1
|
Dixit S, Parashar J, Dhaked RK, Kumar A, Saxena N. Development and validation of streptavidin-biotin-based double antibody sandwich ELISA for ricin diagnosis. Int Immunopharmacol 2024; 132:111986. [PMID: 38574703 DOI: 10.1016/j.intimp.2024.111986] [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: 10/09/2023] [Revised: 03/01/2024] [Accepted: 03/28/2024] [Indexed: 04/06/2024]
Abstract
BACKGROUND Ricin is a potential biowarfare agent. It is a phytotoxin isolated from castor seeds. At present there is no antidote available for ricin poisoning, patients only get supportive treatment based on their symptoms. This highlights the importance of early detection to avoid severity of accidents and reduce the risk factor. Considering this, our study aimed to develop a highly sensitive and specific sandwich ELISA for the detection of ricin. METHODS Ricin was purified from castor seeds. Anti-ricin polyclonal and monoclonal antibodies were generated from rabbit antisera and hybridoma cell (1H6F1) supernatant using a protein A/G column. Antibody titer estimation was done using Indirect ELISA. A streptavidin-biotin-based sandwich ELISA was developed and the limit of detection (LOD), linear range, intra and inter-assay coefficient of variation (CV), and cross-reactivity with other similar toxins were determined. Interference of human plasma samples spiked with ricin was also checked. RESULTS The LOD of the ELISA was found to be 0.45 ng/ml, with a linear range of 0.90-62 ng/ml, intra and inter-assay CV ranged from 3.34 % to 5 % and 5.17 % to 10.80 % respectively. The assay was not cross-reactive with other similar ribosome-inactivating protein (RIP) toxins. Ricin was detected in spiked plasma samples. CONCLUSION The developed assay is highly sensitive and specific for detecting ricin and is not cross-reactive with other similar types of toxins. The assay can detect ricin in spiked plasma samples, so it has the potential to be used for the analysis of clinical samples after ricin poisoning.
Collapse
Affiliation(s)
- Shivani Dixit
- Division of Pharmacology & Toxicology, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior, India
| | - Jagrati Parashar
- Division of Pharmacology & Toxicology, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior, India
| | - Ram Kumar Dhaked
- Biotechnology Division, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior, India
| | - Abdhesh Kumar
- Animal Facility Division, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior, India
| | - Nandita Saxena
- Division of Pharmacology & Toxicology, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior, India.
| |
Collapse
|
2
|
Botelho FD, Franca TCC, LaPlante SR. The Search for Antidotes Against Ricin. Mini Rev Med Chem 2024; 24:1148-1161. [PMID: 38350844 DOI: 10.2174/0113895575270509231121060105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/30/2023] [Accepted: 10/18/2023] [Indexed: 02/15/2024]
Abstract
The castor plant (Ricinus communis) is primarily known for its seeds, which contain a unique fatty acid called ricinoleic acid with several industrial and commercial applications. Castor seeds also contain ricin, a toxin considered a chemical and biological warfare agent. Despite years of investigation, there is still no effective antidote or vaccine available. However, some progress has been made, and the development of an effective treatment may be on the horizon. To provide an updated overview of this issue, we have conducted a comprehensive review of the literature on the current state of research in the fight against ricin. This review is based on the reported research and aims to address the challenges faced by researchers, as well as highlight the most successful cases achieved thus far. Our goal is to encourage the scientific community to continue their efforts in this critical search.
Collapse
Affiliation(s)
- Fernanda Diniz Botelho
- Laboratory of Molecular Modeling Applied to the Chemical and Biological Defense (LMCBD), Military Institute of Engineering, Praça General Tibúrcio 80, 22290-270, Rio de Janeiro, RJ, Brazil
| | - Tanos Celmar Costa Franca
- Laboratory of Molecular Modeling Applied to the Chemical and Biological Defense (LMCBD), Military Institute of Engineering, Praça General Tibúrcio 80, 22290-270, Rio de Janeiro, RJ, Brazil
- Université de Québec, INRS - Centre Armand-Frappier Santé Biotechnologie, 531 boulevard des Prairies, Laval, Québec, H7V 1B7, Canada
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czech Republic
| | - Steven R LaPlante
- Université de Québec, INRS - Centre Armand-Frappier Santé Biotechnologie, 531 boulevard des Prairies, Laval, Québec, H7V 1B7, Canada
| |
Collapse
|
3
|
Targeting the Inside of Cells with Biologicals: Toxin Routes in a Therapeutic Context. BioDrugs 2023; 37:181-203. [PMID: 36729328 PMCID: PMC9893211 DOI: 10.1007/s40259-023-00580-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2023] [Indexed: 02/03/2023]
Abstract
Numerous toxins translocate to the cytosol in order to fulfil their function. This demonstrates the existence of routes for proteins from the extracellular space to the cytosol. Understanding these routes is relevant to multiple aspects related to therapeutic applications. These include the development of anti-toxin treatments, the potential use of toxins as shuttles for delivering macromolecular cargo to the cytosol or the use of drugs based on toxins. Compared with other strategies for delivery, such as chemicals as carriers for macromolecular delivery or physical methods like electroporation, toxin routes present paths into the cell that potentially cause less damage and can be specifically targeted. The efficiency of delivery via toxin routes is limited. However, low-delivery efficiencies can be entirely sufficient, if delivered cargoes possess an amplification effect or if very few molecules are sufficient for inducing the desired effects. This is known for example from RNA-based vaccines that have been developed during the coronavirus disease 2019 pandemic as well as for other approved RNA-based drugs, which elicited the desired effect despite their typically low delivery efficiencies. The different mechanisms by which toxins enter cells may have implications for their technological utility. We review the mechanistic principles of the translocation pathway of toxins from the extracellular space to the cytosol, the delivery efficiencies, and therapeutic strategies or applications that exploit toxin routes for intracellular delivery.
Collapse
|
4
|
Rasetti-Escargueil C, Avril A. Medical Countermeasures against Ricin Intoxication. Toxins (Basel) 2023; 15:toxins15020100. [PMID: 36828415 PMCID: PMC9966136 DOI: 10.3390/toxins15020100] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 12/14/2022] [Accepted: 01/16/2023] [Indexed: 01/22/2023] Open
Abstract
Ricin toxin is a disulfide-linked glycoprotein (AB toxin) comprising one enzymatic A chain (RTA) and one cell-binding B chain (RTB) contained in the castor bean, a Ricinus species. Ricin inhibits peptide chain elongation via disruption of the binding between elongation factors and ribosomes, resulting in apoptosis, inflammation, oxidative stress, and DNA damage, in addition to the classically known rRNA damage. Ricin has been used in traditional medicine throughout the world since prehistoric times. Because ricin toxin is highly toxic and can be readily extracted from beans, it could be used as a bioweapon (CDC B-list). Due to its extreme lethality and potential use as a biological weapon, ricin toxin remains a global public health concern requiring specific countermeasures. Currently, no specific treatment for ricin intoxication is available. This review focuses on the drugs under development. In particular, some examples are reviewed to demonstrate the proof of concept of antibody-based therapy. Chemical inhibitors, small proteins, and vaccines can serve as alternatives to antibodies or may be used in combination with antibodies.
Collapse
Affiliation(s)
- Christine Rasetti-Escargueil
- Unité des Bactéries Anaérobies et Toxines, Institut Pasteur, 25 Avenue du Docteur Roux, 75015 Paris, France
- Correspondence:
| | - Arnaud Avril
- Unité Immunopathologies, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, 91220 Brétigny-sur-Orge, France
| |
Collapse
|
5
|
Ricin toxin and its neutralizing antibodies: A review. Toxicon 2022; 214:47-53. [PMID: 35595086 DOI: 10.1016/j.toxicon.2022.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/22/2022]
Abstract
Ricin toxin (RT) belongs to the ribosome-inactivating protein (RIP) family of toxins and is considered to be a moderate threat by the US Center of Disease Control and Prevention (CDC). RT poses a great potential threat to the public, but there has been a lack of effective treatment options so far. Over the past few decades, researches on the prevention and treatment of RT poisoning have been investigated, among which neutralizing antibodies targeting RT specifically have always been a research hotspot. In this review, we have summarized the mechanism of action of RT, the research results and the design strategies of RT neutralizing antibodies, and discussed the key issues in the development of RT neutralizing antibody researches.
Collapse
|
6
|
Luo L, Yang J, Li Z, Xu H, Guo L, Wang L, Wang Y, Luo L, Wang J, Zhang P, Yang R, Kang W, Xie J. Label-free differentiation and quantification of ricin, abrin from their agglutinin biotoxins by surface plasmon resonance. Talanta 2022; 238:122860. [PMID: 34857316 DOI: 10.1016/j.talanta.2021.122860] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/31/2021] [Accepted: 09/05/2021] [Indexed: 01/17/2023]
Abstract
Here we describe an affinity molecule-directed surface plasmon resonance (SPR) immunosensor for a label-free, differentiation and quantification of ricin and abrin from their structural highly like agglutinin biotoxins. By an introduction of protein G as the affinity capturing molecule, we fulfilled a complete strategy contains (i) screening monoclonal antibodies to be paired in a sandwiched format, (ii) differentiate quantification from the agglutinin, (iii) ascertain of active from inactive biotoxin, and (iv) structural identification of captured biotoxins on a single chip. By the aid of an enrichment step from immunomagnetic beads, we could accurately measure ricin or abrin with a concentration lowered to 0.6 ng/mL (10 pM) in different complex matrices such as stevia, protein powder, and human plasma, with linear ranges of two or three orders of magnitude, and satisfied recovery. We then differentially quantified the mixed crude extracts from castor beans and jequirity peas, and real samples from the fourth OPCW biotoxin exercise to prove the practical availability. We further provided a SPR-mass spectrometric evidence directly obtained from Protein G affinity chip via a noncovalent molecule surface for the first time for definitely structural identification for crude extracts.
Collapse
Affiliation(s)
- Li Luo
- School of Public Health, Hebei Medical University, Shijiazhuang, 050017, China; State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Jiewei Yang
- State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Zhi Li
- State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Hua Xu
- State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China
| | - Lei Guo
- State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China.
| | - Lili Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, and Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Yuxia Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, and Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Longlong Luo
- State Key Laboratory of Toxicology and Medical Countermeasures, and Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Jing Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, and Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China
| | - Pingping Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Ruifu Yang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Weijun Kang
- School of Public Health, Hebei Medical University, Shijiazhuang, 050017, China.
| | - Jianwei Xie
- State Key Laboratory of Toxicology and Medical Countermeasures, and Laboratory of Toxicant Analysis, Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing, 100850, China
| |
Collapse
|
7
|
Saxena N, Phatak P, Chauhan V. Differential toxicity of abrin in human cell lines of different organ origin. Toxicol In Vitro 2021; 78:105250. [PMID: 34601064 DOI: 10.1016/j.tiv.2021.105250] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 08/25/2021] [Accepted: 09/27/2021] [Indexed: 11/27/2022]
Abstract
Abrus precatorius is a highly toxic seed containing the poison abrin. Similar in properties to ricin, this toxin binds to ribosomes causing cessation of protein synthesis and cell death. With an estimated human lethal dose of 0.1-1 μg/kg, it has been the cause of fatalities due to accidental and intentional ingestion. In present study, we profiled seven human cell lines of different organ origin, for their sensitivity against abrin toxicity. These cell lines are, A549, COLO 205, HEK 293, HeLa, Hep G2, Jurkat, SH-SY5Y and derived from lung, intestine, kidney, cervix, liver, immune and nervous system respectively. MTT, NR, CVDE and LDH assays have been used to determine their response against abrin toxin. Among these cell lines A549 was the most sensitive cell line while Hep G2 was found least sensitive cell lines. Hep G2 cells are shown to have mitochondrial resistance and delayed generation of oxidative stress compared to A549 cells. Remarkable variation in sensitivity against abrin toxicity prompted the evaluation of Bcl2, Bax and downstream caspases in both cells. Difference in Bcl2 level has been shown to play important role in variable sensitivity. Findings of present study are helpful for selection of suitable cellular model for toxicity assessment and antidote screening.
