie, Centre de Recherches de Theix, 63122 Saint-Genès-Champanelle, France
| |
Collapse
|
36
|
Hernández M, Cabrera-Ponce JL, Fragoso G, López-Casillas F, Guevara-García A, Rosas G, León-Ramírez C, Juárez P, Sánchez-García G, Cervantes J, Acero G, Toledo A, Cruz C, Bojalil R, Herrera-Estrella L, Sciutto E. A new highly effective anticysticercosis vaccine expressed in transgenic papaya. Vaccine 2007; 25:4252-60. [PMID: 17399859 DOI: 10.1016/j.vaccine.2007.02.080] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 02/20/2007] [Accepted: 02/23/2007] [Indexed: 10/23/2022]
Abstract
The use of transgenic plants as new antigen-delivery systems for subunit vaccines has been increasingly explored. We herein report progress toward a papaya-based vaccine against cysticercosis. Synthetic peptides (KETc1, KETc12, KETc7) were successfully expressed in 19 different transgenic papaya clones and found to be immunogenic. Complete protection against cysticercosis was induced with the soluble extract of the clones that expressed the higher levels of transcripts in up to 90% of the immunized mice. This study represents a key step towards the development of a more effective, sustainable and affordable oral subunit vaccine against human and pig cysticercosis.
Collapse
MESH Headings
- Animals
- Carica/genetics
- Cysticercosis/immunology
- Cysticercosis/prevention & control
- Cysticercus/growth & development
- Cysticercus/immunology
- Female
- Life Cycle Stages
- Mice
- Mice, Inbred BALB C
- Models, Animal
- Peritoneal Cavity/parasitology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/metabolism
- Vaccines, Subunit/genetics
- Vaccines, Subunit/immunology
- Vaccines, Subunit/isolation & purification
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/isolation & purification
Collapse
Affiliation(s)
- Marisela Hernández
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, D.F. 04510, México
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Abstract
Bovine manure is an important source of Escherichia coli O157 contamination of the environment and foods; therefore, effective interventions targeted at reducing the prevalence and magnitude of fecal E. coli O157 excretion by live cattle (preharvest) are desirable. Preharvest intervention methods can be grouped into 3 categories: 1) exposure reduction strategies, 2) exclusion strategies, and 3) direct antipathogen strategies. Exposure reduction involves environmental management targeted at reducing bovine exposure to E. coli O157 through biosecurity and environmental niche management such as feed and drinking water hygiene, reduced exposure to insects or wildlife, and improved cleanliness of the bedding or pen floor. In the category of exclusion, we group vaccination and dietary modifications such as selection of specific feed components; feeding of prebiotics, probiotics, or both; and supplementation with competitive exclusion cultures to limit proliferation of E. coli O157 in or on exposed animals. Direct antipathogen strategies include treatment with sodium chlorate, antibiotics, bacteriophages, in addition to washing of animals before slaughter. Presently, only 1 preharvest control for E. coli O157 in cattle has been effective and has gained widespread adoption-the feeding probiotic Lactobacillus acidophilus. More research into the effectiveness of parallel and simultaneous application of 1 or more preharvest control strategies, as well as the identification of new pre-harvest control methods, may provide practical means to substantially reduce the incidence of human E. coli O157-related illness by intervening at the farm level.
Collapse
Affiliation(s)
- J T LeJeune
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691, USA.
| | | |
Collapse
|
38
|
Moravec T, Schmidt MA, Herman EM, Woodford-Thomas T. Production of Escherichia coli heat labile toxin (LT) B subunit in soybean seed and analysis of its immunogenicity as an oral vaccine. Vaccine 2007; 25:1647-57. [PMID: 17188785 DOI: 10.1016/j.vaccine.2006.11.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 10/30/2006] [Accepted: 11/02/2006] [Indexed: 11/16/2022]
Abstract
The B subunit of the heat labile toxin of enterotoxigenic Escherichia coli (LTB) was used as a model immunogen for production in soybean seed. LTB expression was directed to the endoplasmic reticulum (ER) of seed storage parenchyma cells for sequestration in de novo synthesized inert protein accretions derived from the ER. Pentameric LTB accumulated to 2.4% of the total seed protein at maturity and was stable in desiccated seed. LTB-soybean extracts administered orally to mice induced both systemic IgG and IgA, and mucosal IgA antibody responses, and was particularly efficacious when used in a parenteral prime-oral gavage boost immunization strategy. Sera from immunized mice blocked ligand binding in vitro and immunized mice exhibited partial protection against LT challenge. Moreover, soybean-expressed LTB stimulated the antibody response against a co-administered antigen by 500-fold. These results demonstrate the utility of soybean as an efficient production platform for vaccines that can be used for oral delivery.
