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Tiano SML, Landi N, Marano V, Ragucci S, Bianco G, Cacchiarelli D, Swuec P, Silva M, De Cegli R, Sacco F, Di Maro A, Cortese M. Quinoin, type 1 ribosome inactivating protein alters SARS-CoV-2 viral replication organelle restricting viral replication and spread. Int J Biol Macromol 2024:135700. [PMID: 39288862 DOI: 10.1016/j.ijbiomac.2024.135700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 09/09/2024] [Accepted: 09/13/2024] [Indexed: 09/19/2024]
Abstract
SARS-CoV-2 pandemic clearly demonstrated the lack of preparation against novel and emerging viral diseases. This prompted an enormous effort to identify antiviral to curb viral spread and counteract future pandemics. Ribosome Inactivating Proteins (RIPs) and Ribotoxin-Like Proteins (RL-Ps) are toxin enzymes isolated from edible plants and mushrooms, both able to inactivate protein biosynthesis. In the present study, we combined imaging analyses, transcriptomic and proteomic profiling to deeper investigate the spectrum of antiviral activity of quinoin, type 1 RIP from quinoa seeds. Here, we show that RIPs, but not RL-Ps, acts on a post-entry step and impair SARS-CoV-2 replication, potentially by direct degradation of viral RNA. Interestingly, the inhibitory activity of quinoin was conserved also against other members of the Coronaviridae family suggesting a broader antiviral effect. The integration of mass spectrometry (MS)-based proteomics with transcriptomics, provided a comprehensive picture of the quinoin dependent remodeling of crucial biological processes, highlighting an unexpected impact on lipid metabolism. Thus, direct and indirect mechanisms can contribute to the inhibitory mechanism of quinoin, making RIPs family a promising candidate not only for their antiviral activity, but also as an effective tool to better understand the cellular functions and factors required during SARS-CoV-2 replication.
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Affiliation(s)
- Sofia Maria Luigia Tiano
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, Naples, Italy
| | - Nicola Landi
- Institute of Crystallography, National Research Council, Caserta, Italy; Department of Environmental Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy
| | - Valentina Marano
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; PhD Program in Cellular and Molecular Biology, Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Sara Ragucci
- Department of Environmental Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy
| | - Gennaro Bianco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Davide Cacchiarelli
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, Naples, Italy; Department of Translational Medicine, University of Naples "Federico II", Naples, Italy
| | - Paolo Swuec
- Cryo-Electron Microscopy Unit, National Facility for Structural Biology, Human Technopole, Milan, Italy
| | - Malan Silva
- Cryo-Electron Microscopy Unit, National Facility for Structural Biology, Human Technopole, Milan, Italy
| | - Rossella De Cegli
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Francesca Sacco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Antimo Di Maro
- Department of Environmental Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy.
| | - Mirko Cortese
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, Naples, Italy; Department of Environmental Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy.
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2
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Ahmad A, Khan JM, Paray BA, Rashid K, Parvez A. Endolysosomal trapping of therapeutics and endosomal escape strategies. Drug Discov Today 2024; 29:104070. [PMID: 38942071 DOI: 10.1016/j.drudis.2024.104070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 05/31/2024] [Accepted: 06/24/2024] [Indexed: 06/30/2024]
Abstract
Internalizing therapeutic molecules or genes into cells and safely delivering them to the target tissue where they can perform the intended tasks is one of the key characteristics of the smart gene/drug delivery vector. Despite much research in this field, endosomal escape continues to be a significant obstacle to the development of effective gene/drug delivery systems. In this review, we discuss in depth the several types of endocytic pathways involved in the endolysosomal trapping of therapeutic agents. In addition, we describe numerous mechanisms involved in nanoparticle endosomal escape. Furthermore, many other techniques are employed to increase endosomal escape to minimize entrapment of therapeutic compounds within endolysosomes, which have been reviewed at length in this study.
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Affiliation(s)
- Aqeel Ahmad
- Department of Medical Biochemistry, College of Medicine, Shaqra University, Shaqra 11961, Saudi Arabia.