Collapse
Affiliation(s)
- Nandita Saxena
- Division of Pharmacology & Toxicology, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior 474002, India.
| | - Pooja Phatak
- Division of Pharmacology & Toxicology, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior 474002, India
| | - Vinita Chauhan
- Biotechnology Division, Defence Research Development & Establishment, Defence Research Development Organization, Gwalior 474002, India
| |
Collapse
|
8
|
Rudolph MJ, Poon AY, Kavaliauskiene S, Myrann AG, Reynolds-Peterson C, Davis SA, Sandvig K, Vance DJ, Mantis NJ. Structural Analysis of Toxin-Neutralizing, Single-Domain Antibodies that Bridge Ricin's A-B Subunit Interface. J Mol Biol 2021; 433:167086. [PMID: 34089718 DOI: 10.1016/j.jmb.2021.167086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/18/2021] [Accepted: 05/27/2021] [Indexed: 01/20/2023]
Abstract
Ricin toxin kills mammalian cells with notorious efficiency. The toxin's B subunit (RTB) is a Gal/GalNAc-specific lectin that attaches to cell surfaces and promotes retrograde transport of ricin's A subunit (RTA) to the trans Golgi network (TGN) and endoplasmic reticulum (ER). RTA is liberated from RTB in the ER and translocated into the cell cytoplasm, where it functions as a ribosome-inactivating protein. While antibodies against ricin's individual subunits have been reported, we now describe seven alpaca-derived, single-domain antibodies (VHHs) that span the RTA-RTB interface, including four Tier 1 VHHs with IC50 values <1 nM. Crystal structures of each VHH bound to native ricin holotoxin revealed three different binding modes, based on contact with RTA's F-G loop (mode 1), RTB's subdomain 2γ (mode 2) or both (mode 3). VHHs in modes 2 and 3 were highly effective at blocking ricin attachment to HeLa cells and immobilized asialofetuin, due to framework residues (FR3) that occupied the 2γ Gal/GalNAc-binding pocket and mimic ligand. The four Tier 1 VHHs also interfered with intracellular functions of RTB, as they neutralized ricin in a post-attachment cytotoxicity assay (e.g., the toxin was bound to cell surfaces before antibody addition) and reduced the efficiency of toxin transport to the TGN. We conclude that the RTA-RTB interface is a target of potent toxin-neutralizing antibodies that interfere with both extracellular and intracellular events in ricin's cytotoxic pathway.
Collapse
Affiliation(s)
| | - Amanda Y Poon
- Department of Biomedical Sciences, University at Albany, Albany, NY, USA; Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
| | - Anne Grethe Myrann
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
| | - Claire Reynolds-Peterson
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Simon A Davis
- New York Structural Biology Center, New York, NY, USA
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway
| | - David J Vance
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Nicholas J Mantis
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA.
| |
Collapse
|
9
|
Orsini Delgado ML, Avril A, Prigent J, Dano J, Rouaix A, Worbs S, Dorner BG, Rougeaux C, Becher F, Fenaille F, Livet S, Volland H, Tournier JN, Simon S. Ricin Antibodies' Neutralizing Capacity against Different Ricin Isoforms and Cultivars. Toxins (Basel) 2021; 13:100. [PMID: 33573016 PMCID: PMC7911099 DOI: 10.3390/toxins13020100] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 12/11/2022] Open
Abstract
Ricin, a highly toxic protein from Ricinus communis, is considered a potential biowarfare agent. Despite the many data available, no specific treatment has yet been approved. Due to their ability to provide immediate protection, antibodies (Abs) are an approach of choice. However, their high specificity might compromise their capacity to protect against the different ricin isoforms (D and E) found in the different cultivars. In previous work, we have shown the neutralizing potential of different Abs (43RCA-G1 (anti ricin A-chain) and RB34 and RB37 (anti ricin B-chain)) against ricin D. In this study, we evaluated their protective capacity against both ricin isoforms. We show that: (i) RB34 and RB37 recognize exclusively ricin D, whereas 43RCA-G1 recognizes both isoforms, (ii) their neutralizing capacity in vitro varies depending on the cultivar, and (iii) there is a synergistic effect when combining RB34 and 43RCA-G1. This effect is also demonstrated in vivo in a mouse model of intranasal intoxication with ricin D/E (1:1), where approximately 60% and 40% of mice treated 0 and 6 h after intoxication, respectively, are protected. Our results highlight the importance of evaluating the effectiveness of the Abs against different ricin isoforms to identify the treatment with the broadest spectrum neutralizing effect.
Collapse
Affiliation(s)
- Maria Lucia Orsini Delgado
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Arnaud Avril
- Microbiology and Infectious Diseases Department, Anti-Infectious Biotherapies and Immunity Unit, Army Biomedical Research Institute, 91220 Brétigny-sur-Orge, France; (A.A.); (C.R.); (J.-N.T.)
| | - Julie Prigent
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Julie Dano
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Audrey Rouaix
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Sylvia Worbs
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute (RKI), 13353 Berlin, Germany; (S.W.); (B.G.D.)
| | - Brigitte G. Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute (RKI), 13353 Berlin, Germany; (S.W.); (B.G.D.)
| | - Clémence Rougeaux
- Microbiology and Infectious Diseases Department, Anti-Infectious Biotherapies and Immunity Unit, Army Biomedical Research Institute, 91220 Brétigny-sur-Orge, France; (A.A.); (C.R.); (J.-N.T.)
| | - François Becher
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - François Fenaille
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Sandrine Livet
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Hervé Volland
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| | - Jean-Nicolas Tournier
- Microbiology and Infectious Diseases Department, Anti-Infectious Biotherapies and Immunity Unit, Army Biomedical Research Institute, 91220 Brétigny-sur-Orge, France; (A.A.); (C.R.); (J.-N.T.)
| | - Stéphanie Simon
- Paris-Saclay University, CEA, INRAE, Medicines and Healthcare Technologies Department (DMTS), SPI, 91191 Gif-sur-Yvette, France; (J.P.); (J.D.); (A.R.); (F.B.); (F.F.); (S.L.); (H.V.)
| |
Collapse
|
10
|
Vance DJ, Poon AY, Mantis NJ. Sites of vulnerability on ricin B chain revealed through epitope mapping of toxin-neutralizing monoclonal antibodies. PLoS One 2020; 15:e0236538. [PMID: 33166282 PMCID: PMC7652295 DOI: 10.1371/journal.pone.0236538] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/26/2020] [Indexed: 12/16/2022] Open
Abstract
Ricin toxin's B subunit (RTB) is a multifunctional galactose (Gal)-/N-acetylgalactosamine (GalNac)-specific lectin that promotes uptake and intracellular trafficking of ricin's ribosome-inactivating subunit (RTA) into mammalian cells. Structurally, RTB consists of two globular domains (RTB-D1, RTB-D2), each divided into three homologous sub-domains (α, β, γ). The two carbohydrate recognition domains (CRDs) are situated on opposite sides of RTB (sub-domains 1α and 2γ) and function non-cooperatively. Previous studies have revealed two distinct classes of toxin-neutralizing, anti-RTB monoclonal antibodies (mAbs). Type I mAbs, exemplified by SylH3, inhibit (~90%) toxin attachment to cell surfaces, while type II mAbs, epitomized by 24B11, interfere with intracellular toxin transport between the plasma membrane and the trans-Golgi network (TGN). Localizing the epitopes recognized by these two classes of mAbs has proven difficult, in part because of RTB's duplicative structure. To circumvent this problem, RTB-D1 and RTB-D2 were expressed as pIII fusion proteins on the surface of filamentous phage M13 and subsequently used as "bait" in mAb capture assays. We found that SylH3 captured RTB-D1 (but not RTB-D2) in a dose-dependent manner, while 24B11 captured RTB-D2 (but not RTB-D1) in a dose-dependent manner. We confirmed these domain assignments by competition studies with an additional 8 RTB-specific mAbs along with a dozen a single chain antibodies (VHHs). Collectively, these results demonstrate that type I and type II mAbs segregate on the basis of domain specificity and suggest that RTB's two domains may contribute to distinct steps in the intoxication pathway.
Collapse
Affiliation(s)
- David J. Vance
- Division of Infectious Disease, New York State Department of Health,Wadsworth Center, Albany, NY, United States of America
| | - Amanda Y. Poon
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, NY, United States of America
| | - Nicholas J. Mantis
- Division of Infectious Disease, New York State Department of Health,Wadsworth Center, Albany, NY, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, NY, United States of America
| |
Collapse
|
11
|
Rong Y, Torres-Velez FJ, Ehrbar D, Doering J, Song R, Mantis NJ. An intranasally administered monoclonal antibody cocktail abrogates ricin toxin-induced pulmonary tissue damage and inflammation. Hum Vaccin Immunother 2019; 16:793-807. [PMID: 31589555 DOI: 10.1080/21645515.2019.1664243] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Ricin toxin, a plant-derived, mannosylated glycoprotein, elicits an incapacitating and potentially lethal inflammatory response in the airways following inhalation. Uptake of ricin by alveolar macrophages (AM) and other pulmonary cell types occurs via two parallel pathways: one mediated by ricin's B subunit (RTB), a galactose-specific lectin, and one mediated by the mannose receptor (MR;CD206). Ricin's A subunit (RTA) is a ribosome-inactivating protein that triggers apoptosis in mammalian cells. It was recently reported that a single monoclonal antibody (MAb), PB10, directed against an immunodominant epitope on RTA and administered intravenously, was able to rescue Rhesus macaques from lethal aerosol dose of ricin. In this study, we now demonstrate in mice that the effectiveness PB10 is significantly improved when combined with a second MAb, SylH3, against RTB. Mice treated with PB10 alone survived lethal-dose intranasal ricin challenge, but experienced significant weight loss, moderate pulmonary inflammation (e.g., elevated IL-1 and IL-6 levels, PMN influx), and apoptosis of lung macrophages. In contrast, mice treated with the PB10/SylH3 cocktail were essentially impervious to pulmonary ricin toxin exposure, as evidenced by no weight loss, no change in local IL-1 and IL-6 levels, retention of lung macrophages, and a significant dampening of PMN recruitment into the bronchoalveolar lavage (BAL) fluids. The PB10/SylH3 cocktail only marginally reduced ricin binding to target cells in the BAL, suggesting that the antibody mixture neutralizes ricin by interfering with one or more steps in the RTB- and MR-dependent uptake pathways.