Collapse
Affiliation(s)
- Tomas Moravec
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, United States
| | | | | | | |
Collapse
|
39
|
Smith MJ, Carvalho HM, Melton-Celsa AR, O'Brien AD. The 13C4 monoclonal antibody that neutralizes Shiga toxin Type 1 (Stx1) recognizes three regions on the Stx1 B subunit and prevents Stx1 from binding to its eukaryotic receptor globotriaosylceramide. Infect Immun 2006; 74:6992-8. [PMID: 17030576 PMCID: PMC1698095 DOI: 10.1128/iai.01247-06] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Revised: 09/08/2006] [Accepted: 09/28/2006] [Indexed: 11/20/2022] Open
Abstract
The 13C4 monoclonal antibody (MAb) recognizes the B subunit of Stx1 (StxB1) and neutralizes the cytotoxic and lethal activities of Stx1. However, this MAb does not bind to the B polypeptide of Stx2, despite the 73% amino acid sequence similarity between StxB1 and StxB2. When we compared the amino acid sequences of StxB1 and StxB2, we noted three regions of dissimilarity (amino acids 1 to 6, 25 to 32, and 54 to 61) located near each other on the crystal structure of StxB1. To identify the 13C4 epitope, we generated seven Stx1/Stx2 B chimeric polypeptides that contained one, two, or three of the dissimilar StxB1 regions. The 13C4 MAb reacted strongly with StxB1 and the triple-chimeric B subunit but not with the other chimeras. Mice immunized with the triple-chimeric B subunit survived a lethal challenge with Stx1 but not Stx2, substantiating the identified regions as the 13C4 MAb epitope and suggesting that the incorporation of this epitope into StxB2 altered sites necessary for anti-Stx2-neutralizing Ab production. Next, single amino acid substitutions were made in StxB1 to mimic Stx1d, a variant not recognized by the 13C4 MAb. The 13C4 MAb reacted strongly to StxB1 with the T1A or G25A mutations but not with the N55T change. Finally, we found that the 13C4 MAb blocked the binding of Stx1 to its receptor, globotriaosyl ceramide. Taken together, these results indicate that the 13C4 MAb prevents the interaction of Stx1 with its receptor by binding three nonlinear regions of the molecule that span receptor recognition sites on StxB1, one of which includes the essential residue 55N.
Collapse
Affiliation(s)
- Michael J Smith
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Room B4052, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, USA
| | | | | | | |
Collapse
|
40
|
Bielaszewska M, Friedrich AW, Aldick T, Schürk-Bulgrin R, Karch H. Shiga Toxin Activatable by Intestinal Mucus in Escherichia coli Isolated from Humans: Predictor for a Severe Clinical Outcome. Clin Infect Dis 2006; 43:1160-7. [PMID: 17029135 DOI: 10.1086/508195] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Accepted: 07/05/2006] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Some Escherichia coli produce Shiga toxin (Stx) in which cytotoxicity is increased (activated) by intestinal mucus and elastase (Stx2d(activatable)). These strains are highly virulent in mice, but their association with human disease is poorly understood. We investigated the prevalence of Stx2d(activatable) among Stx-producing E. coli (STEC) isolated from humans and the association between production of this Stx and the clinical outcome of infection. METHODS A total of 922 STEC isolates obtained from patients with hemolytic uremic syndrome or bloody or nonbloody diarrhea or from asymptomatic carriers were tested for the gene encoding Stx2d(activatable) by PCR and PstI restriction analysis. The toxin activatibility by human and mouse intestinal mucus and by an elastase was determined by quantifying the cytotoxicity using the Vero cell assay. RESULTS The stx(2d-activatable) gene was identified in 60 (6.5%) of 922 STEC strains; in 31 of these strains, it was the sole stx gene. Thirty of these 31 strains produced Stx2d(activatable). All of them lacked the intimin-encoding eae gene. Among eae-negative STEC, which typically cause mild diarrhea or asymptomatic infection, production of Stx2d(activatable) was significantly associated with the ability to cause severe disease, including bloody diarrhea (P<.001), and with systemic complications, such as hemolytic uremic syndrome (P<.001). CONCLUSIONS Production of Stx2d(activatable) by the infecting STEC may predict a severe clinical outcome of the infection, with progression to hemolytic uremic syndrome. A prompt and comprehensive subtyping of stx genes in STEC isolates is necessary to alert the treating physician that a patient is at risk of developing hemolytic uremic syndrome, even though the infecting STEC lacks eae.
Collapse
Affiliation(s)
- Martina Bielaszewska
- National Consulting Laboratory on Hemolytic Uremic Syndrome, Institute for Hygiene, University of Munster, Munster, Germany.
| | | | | | | | | |
Collapse
|