Collapse
Affiliation(s)
- Yinghui Rong
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| | - Fernando J Torres-Velez
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| | - Dylan Ehrbar
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| | - Jennifer Doering
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| | - Renjie Song
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| | - Nicholas J Mantis
- New York State Department of Health, Division of Infectious Disease, Wadsworth Center, Albany, NY, USA
| |
Collapse
|
12
|
Franke H, Scholl R, Aigner A. Ricin and Ricinus communis in pharmacology and toxicology-from ancient use and "Papyrus Ebers" to modern perspectives and "poisonous plant of the year 2018". Naunyn Schmiedebergs Arch Pharmacol 2019; 392:1181-1208. [PMID: 31359089 DOI: 10.1007/s00210-019-01691-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/04/2019] [Indexed: 12/19/2022]
Abstract
While probably originating from Africa, the plant Ricinus communis is found nowadays around the world, grown for industrial use as a source of castor oil production, wildly sprouting in many regions, or used as ornamental plant. As regards its pharmacological utility, a variety of medical purposes of selected parts of the plant, e.g., as a laxative, an anti-infective, or an anti-inflammatory drug, have been described already in the sixteenth century BC in the famous Papyrus Ebers (treasured in the Library of the University of Leipzig). Quite in contrast, on the toxicological side, the native plant has become the "poisonous plant 2018" in Germany. As of today, a number of isolated components of the plant/seeds have been characterized, including, e.g., castor oil, ricin, Ricinus communis agglutinin, ricinin, nudiflorin, and several allergenic compounds. This review mainly focuses on the most toxic protein, ricin D, classified as a type 2 ribosome-inactivating protein (RIP2). Ricin is one of the most potent and lethal substances known. It has been considered as an important bioweapon (categorized as a Category B agent (second-highest priority)) and an attractive agent for bioterroristic activities. On the other hand, ricin presents great potential, e.g., as an anti-cancer agent or in cell-based research, and is even explored in the context of nanoparticle formulations in tumor therapy. This review provides a comprehensive overview of the pharmacology and toxicology-related body of knowledge on ricin. Toxicokinetic/toxicodynamic aspects of ricin poisoning and possibilities for analytical detection and therapeutic use are summarized as well.
Collapse
Affiliation(s)
- Heike Franke
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Medical Faculty, University of Leipzig, Haertelstrasse 16-18, 04107, Leipzig, Germany.
| | - Reinhold Scholl
- Department of History, University of Leipzig, Leipzig, Germany
| | - Achim Aigner
- Rudolf-Boehm-Institute of Pharmacology and Toxicology, Clinical Pharmacology, Medical Faculty, University of Leipzig, Leipzig, Germany
| |
Collapse
|
13
|
Hobbs RJ, Thomas CA, Halliwell J, Gwenin CD. Rapid Detection of Botulinum Neurotoxins-A Review. Toxins (Basel) 2019; 11:E418. [PMID: 31319550 PMCID: PMC6669533 DOI: 10.3390/toxins11070418] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/15/2019] [Accepted: 07/15/2019] [Indexed: 12/13/2022] Open
Abstract
A toxin is a poisonous substance produced within living cells or organisms. One of the most potent groups of toxins currently known are the Botulinum Neurotoxins (BoNTs). These are so deadly that as little as 62 ng could kill an average human; to put this into context that is approximately 200,000 × less than the weight of a grain of sand. The extreme toxicity of BoNTs leads to the need for methods of determining their concentration at very low levels of sensitivity. Currently the mouse bioassay is the most widely used detection method monitoring the activity of the toxin; however, this assay is not only lengthy, it also has both cost and ethical issues due to the use of live animals. This review focuses on detection methods both existing and emerging that remove the need for the use of animals and will look at three areas; speed of detection, sensitivity of detection and finally cost. The assays will have wide reaching interest, ranging from the pharmaceutical/clinical industry for production quality management or as a point of care sensor in suspected cases of botulism, the food industry as a quality control measure, to the military, detecting BoNT that has been potentially used as a bio warfare agent.
Collapse
Affiliation(s)
- Robert J Hobbs
- Applied Research in Chemistry and Health (ARCH) Research Group, School of Natural Sciences, Bangor University, Bangor, Gwynedd, Wales LL57 2UW, UK
| | - Carol A Thomas
- Applied Research in Chemistry and Health (ARCH) Research Group, School of Natural Sciences, Bangor University, Bangor, Gwynedd, Wales LL57 2UW, UK
| | - Jennifer Halliwell
- Applied Research in Chemistry and Health (ARCH) Research Group, School of Natural Sciences, Bangor University, Bangor, Gwynedd, Wales LL57 2UW, UK
| | - Christopher D Gwenin
- Applied Research in Chemistry and Health (ARCH) Research Group, School of Natural Sciences, Bangor University, Bangor, Gwynedd, Wales LL57 2UW, UK.
| |
Collapse
|
14
|
Whole-Cell Multiparameter Assay for Ricin and Abrin Activity-Based Digital Holographic Microscopy. Toxins (Basel) 2019; 11:toxins11030174. [PMID: 30909438 PMCID: PMC6468687 DOI: 10.3390/toxins11030174] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 03/11/2019] [Accepted: 03/15/2019] [Indexed: 01/25/2023] Open
Abstract
Ricin and abrin are ribosome-inactivating proteins leading to inhibition of protein synthesis and cell death. These toxins are considered some of the most potent and lethal toxins against which there is no available antidote. Digital holographic microscopy (DHM) is a time-lapse, label-free, and noninvasive imaging technique that can provide phase information on morphological features of cells. In this study, we employed DHM to evaluate the morphological changes of cell lines during ricin and abrin intoxication. We showed that the effect of these toxins is characterized by a decrease in cell confluence and changes in morphological parameters such as cell area, perimeter, irregularity, and roughness. In addition, changes in optical parameters such as phase-shift, optical thickness, and effective-calculated volume were observed. These effects were completely inhibited by specific neutralizing antibodies. An enhanced intoxication effect was observed for preadherent compared to adherent cells, as was detected in early morphology changes and confirmed by annexin V/propidium iodide (PI) apoptosis assay. Detection of the dynamic changes in cell morphology at initial stages of cell intoxication by DHM emphasizes the highly sensitive and rapid nature of this method, allowing the early detection of active toxins.
Collapse
|
15
|
Janik E, Ceremuga M, Saluk-Bijak J, Bijak M. Biological Toxins as the Potential Tools for Bioterrorism. Int J Mol Sci 2019; 20:E1181. [PMID: 30857127 PMCID: PMC6429496 DOI: 10.3390/ijms20051181] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 02/24/2019] [Accepted: 03/03/2019] [Indexed: 12/16/2022] Open
Abstract
Biological toxins are a heterogeneous group produced by living organisms. One dictionary defines them as "Chemicals produced by living organisms that have toxic properties for another organism". Toxins are very attractive to terrorists for use in acts of bioterrorism. The first reason is that many biological toxins can be obtained very easily. Simple bacterial culturing systems and extraction equipment dedicated to plant toxins are cheap and easily available, and can even be constructed at home. Many toxins affect the nervous systems of mammals by interfering with the transmission of nerve impulses, which gives them their high potential in bioterrorist attacks. Others are responsible for blockage of main cellular metabolism, causing cellular death. Moreover, most toxins act very quickly and are lethal in low doses (LD50 < 25 mg/kg), which are very often lower than chemical warfare agents. For these reasons we decided to prepare this review paper which main aim is to present the high potential of biological toxins as factors of bioterrorism describing the general characteristics, mechanisms of action and treatment of most potent biological toxins. In this paper we focused on six most danger toxins: botulinum toxin, staphylococcal enterotoxins, Clostridium perfringens toxins, ricin, abrin and T-2 toxin. We hope that this paper will help in understanding the problem of availability and potential of biological toxins.
Collapse
Affiliation(s)
- Edyta Janik
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
| | - Michal Ceremuga
- CBRN Reconnaissance and Decontamination Department, Military Institute of Chemistry and Radiometry, Antoniego Chrusciela "Montera" 105, 00-910 Warsaw, Poland.
| | - Joanna Saluk-Bijak
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
| | - Michal Bijak
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
| |
Collapse
|
16
|
Bansia H, Bagaria S, Karande AA, Ramakumar S. Structural basis for neutralization of cytotoxic abrin by monoclonal antibody D6F10. FEBS J 2019; 286:1003-1029. [DOI: 10.1111/febs.14716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/02/2018] [Accepted: 11/30/2018] [Indexed: 11/26/2022]
Affiliation(s)
- Harsh Bansia
- Department of Physics Indian Institute of Science Bengaluru India
| | - Shradha Bagaria
- Department of Biochemistry Indian Institute of Science Bengaluru India
| | | | | |
Collapse
|
17
|
An imaging flow cytometry method to assess ricin trafficking in A549 human lung epithelial cells. Methods 2018; 134-135:41-49. [DOI: 10.1016/j.ymeth.2017.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 10/12/2017] [Accepted: 10/30/2017] [Indexed: 11/18/2022] Open
|
18
|
Whitfield SJC, Griffiths GD, Jenner DC, Gwyther RJ, Stahl FM, Cork LJ, Holley JL, Green AC, Clark GC. Production, Characterisation and Testing of an Ovine Antitoxin against Ricin; Efficacy, Potency and Mechanisms of Action. Toxins (Basel) 2017; 9:E329. [PMID: 29057798 PMCID: PMC5666376 DOI: 10.3390/toxins9100329] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 10/10/2017] [Accepted: 10/13/2017] [Indexed: 12/18/2022] Open
Abstract
Ricin is a type II ribosome-inactivating toxin that catalytically inactivates ribosomes ultimately leading to cell death. The toxicity of ricin along with the prevalence of castor beans (its natural source) has led to its increased notoriety and incidences of nefarious use. Despite these concerns, there are no licensed therapies available for treating ricin intoxication. Here, we describe the development of a F(ab')₂ polyclonal ovine antitoxin against ricin and demonstrate the efficacy of a single, post-exposure, administration in an in vivo murine model of intoxication against aerosolised ricin. We found that a single dose of antitoxin afforded a wide window of opportunity for effective treatment with 100% protection observed in mice challenged with aerosolised ricin when given 24 h after exposure to the toxin and 75% protection when given at 30 h. Treated mice had reduced weight loss and clinical signs of intoxication compared to the untreated control group. Finally, using imaging flow cytometry, it was found that both cellular uptake and intracellular trafficking of ricin toxin to the Golgi apparatus was reduced in the presence of the antitoxin suggesting both actions can contribute to the therapeutic mechanism of a polyclonal antitoxin. Collectively, the research highlights the significant potential of the ovine F(ab')₂ antitoxin as a treatment for ricin intoxication.
Collapse
Affiliation(s)
- Sarah J C Whitfield
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Gareth D Griffiths
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Dominic C Jenner
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Robert J Gwyther
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Fiona M Stahl
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Lucy J Cork
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Jane L Holley
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK
| | - A Christopher Green
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| | - Graeme C Clark
- Chemical, Biological and Radiological Division, Dstl, Porton Down, Salisbury SP4 0JQ, UK.
| |
Collapse
|
19
|
Gal Y, Mazor O, Falach R, Sapoznikov A, Kronman C, Sabo T. Treatments for Pulmonary Ricin Intoxication: Current Aspects and Future Prospects. Toxins (Basel) 2017; 9:E311. [PMID: 28972558 PMCID: PMC5666358 DOI: 10.3390/toxins9100311] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 09/26/2017] [Accepted: 09/29/2017] [Indexed: 12/13/2022] Open
Abstract
Ricin, a plant-derived toxin originating from the seeds of Ricinus communis (castor beans), is one of the most lethal toxins known, particularly if inhaled. Ricin is considered a potential biological threat agent due to its high availability and ease of production. The clinical manifestation of pulmonary ricin intoxication in animal models is closely related to acute respiratory distress syndrome (ARDS), which involves pulmonary proinflammatory cytokine upregulation, massive neutrophil infiltration and severe edema. Currently, the only post-exposure measure that is effective against pulmonary ricinosis at clinically relevant time-points following intoxication in pre-clinical studies is passive immunization with anti-ricin neutralizing antibodies. The efficacy of this antitoxin treatment depends on antibody affinity and the time of treatment initiation within a limited therapeutic time window. Small-molecule compounds that interfere directly with the toxin or inhibit its intracellular trafficking may also be beneficial against ricinosis. Another approach relies on the co-administration of antitoxin antibodies with immunomodulatory drugs, thereby neutralizing the toxin while attenuating lung injury. Immunomodulators and other pharmacological-based treatment options should be tailored according to the particular pathogenesis pathways of pulmonary ricinosis. This review focuses on the current treatment options for pulmonary ricin intoxication using anti-ricin antibodies, disease-modifying countermeasures, anti-ricin small molecules and their various combinations.
Collapse
Affiliation(s)
- Yoav Gal
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Ohad Mazor
- Department of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Reut Falach
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Anita Sapoznikov
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Chanoch Kronman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Tamar Sabo
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| |
Collapse
|
20
|
Rong Y, Van Slyke G, Vance DJ, Westfall J, Ehrbar D, Mantis NJ. Spatial location of neutralizing and non-neutralizing B cell epitopes on domain 1 of ricin toxin's binding subunit. PLoS One 2017; 12:e0180999. [PMID: 28700745 PMCID: PMC5507285 DOI: 10.1371/journal.pone.0180999] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 06/23/2017] [Indexed: 12/14/2022] Open
Abstract
Ricin toxin’s binding subunit (RTB) is a galactose-/N-acetylgalactosamine (Gal/GalNac)-specific lectin that mediates uptake and intracellular trafficking of ricin within mammalian cells. Structurally, RTB consists of two globular domains, each divided into three homologous sub-domains (α, β, γ). In this report, we describe five new murine IgG monoclonal antibodies (mAbs) against RTB: MH3, 8A1, 8B3, LF1, and LC5. The mAbs have similar binding affinities (KD) for ricin holotoxin, but displayed a wide range of in vitro toxin-neutralizing activities. Competition ELISAs indicate that the two most potent toxin-neutralizing mAbs (MH3, 8A1), as well as one of the moderate toxin-neutralizing mAbs (LF1), recognize distinct epitopes near the low affinity Gal recognition domain in RTB subdomain 1α. Evaluated in a mouse model of systemic ricin challenge, all five mAbs afforded some benefit against intoxication, but only MH3 was protective. However, neither MH3 nor 24B11, another well-characterized mAb against RTB subdomain 1α, could passively protect mice against a mucosal (intranasal) ricin challenge. This is in contrast to SylH3, a previously characterized mAb directed against an epitope near RTB’s high affinity Gal/GalNac recognition element in sub-domain 2γ, which protected animals against systemic and mucosal ricin exposure. SylH3 was significantly more effective than MH3 and 24B11 at blocking ricin attachment to host cell receptors, suggesting that mucosal immunity to ricin is best imparted by antibodies that target RTB’s high affinity Gal/GalNac recognition element in subdomain 2γ, not the low affinity Gal recognition domain in subdomain 1α.
Collapse
Affiliation(s)
- Yinghui Rong
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Greta Van Slyke
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - David J. Vance
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Jennifer Westfall
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Dylan Ehrbar
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Nicholas J. Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
- * E-mail:
| |
Collapse
|
21
|
Skakauskas V, Katauskis P. Modelling toxin effects on protein biosynthesis in eukaryotic cells. Comput Biol Chem 2017; 69:87-95. [PMID: 28599209 DOI: 10.1016/j.compbiolchem.2017.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 05/02/2017] [Accepted: 05/29/2017] [Indexed: 11/15/2022]
Abstract
We present a rather generic model for toxin (ricin) inhibition of protein biosynthesis in eukaryotic cells. We also study reduction of the ricin toxic effects with application of antibodies against the RTB subunit of ricin molecules. Both species initially are delivered extracellularly. The model accounts for the pinocytotic and receptor-mediated toxin endocytosis and the intact toxin exocytotic removal out of the cell. The model also includes the lysosomal toxin destruction, the intact toxin motion to the endoplasmic reticulum (ER) for separation of its molecules into the RTA and RTB subunits, and the RTA chain translocation into the cytosol. In the cytosol, one portion of the RTA undergoes degradation via the ERAD. The other its portion can inactivate ribosomes at a large rate. The model is based on a system of deterministic ODEs. The influence of the kinetic parameters on the protein concentration and antibody protection factor is studied in detail.
Collapse
Affiliation(s)
- Vladas Skakauskas
- Faculty of Mathematics and Informatics, Vilnius University, Naugarduko 24, 03225 Vilnius, Lithuania.
| | - Pranas Katauskis
- Faculty of Mathematics and Informatics, Vilnius University, Naugarduko 24, 03225 Vilnius, Lithuania
| |
Collapse
|
22
|
Noy-Porat T, Alcalay R, Epstein E, Sabo T, Kronman C, Mazor O. Extended therapeutic window for post-exposure treatment of ricin intoxication conferred by the use of high-affinity antibodies. Toxicon 2017; 127:100-105. [PMID: 28089771 DOI: 10.1016/j.toxicon.2017.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 01/09/2017] [Accepted: 01/10/2017] [Indexed: 12/24/2022]
Abstract
The plant toxin ricin is considered a potential bioterror agent against which there is no available antidote. To date, neutralizing antibodies are the most promising post-exposure treatment for ricin intoxication, yet so far they were shown to be effective only when given within several hours post exposure. As part of an ongoing effort to develop efficient ricin-countermeasures, we tested whether high-affinity antibodies that were previously isolated from immunized non-human primates, may confer effective post-exposure therapy for ricin-intoxicated mice treated at late time-points after exposure. While each antibody is capable of providing high protection rate by itself, a formulation consisting of three neutralizing antibodies that target different epitopes was tested to provide therapeutic coverage against different variants of the malicious pathogen. Indeed, the tri-antibody based cocktail was highly effective, its administration resulting in very high survival rates (>70%) when animals were treated as late as 48 h post exposure and significant protection (>30%) even at 72 h. This study establishes for the first time that anti-ricin antibodies can serve as a highly effective antidote at such late time-points after exposure. From the clinical point of view, the extended therapeutic window documented here is of high importance allowing adequate time to accurately identify the causative agent and may permit initiation of life-saving treatment with these antibodies even after the onset of clinical signs.
Collapse
Affiliation(s)
- Tal Noy-Porat
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Ron Alcalay
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Eyal Epstein
- Department of Biotechnology, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Tamar Sabo
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Chanoch Kronman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Ohad Mazor
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel.
| |
Collapse
|
23
|
Biological toxins of potential bioterrorism risk: Current status of detection and identification technology. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.05.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
24
|
Gupta N, Noël R, Goudet A, Hinsinger K, Michau A, Pons V, Abdelkafi H, Secher T, Shima A, Shtanko O, Sakurai Y, Cojean S, Pomel S, Liévin-Le Moal V, Leignel V, Herweg JA, Fischer A, Johannes L, Harrison K, Beard PM, Clayette P, Le Grand R, Rayner JO, Rudel T, Vacus J, Loiseau PM, Davey RA, Oswald E, Cintrat JC, Barbier J, Gillet D. Inhibitors of retrograde trafficking active against ricin and Shiga toxins also protect cells from several viruses, Leishmania and Chlamydiales. Chem Biol Interact 2016; 267:96-103. [PMID: 27712998 DOI: 10.1016/j.cbi.2016.10.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 08/09/2016] [Accepted: 10/03/2016] [Indexed: 11/25/2022]
Abstract
Medical countermeasures to treat biothreat agent infections require broad-spectrum therapeutics that do not induce agent resistance. A cell-based high-throughput screen (HTS) against ricin toxin combined with hit optimization allowed selection of a family of compounds that meet these requirements. The hit compound Retro-2 and its derivatives have been demonstrated to be safe in vivo in mice even at high doses. Moreover, Retro-2 is an inhibitor of retrograde transport that affects syntaxin-5-dependent toxins and pathogens. As a consequence, it has a broad-spectrum activity that has been demonstrated both in vitro and in vivo against ricin, Shiga toxin-producing O104:H4 entero-hemorrhagic E. coli and Leishmania sp. and in vitro against Ebola, Marburg and poxviruses and Chlamydiales. An effect is anticipated on other toxins or pathogens that use retrograde trafficking and syntaxin-5. Since Retro-2 targets cell components of the host and not directly the pathogen, no selection of resistant pathogens is expected. These lead compounds need now to be developed as drugs for human use.
Collapse
Affiliation(s)
- Neetu Gupta
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Romain Noël
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Amélie Goudet
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Karen Hinsinger
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Aurélien Michau
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Valérie Pons
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Hajer Abdelkafi
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | | | | | - Olena Shtanko
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | | | - Sandrine Cojean
- Antiparasitic Chemotherapy, UMR 8076, CNRS BioCIS, LabEx LERMIT, Université Paris-Sud, Université Paris-Saclay, F-92290, Chatenay-Malabry, France
| | - Sébastien Pomel
- Antiparasitic Chemotherapy, UMR 8076, CNRS BioCIS, LabEx LERMIT, Université Paris-Sud, Université Paris-Saclay, F-92290, Chatenay-Malabry, France
| | - Vanessa Liévin-Le Moal
- Antiparasitic Chemotherapy, UMR 8076, CNRS BioCIS, LabEx LERMIT, Université Paris-Sud, Université Paris-Saclay, F-92290, Chatenay-Malabry, France
| | - Véronique Leignel
- DRUGABILIS (French Research Performer SME), F-92290, Chatenay-Malabry, France
| | - Jo-Ana Herweg
- University of Würzburg, Biocenter, Chair of Microbiology, Am Hubland, D-97074, Würzburg, Germany
| | - Annette Fischer
- University of Würzburg, Biocenter, Chair of Microbiology, Am Hubland, D-97074, Würzburg, Germany
| | - Ludger Johannes
- Institut Curie, PSL Research University, Endocytic Trafficking and Therapeutic Delivery Group, 26 rue d'Ulm, F-75248, Paris Cedex 05, France; CNRS, UMR3666, F-75005, Paris, France; INSERM, U1143, F-75005, Paris, France
| | - Kate Harrison
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, United Kingdom
| | - Philippa M Beard
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG, United Kingdom; The Pirbright Institute, Ash Rd, Pirbright, Surrey GH24 0NF, United Kingdom
| | - Pascal Clayette
- ImmunoPharmacology and Biosafety Laboratory, BERTIN Pharma, CEA, F-92265, Fontenay-aux-Roses, France
| | - Roger Le Grand
- Institute of Emerging Diseases and Innovative Therapies, CEA, U1184, Immunology of Viral Infections and Autoimmune Diseases, Infectious Disease Models and Innovative Therapies Infrastructure, F-92265, Fontenay-aux-Roses, France; INSERM, U1184, F-94276, Le Kremlin-Bicêtre, France; University of Paris South, U1184, F-92265, Fontenay-aux-Roses, France; Vaccine Research Institute, Henri Mondor Hospital, F-94010, Créteil, France
| | - Jonathan O Rayner
- Infectious Disease Research, Southern Research, 2000 Ninth Avenue South, Birmingham, AL 35205, USA
| | - Thomas Rudel
- University of Würzburg, Biocenter, Chair of Microbiology, Am Hubland, D-97074, Würzburg, Germany
| | - Joël Vacus
- DRUGABILIS (French Research Performer SME), F-92290, Chatenay-Malabry, France
| | - Philippe M Loiseau
- Antiparasitic Chemotherapy, UMR 8076, CNRS BioCIS, LabEx LERMIT, Université Paris-Sud, Université Paris-Saclay, F-92290, Chatenay-Malabry, France
| | - Robert A Davey
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | | | - Jean-Christophe Cintrat
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Julien Barbier
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France
| | - Daniel Gillet
- Institute of Biology and Technology of Saclay (IBITECS), CEA, LabEx LERMIT, Université Paris-Saclay, F-91191, Gif Sur Yvette, France.
| |
Collapse
|
25
|
Vance DJ, Mantis NJ. Progress and challenges associated with the development of ricin toxin subunit vaccines. Expert Rev Vaccines 2016; 15:1213-22. [PMID: 26998662 PMCID: PMC5193006 DOI: 10.1586/14760584.2016.1168701] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The past several years have seen major advances in the development of a safe and efficacious ricin toxin vaccine, including the completion of two Phase I clinical trials with two different recombinant A subunit (RTA)-based vaccines: RiVax™ and RVEc™ adsorbed to aluminum salt adjuvant, as well as a non-human primate study demonstrating that parenteral immunization with RiVax elicits a serum antibody response that was sufficient to protect against a lethal dose aerosolized ricin exposure. One of the major obstacles moving forward is assessing vaccine efficacy in humans, when neither ricin-specific serum IgG endpoint titers nor toxin-neutralizing antibody levels are accepted as definitive predictors of protective immunity. In this review we summarize ongoing efforts to leverage recent advances in our understanding of RTA-antibody interactions at the structural level to develop novel assays to predict vaccine efficacy in humans.
Collapse
Affiliation(s)
- David J. Vance
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
| | - Nicholas J. Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, USA
- Department of Biomedical Sciences, University at Albany, Albany, New York, USA
| |
Collapse
|
26
|
Wang B, Lee CH, Johnson EL, Kluwe CA, Cunningham JC, Tanno H, Crooks RM, Georgiou G, Ellington AD. Discovery of high affinity anti-ricin antibodies by B cell receptor sequencing and by yeast display of combinatorial VH:VL libraries from immunized animals. MAbs 2016; 8:1035-44. [PMID: 27224530 DOI: 10.1080/19420862.2016.1190059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Ricin is a toxin that could potentially be used as a bioweapon. We identified anti-ricin A chain antibodies by sequencing the antibody repertoire from immunized mice and by selecting high affinity antibodies using yeast surface display. These methods led to the isolation of multiple antibodies with high (sub-nanomolar) affinity. Interestingly, the antibodies identified by the 2 independent approaches are from the same clonal lineages, indicating for the first time that yeast surface display can identify native antibodies. The new antibodies represent well-characterized reagents for biodefense diagnostics and therapeutics development.
Collapse
Affiliation(s)
- Bo Wang
- a Department of Chemical Engineering , University of Texas at Austin , Austin , TX , USA
| | - Chang-Han Lee
- a Department of Chemical Engineering , University of Texas at Austin , Austin , TX , USA
| | - Erik L Johnson
- a Department of Chemical Engineering , University of Texas at Austin , Austin , TX , USA
| | - Christien A Kluwe
- b Department of Molecular Biosciences , University of Texas at Austin , Austin , TX , USA
| | - Josephine C Cunningham
- b Department of Molecular Biosciences , University of Texas at Austin , Austin , TX , USA
| | - Hidetaka Tanno
- a Department of Chemical Engineering , University of Texas at Austin , Austin , TX , USA
| | - Richard M Crooks
- b Department of Molecular Biosciences , University of Texas at Austin , Austin , TX , USA
| | - George Georgiou
- a Department of Chemical Engineering , University of Texas at Austin , Austin , TX , USA.,b Department of Molecular Biosciences , University of Texas at Austin , Austin , TX , USA.,c Center for Systems and Synthetic Biology , University of Texas at Austin , Austin , TX , USA.,d Institute for Cellular and Molecular Biology , University of Texas at Austin , Austin , TX , USA.,e Department of Biomedical Engineering , University of Texas at Austin , Austin , TX , USA
| | - Andrew D Ellington
- b Department of Molecular Biosciences , University of Texas at Austin , Austin , TX , USA.,c Center for Systems and Synthetic Biology , University of Texas at Austin , Austin , TX , USA.,d Institute for Cellular and Molecular Biology , University of Texas at Austin , Austin , TX , USA
| |
Collapse
|
27
|
Yusibov V, Kushnir N, Streatfield SJ. Antibody Production in Plants and Green Algae. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:669-701. [PMID: 26905655 DOI: 10.1146/annurev-arplant-043015-111812] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Monoclonal antibodies (mAbs) have a wide range of modern applications, including research, diagnostic, therapeutic, and industrial uses. Market demand for mAbs is high and continues to grow. Although mammalian systems, which currently dominate the biomanufacturing industry, produce effective and safe recombinant mAbs, they have a limited manufacturing capacity and high costs. Bacteria, yeast, and insect cell systems are highly scalable and cost effective but vary in their ability to produce appropriate posttranslationally modified mAbs. Plants and green algae are emerging as promising production platforms because of their time and cost efficiencies, scalability, lack of mammalian pathogens, and eukaryotic posttranslational protein modification machinery. So far, plant- and algae-derived mAbs have been produced predominantly as candidate therapeutics for infectious diseases and cancer. These candidates have been extensively evaluated in animal models, and some have shown efficacy in clinical trials. Here, we review ongoing efforts to advance the production of mAbs in plants and algae.
Collapse
Affiliation(s)
- Vidadi Yusibov
- Fraunhofer USA Center for Molecular Biotechnology, Newark, Delaware 19711; , ,
| | - Natasha Kushnir
- Fraunhofer USA Center for Molecular Biotechnology, Newark, Delaware 19711; , ,
| | | |
Collapse
|
28
|
Noy-Porat T, Rosenfeld R, Ariel N, Epstein E, Alcalay R, Zvi A, Kronman C, Ordentlich A, Mazor O. Isolation of Anti-Ricin Protective Antibodies Exhibiting High Affinity from Immunized Non-Human Primates. Toxins (Basel) 2016; 8:toxins8030064. [PMID: 26950154 PMCID: PMC4810209 DOI: 10.3390/toxins8030064] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 11/16/2022] Open
Abstract
Ricin, derived from the castor bean plant Ricinus communis, is one of the most potent and lethal toxins known, against which there is no available antidote. To date, the use of neutralizing antibodies is the most promising post-exposure treatment for ricin intoxication. The aim of this study was to isolate high affinity anti-ricin antibodies that possess potent toxin-neutralization capabilities. Two non-human primates were immunized with either a ricin-holotoxin- or subunit-based vaccine, to ensure the elicitation of diverse high affinity antibodies. By using a comprehensive set of primers, immune scFv phage-displayed libraries were constructed and panned. A panel of 10 antibodies (five directed against the A subunit of ricin and five against the B subunit) was isolated and reformatted into a full-length chimeric IgG. All of these antibodies were found to neutralize ricin in vitro, and several conferred full protection to ricin-intoxicated mice when given six hours after exposure. Six antibodies were found to possess exceptionally high affinity toward the toxin, with KD values below pM (koff < 1 × 10−7 s−1) that were well correlated with their ability to neutralize ricin. These antibodies, alone or in combination, could be used for the development of a highly-effective therapeutic preparation for post-exposure treatment of ricin intoxication.
Collapse
Affiliation(s)
- Tal Noy-Porat
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Ronit Rosenfeld
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Naomi Ariel
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Eyal Epstein
- Department of Biotechnology, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Ron Alcalay
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Anat Zvi
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Chanoch Kronman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Arie Ordentlich
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| | - Ohad Mazor
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona 76100, Israel.
| |
Collapse
|
29
|
Simon S, Worbs S, Avondet MA, Tracz DM, Dano J, Schmidt L, Volland H, Dorner BG, Corbett CR. Recommended Immunological Assays to Screen for Ricin-Containing Samples. Toxins (Basel) 2015; 7:4967-86. [PMID: 26703725 PMCID: PMC4690108 DOI: 10.3390/toxins7124858] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/04/2015] [Accepted: 11/04/2015] [Indexed: 01/20/2023] Open
Abstract
Ricin, a toxin from the plant Ricinus communis, is one of the most toxic biological agents known. Due to its availability, toxicity, ease of production and absence of curative treatments, ricin has been classified by the Centers for Disease Control and Prevention (CDC) as category B biological weapon and it is scheduled as a List 1 compound in the Chemical Weapons Convention. An international proficiency test (PT) was conducted to evaluate detection and quantification capabilities of 17 expert laboratories. In this exercise one goal was to analyse the laboratories’ capacity to detect and differentiate ricin and the less toxic, but highly homologuous protein R. communis agglutinin (RCA120). Six analytical strategies are presented in this paper based on immunological assays (four immunoenzymatic assays and two immunochromatographic tests). Using these immunological methods “dangerous” samples containing ricin and/or RCA120 were successfully identified. Based on different antibodies used the detection and quantification of ricin and RCA120 was successful. The ricin PT highlighted the performance of different immunological approaches that are exemplarily recommended for highly sensitive and precise quantification of ricin.
Collapse
Affiliation(s)
- Stéphanie Simon
- CEA Saclay, Institute of Biology and Technologies of Saclay, Laboratory for Immunoanalytical Researches, Gif-sur-Yvette 91191 cedex, France.
| | - Sylvia Worbs
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Marc-André Avondet
- Federal Department of Defence, Civil Protection and Sport-SPIEZ Laboratory, Spiez 3700, Switzerland.
| | - Dobryan M Tracz
- Bacteriology & Enteric Diseases Division, National Microbiology Laboratory, Public Health Agency of Canada,Winnipeg, MB R3E 3R2, Canada.
| | - Julie Dano
- CEA Saclay, Institute of Biology and Technologies of Saclay, Laboratory for Immunoanalytical Researches, Gif-sur-Yvette 91191 cedex, France.
| | - Lisa Schmidt
- Bacteriology & Enteric Diseases Division, National Microbiology Laboratory, Public Health Agency of Canada,Winnipeg, MB R3E 3R2, Canada.
| | - Hervé Volland
- CEA Saclay, Institute of Biology and Technologies of Saclay, Laboratory for Immunoanalytical Researches, Gif-sur-Yvette 91191 cedex, France.
| | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany.
| | - Cindi R Corbett
- Bacteriology & Enteric Diseases Division, National Microbiology Laboratory, Public Health Agency of Canada,Winnipeg, MB R3E 3R2, Canada.
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, MB R3E 0J9, Canada.
| |
Collapse
|
30
|
Modeling of toxin-antibody interaction and toxin transport toward the endoplasmic reticulum. J Biol Phys 2015; 42:83-97. [PMID: 26306534 DOI: 10.1007/s10867-015-9394-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/14/2015] [Indexed: 01/04/2023] Open
Abstract
A model for toxin-antibody interaction and toxin trafficking towards the endoplasmic-reticulum is presented. Antibody and toxin (ricin) initially are delivered outside the cell. The model involves: the pinocytotic (cellular drinking) and receptor-mediated toxin internalization modes from the extracellular into the intracellular domain, its exocytotic excretion from the cytosol back to the extracellular medium, the intact toxin retrograde transport to the endoplasmic reticulum, the anterograde toxin movement outward from the cell across the plasma membrane, the lysosomal toxin degradation, and the toxin clearance (removal from the system) flux. The model consists of a set of coupled PDEs. Using an averaging procedure, the model is reduced to a system of coupled ODEs. Both PDEs and ODEs systems are solved numerically. Numerical results are illustrated by figures and discussed.
Collapse
|
31
|
Dong N, Luo L, Wu J, Jia P, Li Q, Wang Y, Gao Z, Peng H, Lv M, Huang C, Feng J, Li H, Shan J, Han G, Shen B. Monoclonal antibody, mAb 4C13, an effective detoxicant antibody against ricin poisoning. Vaccine 2015; 33:3836-42. [PMID: 26141013 DOI: 10.1016/j.vaccine.2015.06.096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/15/2015] [Accepted: 06/19/2015] [Indexed: 11/30/2022]
Abstract
Ricin is a glycoprotein produced in castor seeds and consists of two polypeptide chains named Ricin Toxin A Chain (RTA) and Ricin Toxin B Chain (RTB), linked via a disulfide bridge. Due to its high toxicity, ricin is regarded as a high terrorist risk for the public. However, antibodies can play a pivotal role in neutralizing the toxin. In this research, the anti-toxicant effect of mAb 4C13, a monoclonal antibody (mAb) established using detoxicated ricin as the immunized antigen, was evaluated. Compared with mAb 4F2 and mAb 5G6, the effective mechanism of mAb 4C13 was analyzed by experiments relating to its cytotoxicity, epitope on ricin, binding kinetics with the toxin, its blockage on the protein synthesis inhibition induced by ricin and the intracelluar tracing of its complex with ricin. Our result indicated that mAb 4C13 could recognize and bind to RTA, RTB and exert its high affinity to the holotoxin. Both cytotoxicity and animal toxicity of ricin were well blocked by pre-incubating the toxin with mAb 4C13. By intravenous injection, mAb 4C13 could rescue the mouse intraperitoneally (ip) injected with a lethal dose of ricin (20μg/kg) even at 6h after the intoxication and its efficacy was dependent on its dosage. This research indicated that mAb 4C13 could be an excellent candidate for therapeutic antibodies. Its potent antitoxic efficiency was related to its recognition on the specific epitope with very high affinity and its blockage of protein synthesis inhibition in cytoplasm followed by cellular internalization with ricin.
Collapse
Affiliation(s)
- Na Dong
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Longlong Luo
- Beijing Institute of Basic Medical Sciences, Beijing 100850, China
| | - Junhua Wu
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Peiyuan Jia
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Qian Li
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China; Beijing Institute of Basic Medical Sciences, Beijing 100850, China
| | - Yuxia Wang
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China.
| | - Zhongcai Gao
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Hui Peng
- Beijing Institute of Basic Medical Sciences, Beijing 100850, China
| | - Ming Lv
- Beijing Institute of Basic Medical Sciences, Beijing 100850, China
| | - Chunqian Huang
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Jiannan Feng
- Beijing Institute of Basic Medical Sciences, Beijing 100850, China.
| | - Hua Li
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Junjie Shan
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Gang Han
- Beijing Institute of Pharmacology and Toxicology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing 100850, China
| | - Beifen Shen
- Beijing Institute of Basic Medical Sciences, Beijing 100850, China
| |
Collapse
|
32
|
Dupré M, Gilquin B, Fenaille F, Feraudet-Tarisse C, Dano J, Ferro M, Simon S, Junot C, Brun V, Becher F. Multiplex Quantification of Protein Toxins in Human Biofluids and Food Matrices Using Immunoextraction and High-Resolution Targeted Mass Spectrometry. Anal Chem 2015; 87:8473-80. [DOI: 10.1021/acs.analchem.5b01900] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Mathieu Dupré
- CEA, DSV, iBiTec-S, Laboratoire d’études
du métabolisme des médicaments, 91191 Gif-sur-Yvette, France
| | - Benoit Gilquin
- Université
Grenoble Alpes, iRTSV-BGE, F-38000 Grenoble, France
- CEA, iRTSV-BGE, F-38000 Grenoble, France
- INSERM, BGE, F-38000 Grenoble, France
| | - François Fenaille
- CEA, DSV, iBiTec-S, Laboratoire d’études
du métabolisme des médicaments, 91191 Gif-sur-Yvette, France
| | - Cécile Feraudet-Tarisse
- CEA, DSV, iBiTec-S, Laboratoire d’études
et de recherches en immunoanalyse, 91191 Gif-sur-Yvette, France
| | - Julie Dano
- CEA, DSV, iBiTec-S, Laboratoire d’études
et de recherches en immunoanalyse, 91191 Gif-sur-Yvette, France
| | - Myriam Ferro
- Université
Grenoble Alpes, iRTSV-BGE, F-38000 Grenoble, France
- CEA, iRTSV-BGE, F-38000 Grenoble, France
- INSERM, BGE, F-38000 Grenoble, France
| | - Stéphanie Simon
- CEA, DSV, iBiTec-S, Laboratoire d’études
et de recherches en immunoanalyse, 91191 Gif-sur-Yvette, France
| | - Christophe Junot
- CEA, DSV, iBiTec-S, Laboratoire d’études
du métabolisme des médicaments, 91191 Gif-sur-Yvette, France
| | - Virginie Brun
- Université
Grenoble Alpes, iRTSV-BGE, F-38000 Grenoble, France
- CEA, iRTSV-BGE, F-38000 Grenoble, France
- INSERM, BGE, F-38000 Grenoble, France
| | - François Becher
- CEA, DSV, iBiTec-S, Laboratoire d’études
du métabolisme des médicaments, 91191 Gif-sur-Yvette, France
| |
Collapse
|
33
|
Antibody treatment against pulmonary exposure to abrin confers significantly higher levels of protection than treatment against ricin intoxication. Toxicol Lett 2015; 237:72-8. [PMID: 26051443 DOI: 10.1016/j.toxlet.2015.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/14/2015] [Accepted: 06/02/2015] [Indexed: 11/22/2022]
Abstract
Abrin, a potent plant-derived toxin bearing strong resemblance to ricin, irreversibly inactivates ribosomes by site-specific depurination, thereby precipitating cessation of protein synthesis in cells. Due to its high availability and ease of preparation, abrin is considered a biological threat, especially in context of bioterror warfare. To date, there is no established therapeutic countermeasure against abrin intoxication. In the present study, we examined the progress of pulmonary abrin intoxication in mice, evaluated the protective effect of antibody-based post-exposure therapy, and compared these findings to those observed for ricin intoxication and therapy. Salient features of abrin intoxication were found to be similar to those of ricin and include massive recruitment of neutrophils to the lungs, high levels of pro-inflammatory markers in the bronchoalveolar lavage fluid and damage of the alveolar-capillary barrier. In contrast, the protective effect of anti-abrin antibody treatment was found to differ significantly from that of anti-ricin treatment. While anti-ricin treatment efficiency was quite limited even at 24h post-exposure (34% protection), administration of polyclonal anti-abrin antibodies even as late as 72h post-exposure, conferred exceedingly high-level protection (>70%). While both anti-toxin antibody treatments caused neutrophil and macrophage levels in the lungs to revert to normal, only anti-abrin treatment brought about a significant decline in the pulmonary levels of the pro-inflammatory cytokine IL-6. The differential ability of the anti-toxin treatments to dampen inflammation caused by the two similar toxins, abrin and ricin, could explain the radically different levels of protection achieved following antibody treatment.
Collapse
|
34
|
Diamant E, Torgeman A, Ozeri E, Zichel R. Monoclonal Antibody Combinations that Present Synergistic Neutralizing Activity: A Platform for Next-Generation Anti-Toxin Drugs. Toxins (Basel) 2015; 7:1854-81. [PMID: 26035486 PMCID: PMC4488679 DOI: 10.3390/toxins7061854] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 05/07/2015] [Accepted: 05/19/2015] [Indexed: 12/25/2022] Open
Abstract
Monoclonal antibodies (MAbs) are among the fastest-growing therapeutics and are being developed for a broad range of indications, including the neutralization of toxins, bacteria and viruses. Nevertheless, MAbs potency is still relatively low when compared to conventional polyclonal Ab preparations. Moreover, the efficacy of an individual neutralizing MAb may significantly be hampered by the potential absence or modification of its target epitope in a mutant or subtype of the infectious agent. These limitations of individual neutralizing MAbs can be overcome by using oligoclonal combinations of several MAbs with different specificities to the target antigen. Studies conducted in our lab and by others show that such combined MAb preparation may present substantial synergy in its potency over the calculated additive potency of its individual MAb components. Moreover, oligoclonal preparation is expected to be better suited to compensating for reduced efficacy due to epitope variation. In this review, the synergistic neutralization properties of combined oligoclonal Ab preparations are described. The effect of Ab affinity, autologous Fc fraction, and targeting a critical number of epitopes, as well as the unexpected contribution of non-neutralizing clones to the synergistic neutralizing effect are presented and discussed.
Collapse
Affiliation(s)
- Eran Diamant
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Amram Torgeman
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Eyal Ozeri
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| | - Ran Zichel
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel.
| |
Collapse
|
35
|
Rapid assessment of antibody-induced ricin neutralization by employing a novel functional cell-based assay. J Immunol Methods 2015; 424:136-9. [PMID: 26003675 DOI: 10.1016/j.jim.2015.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/13/2015] [Accepted: 05/13/2015] [Indexed: 11/22/2022]
Abstract
Ricin is one of the most potent and lethal toxins known against which there is no available antidote. Currently, the most promising countermeasures against the toxin are based on neutralizing antibodies elicited by active vaccination or administered passively. A cell-based assay is widely applied for the primary screening and evaluation of anti-ricin antibodies, yet such assays are usually time-consuming (18-72 h). Here, we report of a novel assay to monitor ricin activity, based on HeLa cells that stably express the rapidly-degraded ubiquitin-luciferase (Ub-FL, half-life of 2 min). Ricin-induced arrest of protein synthesis could be quantified within 3 to 6h post intoxication (IC90 of 300 and 100 ng/ml, respectively). Furthermore, by stabilizing the intracellular levels of Ub-FL in the last hour of the assay, a 3-fold increase in the assay sensitivity was attained. We applied this assay to monitor the efficacy of a ricin holotoxin-based vaccine by measuring the formation of neutralizing antibodies throughout the immunization course. The potency of anti-ricin monoclonal antibodies (directed to either subunit of the toxin) could also be easily and accurately measured in this assay format. Owing to its simplicity, this assay may be implemented for high-throughput screening of ricin-neutralizing antibodies and for identification of small-molecule inhibitors of the toxin, as well as other ribosome-inactivating toxins.
Collapse
|
36
|
Skakauskas V, Katauskis P, Skvortsov A, Gray P. Toxin effect on protein biosynthesis in eukaryotic cells: a simple kinetic model. Math Biosci 2015; 261:83-90. [PMID: 25572165 DOI: 10.1016/j.mbs.2014.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 12/24/2014] [Accepted: 12/26/2014] [Indexed: 10/24/2022]
Abstract
A model for toxin inhibition of protein synthesis inside eukaryotic cells is presented. Mitigation of this effect by introduction of an antibody is also studied. Antibody and toxin (ricin) initially are delivered outside the cell. The model describes toxin internalization from the extracellular into the intracellular domain, its transport to the endoplasmic reticulum (ER) and the cleavage inside the ER into the RTA and RTB chains, the release of RTA into the cytosol, inactivation (depurination) of ribosomes, and the effect on translation. The model consists of a set of ODEs which are solved numerically. Numerical results are illustrated by figures and discussed.
Collapse
Affiliation(s)
- Vladas Skakauskas
- Faculty of Mathematics and Informatics, Vilnius University, Naugarduko 24, Vilnius 03225, Lithuania.
| | - Pranas Katauskis
- Faculty of Mathematics and Informatics, Vilnius University, Naugarduko 24, Vilnius 03225, Lithuania
| | - Alex Skvortsov
- Defence Science and Technology Organisation, 506 Lorimer st., Melbourne, VIC 3207, Australia
| | - Peter Gray
- Defence Science and Technology Organisation, 506 Lorimer st., Melbourne, VIC 3207, Australia
| |
Collapse
|
37
|
Dutta K, Varshney AK, Franklin MC, Goger M, Wang X, Fries BC. Mechanisms mediating enhanced neutralization efficacy of staphylococcal enterotoxin B by combinations of monoclonal antibodies. J Biol Chem 2015; 290:6715-30. [PMID: 25572397 DOI: 10.1074/jbc.m114.630715] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Staphylococcal enterotoxin B (SEB) is a superantigen that cross-links the major histocompatibility complex class II and specific V-β chains of the T-cell receptor, thus forming a ternary complex. Developing neutralizing mAb to disrupt the ternary complex and abrogate the resulting toxicity is a major therapeutic challenge because SEB is effective at very low concentrations. We show that combining two SEB-specific mAbs enhances their efficacy, even though one of the two mAbs by itself has no effect on neutralization. Crystallography was employed for fine-mapping conformational epitopes in binary and ternary complexes between SEB and Fab fragments. NMR spectroscopy was used to validate and identify subtle allosteric changes induced by mAbs binding to SEB. The mapping of epitopes established that a combination of different mAbs can enhance efficacy of mAb-mediated protection from SEB induced lethal shock by two different mechanisms: one mAb mixture promoted clearance of the toxin both in vitro and in vivo by FcR-mediated cross-linking and clearance, whereas the other mAb mixture induced subtle allosteric conformational changes in SEB that perturbed formation of the SEB·T-cell receptor·major histocompatibility complex class II trimer. Finally structural information accurately predicted mAb binding to other superantigens that share conformational epitopes with SEB. Fine mapping of conformational epitopes is a powerful tool to establish the mechanism and optimize the action of synergistic mAb combinations.
Collapse
Affiliation(s)
- Kaushik Dutta
- From the New York Structural Biology Center, New York, New York 10027,
| | - Avanish K Varshney
- the Department of Medicine and Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11790, and the Department of Medicine, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461
| | | | - Michael Goger
- From the New York Structural Biology Center, New York, New York 10027
| | - Xiaobo Wang
- the Department of Medicine, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Bettina C Fries
- the Department of Medicine and Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11790, and the Department of Medicine, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461
| |
Collapse
|
38
|
Abrin and Ricin: Understanding Their Toxicity, Diagnosis, and Treatment. BIOLOGICAL TOXINS AND BIOTERRORISM 2015. [DOI: 10.1007/978-94-007-5869-8_1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
|
39
|
Characterization and epitope mapping of the polyclonal antibody repertoire elicited by ricin holotoxin-based vaccination. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:1534-40. [PMID: 25209559 DOI: 10.1128/cvi.00510-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ricin, one of the most potent and lethal toxins known, is classified by the Centers for Disease Control and Prevention (CDC) as a select agent. Currently, there is no available antidote against ricin exposure, and the most promising therapy is based on neutralizing antibodies elicited by active vaccination or that are given passively. The aim of this study was to characterize the repertoire of anti-ricin antibodies generated in rabbits immunized with ricin toxoid. These anti-ricin antibodies exhibit an exceptionally high avidity (thiocyanate-based avidity index, 9 M) toward ricin and an apparent affinity of 1 nM. Utilizing a novel tissue culture-based assay that enables the determination of ricin activity within a short time period, we found that the anti-ricin antibodies also possess a very high neutralizing titer. In line with these findings, these antibodies conferred mice with full protection against pulmonary ricinosis when administered as a passive vaccination. Epitope mapping analysis using phage display random peptide libraries revealed that the polyclonal serum contains four immunodominant epitopes, three of which are located on the A subunit and one on the B subunit of ricin. Only two of the four epitopes were found to have a significant role in ricin neutralization. To the best of our knowledge, this is the first work that characterizes these immunological aspects of the polyclonal response to ricin holotoxin-based vaccination. These findings provide useful information and a possible strategy for the development and design of an improved ricin holotoxin-based vaccine.
Collapse
|
40
|
Herrera C, Vance DJ, Eisele LE, Shoemaker CB, Mantis NJ. Differential neutralizing activities of a single domain camelid antibody (VHH) specific for ricin toxin's binding subunit (RTB). PLoS One 2014; 9:e99788. [PMID: 24918772 PMCID: PMC4053406 DOI: 10.1371/journal.pone.0099788] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 05/17/2014] [Indexed: 11/18/2022] Open
Abstract
Ricin, a member of the A-B family of ribosome-inactivating proteins, is classified as a Select Toxin by the Centers for Disease Control and Prevention because of its potential use as a biothreat agent. In an effort to engineer therapeutics for ricin, we recently produced a collection of alpaca-derived, heavy-chain only antibody VH domains (VHH or “nanobody”) specific for ricin’s enzymatic (RTA) and binding (RTB) subunits. We reported that one particular RTB-specific VHH, RTB-B7, when covalently linked via a peptide spacer to different RTA-specific VHHs, resulted in heterodimers like VHH D10/B7 that were capable of passively protecting mice against a lethal dose challenge with ricin. However, RTB-B7 itself, when mixed with ricin at a 1∶10 toxin:antibody ratio did not afford any protection in vivo, even though it had demonstrable toxin-neutralizing activity in vitro. To better define the specific attributes of antibodies associated with ricin neutralization in vitro and in vivo, we undertook a more thorough characterization of RTB-B7. We report that RTB-B7, even at 100-fold molar excess (toxin:antibody) was unable to alter the toxicity of ricin in a mouse model. On the other hand, in two well-established cytotoxicity assays, RTB-B7 neutralized ricin with a 50% inhibitory concentration (IC50) that was equivalent to that of 24B11, a well-characterized and potent RTB-specific murine monoclonal antibody. In fact, RTB-B7 and 24B11 were virtually identical when compared across a series of in vitro assays, including adherence to and neutralization of ricin after the toxin was pre-bound to cell surface receptors. RTB-B7 differed from both 24B11 and VHH D10/B7 in that it was relatively less effective at blocking ricin attachment to receptors on host cells and was not able to form high molecular weight toxin:antibody complexes in solution. Whether either of these activities is important in ricin toxin neutralizing activity in vivo remains to be determined.
Collapse
Affiliation(s)
- Cristina Herrera
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
| | - David J. Vance
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Leslie E. Eisele
- Scientific Cores, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Charles B. Shoemaker
- Department of Infectious Disease and Global Health, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachusetts, United States of America
| | - Nicholas J. Mantis
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
- * E-mail:
| |
Collapse
|
41
|
Kinetic Characterization of a Panel of High-Affinity Monoclonal Antibodies Targeting Ricin and Recombinant Re-Formatting for Biosensor Applications. Antibodies (Basel) 2014. [DOI: 10.3390/antib3020215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
42
|
Abstract
Ricin is a member of the ubiquitous family of plant and bacterial AB toxins that gain entry into the cytosol of host cells through receptor-mediated endocytosis and retrograde traffic through the trans-Golgi network (TGN) and endoplasmic reticulum (ER). While a few ricin toxin-specific neutralizing monoclonal antibodies (MAbs) have been identified, the mechanisms by which these antibodies prevent toxin-induced cell death are largely unknown. Using immunofluorescence confocal microscopy and a TGN-specific sulfation assay, we demonstrate that 24B11, a MAb against ricin’s binding subunit (RTB), associates with ricin in solution or when prebound to cell surfaces and then markedly enhances toxin uptake into host cells. Following endocytosis, however, toxin-antibody complexes failed to reach the TGN; instead, they were shunted to Rab7-positive late endosomes and LAMP-1-positive lysosomes. Monovalent 24B11 Fab fragments also interfered with toxin retrograde transport, indicating that neither cross-linking of membrane glycoproteins/glycolipids nor the recently identified intracellular Fc receptor is required to derail ricin en route to the TGN. Identification of the mechanism(s) by which antibodies like 24B11 neutralize ricin will advance our fundamental understanding of protein trafficking in mammalian cells and may lead to the discovery of new classes of toxin inhibitors and therapeutics for biodefense and emerging infectious diseases. Ricin is the prototypic member of the AB family of medically important plant and bacterial toxins that includes cholera and Shiga toxins. Ricin is also a category B biothreat agent. Despite ongoing efforts to develop vaccines and antibody-based therapeutics against ricin, very little is known about the mechanisms by which antibodies neutralize this toxin. In general, it is thought that antibodies simply prevent toxins from attaching to cell surface receptors or promote their clearance through Fc receptor (FcR)-mediated uptake. In this report, however, we describe a neutralizing monoclonal antibody (MAb) against ricin’s binding subunit (RTB) that not only associates with ricin after the toxin has bound to the cell’s surface but actually enhances toxin uptake into host cells. Following endocytosis, the antibody-toxin complexes are then routed for degradation. The results of this study are important because they reveal a previously unappreciated role for B-subunit-specific antibodies in intracellular neutralization of ricin toxin.
Collapse
|
43
|
Skakauskas V, Katauskis P, Skvortsov A, Gray P. Modelling effects of internalized antibody: a simple comparative study. Theor Biol Med Model 2014; 11:11. [PMID: 24521456 PMCID: PMC3976039 DOI: 10.1186/1742-4682-11-11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 01/31/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The modelling framework is proposed to study protection properties of antibodies to neutralize the effects of the plant toxin (ricin). The present study extends our previous work by including (i) the model of intracellular transport of toxin to the Endoplasmic Reticulum and (ii) the model of the internalised antibodies (when antibody is delivered directly into the cytosol). METHOD Simulation of the receptor-toxin-antibody interaction is implemented by solving the systems of PDEs (advection-diffusion models) or ODEs (rate models) for the underlying transport coupled with mass-action kinetics. RESULTS As the main application of the enhanced framework we present a comparative study of two kinds (external and internalised) of antibodies. This comparison is based on calculation of the non-dimensional protection factor using the same set of parameters (geometry, binding constants, initial concentrations of species, and total initial amount of the antibody). CONCLUSION This research will provide a framework for consistent evaluation and comparison of different types of antibodies for toxicological applications.
Collapse
Affiliation(s)
| | | | - Alex Skvortsov
- Defence Science and Technology Organisation, 506 Lorimer st,, VIC 3207 Melbourne, Australia.
| | | |
Collapse
|
44
|
Hu CC, Yin J, Chau D, Cherwonogrodzky JW, Hu WG. Active immunity induced by passive IgG post-exposure protection against ricin. Toxins (Basel) 2014; 6:380-93. [PMID: 24451844 PMCID: PMC3920268 DOI: 10.3390/toxins6010380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 01/10/2014] [Accepted: 01/10/2014] [Indexed: 11/16/2022] Open
Abstract
Therapeutic antibodies can confer an instant protection against biothreat agents when administered. In this study, intact IgG and F(ab')2 from goat anti-ricin hyperimmune sera were compared for the protection against lethal ricin mediated intoxication. Similar ricin-binding affinities and neutralizing activities in vitro were observed between IgG and F(ab')2 when compared at the same molar concentration. In a murine ricin intoxication model, both IgG and F(ab')2 could rescue 100% of the mice by one dose (3 nmol) administration of antibodies 1 hour after 5 × LD50 ricin challenge. Nine days later, when the rescued mice received a second ricin challenge (5 × LD50), only the IgG-treated mice survived; the F(ab')2-treated mice did not. The experimental design excluded the possibility of residual goat IgG responsible for the protection against the second ricin challenge. Results confirmed that the active immunity against ricin in mice was induced quickly following the passive delivery of a single dose of goat IgG post-exposure. Furthermore, it was demonstrated that the induced active immunity against ricin in mice lasted at least 5 months. Therefore, passive IgG therapy not only provides immediate protection to the victim after ricin exposure, but also elicits an active immunity against ricin that subsequently results in long term protection.
Collapse
Affiliation(s)
- Charles Chen Hu
- Defence Research and Development Canada-Suffield, Box 4000, Station Main, Medicine Hat, AB T1A 8K6, Canada.
| | - Junfei Yin
- Defence Research and Development Canada-Suffield, Box 4000, Station Main, Medicine Hat, AB T1A 8K6, Canada.
| | - Damon Chau
- Defence Research and Development Canada-Suffield, Box 4000, Station Main, Medicine Hat, AB T1A 8K6, Canada.
| | - John W Cherwonogrodzky
- Defence Research and Development Canada-Suffield, Box 4000, Station Main, Medicine Hat, AB T1A 8K6, Canada.
| | - Wei-Gang Hu
- Defence Research and Development Canada-Suffield, Box 4000, Station Main, Medicine Hat, AB T1A 8K6, Canada.
| |
Collapse
|
45
|
Bagaria S, Ponnalagu D, Bisht S, Karande AA. Mechanistic insights into the neutralization of cytotoxic abrin by the monoclonal antibody D6F10. PLoS One 2013; 8:e70273. [PMID: 23922965 PMCID: PMC3726390 DOI: 10.1371/journal.pone.0070273] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 06/14/2013] [Indexed: 01/06/2023] Open
Abstract
Abrin, an A/B toxin obtained from the Abrus precatorius plant is extremely toxic and a potential bio-warfare agent. Till date there is no antidote or vaccine available against this toxin. The only known neutralizing monoclonal antibody against abrin, namely D6F10, has been shown to rescue the toxicity of abrin in cells as well as in mice. The present study focuses on mapping the epitopic region to understand the mechanism of neutralization of abrin by the antibody D6F10. Truncation and mutational analysis of abrin A chain revealed that the amino acids 74-123 of abrin A chain contain the core epitope and the residues Thr112, Gly114 and Arg118 are crucial for binding of the antibody. In silico analysis of the position of the mapped epitope indicated that it is present close to the active site cleft of abrin A chain. Thus, binding of the antibody near the active site blocks the enzymatic activity of abrin A chain, thereby rescuing inhibition of protein synthesis by the toxin in vitro. At 1∶10 molar concentration of abrin:antibody, the antibody D6F10 rescued cells from abrin-mediated inhibition of protein synthesis but did not prevent cell attachment of abrin. Further, internalization of the antibody bound to abrin was observed in cells by confocal microscopy. This is a novel finding which suggests that the antibody might function intracellularly and possibly explains the rescue of abrin's toxicity by the antibody in whole cells and animals. To our knowledge, this study is the first report on a neutralizing epitope for abrin and provides mechanistic insights into the poorly understood mode of action of anti-A chain antibodies against several toxins including ricin.
Collapse
Affiliation(s)
- Shradha Bagaria
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | | | | | | |
Collapse
|
46
|
O'Hara JM, Mantis NJ. Neutralizing monoclonal antibodies against ricin's enzymatic subunit interfere with protein disulfide isomerase-mediated reduction of ricin holotoxin in vitro. J Immunol Methods 2013; 395:71-8. [PMID: 23774033 DOI: 10.1016/j.jim.2013.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 05/26/2013] [Accepted: 06/06/2013] [Indexed: 11/15/2022]
Abstract
The penultimate event in the intoxication of mammalian cells by ricin toxin is the reduction, in the endoplasmic reticulum (ER), of the intermolecular disulfide bond that links ricin's enzymatic (RTA) and binding (RTB) subunits. In this report we adapted an in vitro protein disulfide isomerase (PDI)-mediated reduction assay to test the hypothesis that the RTA-specific neutralizing monoclonal antibody (mAb) IB2 interferes with the liberation of RTA from RTB. IB2 recognizes an epitope located near the interface between RTA and RTB and, like a number of other RTA-specific neutralizing mAbs, is proposed to neutralize ricin intracellularly. In this study, we found that IB2 virtually eliminated the reduction of ricin holotoxin into RTA and RTB in vitro. Surprisingly, three other neutralizing mAbs (GD12, R70 and SyH7) that bind epitopes at considerable distance from ricin's disulfide bond were as effective (or nearly as effective) as IB2 in interfering with PDI-mediated liberation of RTA from RTB. By contrast, two non-neutralizing RTA-specific mAbs, FGA12 and SB1, did not affect PDI-mediated reduction of ricin. These data reveal a possible mechanism by which RTA-specific antibodies may neutralize ricin intracellularly, provided they are capable of trafficking in association with ricin from the cell surface to the ER.
Collapse
Affiliation(s)
- Joanne M O'Hara
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States
| | | |
Collapse
|
47
|
A simple model for assessment of anti-toxin antibodies. BIOMED RESEARCH INTERNATIONAL 2013; 2013:230906. [PMID: 23862138 PMCID: PMC3687717 DOI: 10.1155/2013/230906] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 05/20/2013] [Indexed: 01/15/2023]
Abstract
The toxins associated with infectious diseases are potential targets for inhibitors which have the potential for prophylactic or therapeutic use. Many antibodies have been generated for this purpose, and the objective of this study was to develop a simple mathematical model that may be used to evaluate the potential protective effect of antibodies. This model was used to evaluate the contributions of antibody affinity and concentration to reducing antibody-receptor complex formation and internalization. The model also enables prediction of the antibody kinetic constants and concentration required to provide a specified degree of protection. We hope that this model, once validated experimentally, will be a useful tool for in vitro selection of potentially protective antibodies for progression to in vivo evaluation.
Collapse
|
48
|
Pathogen-free screening of bacteria-specific hybridomas for selecting high-quality monoclonal antibodies against pathogen bacteria as illustrated for Legionella pneumophila. J Immunol Methods 2013; 391:81-94. [PMID: 23454033 DOI: 10.1016/j.jim.2013.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 02/19/2013] [Accepted: 02/21/2013] [Indexed: 11/20/2022]
Abstract
Antibodies are potent biological tools increasingly used as detection, diagnostic and therapeutic reagents. Many technological advances have optimized and facilitated production and screening of monoclonal antibodies. We report here an original method to screen for antibodies targeting biosafety level 2 or 3 pathogens without the fastidious handling inherent to pathogen use. A double ELISA screening was performed using as coated antigen transformed Escherichia coli expressing at its surface a protein specific to the pathogenic bacteria versus control untransformed E. coli. This method was applied to Legionella, using the surface-exposed Mip protein (macrophage infectivity potentiator). This screening proved to be an excellent means of selecting mAbs that bind Legionella pneumophila 1 surface-exposed Mip protein. This method also appears more biologically relevant than screening using the recombinant Mip protein alone and less tedious than a test performed directly on Legionella bacteria. We obtained 21 mAbs that bind strongly to L. pneumophila serogroups 1 to 13, and we validated their use in a rapid ELISA (performed in 4.5 h) and an immunochromatographic test (20 min).
Collapse
|
49
|
Conformation-dependent high-affinity potent ricin-neutralizing monoclonal antibodies. BIOMED RESEARCH INTERNATIONAL 2012; 2013:471346. [PMID: 23484120 PMCID: PMC3591125 DOI: 10.1155/2013/471346] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 10/26/2012] [Accepted: 11/10/2012] [Indexed: 12/23/2022]
Abstract
Ricin is a potential biothreat agent with no approved antidote available for ricin poisoning. The aim of this study was to develop potent antibody-based antiricin antidotes. Four strong ricin resistant hybridoma clones secreting antiricin monoclonal antibodies (mAbs) were developed. All four mAbs are bound to conformational epitopes of ricin toxin B (RTB) with high affinity (KD values from 2.55 to 36.27 nM). RTB not only triggers cellular uptake of ricin, but also facilitates transport of the ricin toxin A (RTA) from the endoplasmic reticulum to the cytosol, where RTA exerts its toxic activity. The four mAbs were found to have potent ricin-neutralizing capacities and synergistic effects among them as determined by an in vitro neutralization assay. In vivo protection assay demonstrated that all four mAbs had strong efficacy against ricin challenges. D9 was found to be exceptionally effective. Intraperitoneal (i.p.) administration of D9, at a dose of 5 μ g, 6 weeks before or 6 hours after an i.p. challenge with 5 × LD50 of ricin was able to protect or rescue 100% of the mice, indicating that mAb D9 is an excellent candidate to be developed as a potent antidote against ricin poisoning for both prophylactic and therapeutic purposes.
Collapse
|
50
|
Hu WG, Yin J, Chau D, Negrych LM, Cherwonogrodzky JW. Humanization and characterization of an anti-ricin neutralization monoclonal antibody. PLoS One 2012; 7:e45595. [PMID: 23049820 PMCID: PMC3458913 DOI: 10.1371/journal.pone.0045595] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/21/2012] [Indexed: 01/02/2023] Open
Abstract
Ricin is regarded as a high terrorist risk for the public due to its high toxicity and ease of production. Currently, there is no therapeutic or vaccine available against ricin. D9, a murine monoclonal antibody developed previously in our laboratory, can strongly neutralize ricin and is therefore a good candidate for humanization. Humanization of D9 variable regions was achieved by a complementarity-determining region grafting approach. The humanized D9 (hD9) variable regions were further grafted onto human heavy and light chain constant regions to assemble the complete antibody gene. A foot-and-mouth-disease virus-derived 2A self-processing sequence was introduced between heavy and light chain DNA sequences to cleave the recombinant protein into a functional full-length antibody molecule from a single open reading frame driven by a single promoter in an adenoviral vector. After expression in mammalian cells and purification, the hD9 was demonstrated to have equimolar expression of the full-length antibody heavy and light chains. More importantly, the hD9 exhibited high affinity to ricin with KD of 1.63 nM, comparable to its parental murine D9 (2.55 nM). In a mouse model, intraperitoneal (i.p.) administration of hD9, at a low dose of 5 µg per mouse, 4 hours after the i.p. challenge with 5×LD50 ricin was found to rescue 100% of the mice. In addition, administered 6 hours post-challenge, hD9 could still rescue 50% of the mice. The hD9 has the potential to be used for prophylactic or therapeutic purposes against ricin poisoning.
Collapse
MESH Headings
- Adenoviridae/genetics
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal, Humanized/genetics
- Antibodies, Monoclonal, Humanized/immunology
- Antibodies, Monoclonal, Humanized/pharmacokinetics
- Antibodies, Monoclonal, Humanized/therapeutic use
- Antibody Affinity
- Antitoxins/genetics
- Antitoxins/immunology
- Antitoxins/therapeutic use
- Chemical Warfare Agents/poisoning
- Complementarity Determining Regions/genetics
- Complementarity Determining Regions/immunology
- DNA, Viral/genetics
- DNA, Viral/metabolism
- Female
- Foot-and-Mouth Disease Virus/genetics
- Genetic Vectors
- Half-Life
- Humans
- Immunoglobulin Heavy Chains/genetics
- Immunoglobulin Heavy Chains/immunology
- Immunoglobulin Light Chains/genetics
- Immunoglobulin Light Chains/immunology
- Injections, Intraperitoneal
- Mice
- Models, Molecular
- Molecular Sequence Data
- Plant Poisoning/immunology
- Plant Poisoning/mortality
- Plant Poisoning/prevention & control
- Protein Engineering
- Ricin/poisoning
- Survival Rate
Collapse
Affiliation(s)
- Wei-Gang Hu
- Defence Research and Development Canada - Suffield, Medicine Hat, Alberta, Canada.
| | | | | | | | | |
Collapse
|