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
| | - Bilal Ahamad Paray
- Department of Zoology, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia
| | - Khalid Rashid
- Department of Urology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ashib Parvez
- Department of Community Medicine, F.H. Medical College, Atal Bihari Vajpayee Medical University, Etmadpur, Agra, India
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3
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Schlaak L, Weise C, Kuropka B, Weng A. Mutational Analysis of RIP Type I Dianthin-30 Suggests a Role for Arg24 in Endocytosis. Toxins (Basel) 2024; 16:219. [PMID: 38787071 PMCID: PMC11125672 DOI: 10.3390/toxins16050219] [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: 01/26/2024] [Revised: 04/30/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
Saponin-mediated endosomal escape is a mechanism that increases the cytotoxicity of type I ribosome-inactivating proteins (type I RIPs). In order to actualize their cytotoxicity, type I RIPs must be released into the cytosol after endocytosis. Without release from the endosomes, type I RIPs are largely degraded and cannot exert their cytotoxic effects. Certain triterpene saponins are able to induce the endosomal escape of these type I RIPs, thus increasing their cytotoxicity. However, the molecular mechanism underlying the endosomal escape enhancement of type I RIPs by triterpene saponins has not been fully elucidated. In this report, we investigate the involvement of the basic amino acid residues of dianthin-30, a type I RIP isolated from the plant Dianthus caryophyllus L., in endosomal escape enhancement using alanine scanning. Therefore, we designed 19 alanine mutants of dianthin-30. Each mutant was combined with SO1861, a triterpene saponin isolated from the roots of Saponaria officinalis L., and subjected to a cytotoxicity screening in Neuro-2A cells. Cytotoxic screening revealed that dianthin-30 mutants with lysine substitutions did not impair the endosomal escape enhancement. There was one particular mutant dianthin, Arg24Ala, that exhibited significantly reduced synergistic cytotoxicity in three mammalian cell lines. However, this reduction was not based on an altered interaction with SO1861. It was, rather, due to the impaired endocytosis of dianthin Arg24Ala into the cells.
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Affiliation(s)
- Louisa Schlaak
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany;
| | - Christoph Weise
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany; (C.W.); (B.K.)
| | - Benno Kuropka
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany; (C.W.); (B.K.)
| | - Alexander Weng
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Str. 2+4, 14195 Berlin, Germany;
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4
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Beltrán JF, Herrera-Belén L, Parraguez-Contreras F, Farías JG, Machuca-Sepúlveda J, Short S. MultiToxPred 1.0: a novel comprehensive tool for predicting 27 classes of protein toxins using an ensemble machine learning approach. BMC Bioinformatics 2024; 25:148. [PMID: 38609877 PMCID: PMC11010298 DOI: 10.1186/s12859-024-05748-z] [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: 08/07/2023] [Accepted: 03/14/2024] [Indexed: 04/14/2024] Open
Abstract
Protein toxins are defense mechanisms and adaptations found in various organisms and microorganisms, and their use in scientific research as therapeutic candidates is gaining relevance due to their effectiveness and specificity against cellular targets. However, discovering these toxins is time-consuming and expensive. In silico tools, particularly those based on machine learning and deep learning, have emerged as valuable resources to address this challenge. Existing tools primarily focus on binary classification, determining whether a protein is a toxin or not, and occasionally identifying specific types of toxins. For the first time, we propose a novel approach capable of classifying protein toxins into 27 distinct categories based on their mode of action within cells. To accomplish this, we assessed multiple machine learning techniques and found that an ensemble model incorporating the Light Gradient Boosting Machine and Quadratic Discriminant Analysis algorithms exhibited the best performance. During the tenfold cross-validation on the training dataset, our model exhibited notable metrics: 0.840 accuracy, 0.827 F1 score, 0.836 precision, 0.840 sensitivity, and 0.989 AUC. In the testing stage, using an independent dataset, the model achieved 0.846 accuracy, 0.838 F1 score, 0.847 precision, 0.849 sensitivity, and 0.991 AUC. These results present a powerful next-generation tool called MultiToxPred 1.0, accessible through a web application. We believe that MultiToxPred 1.0 has the potential to become an indispensable resource for researchers, facilitating the efficient identification of protein toxins. By leveraging this tool, scientists can accelerate their search for these toxins and advance their understanding of their therapeutic potential.
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Affiliation(s)
- Jorge F Beltrán
- Department of Chemical Engineering, Faculty of Engineering and Science, Universidad de La Frontera, Ave. Francisco Salazar, 01145, Temuco, Chile.
| | - Lisandra Herrera-Belén
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomas, Temuco, Chile
| | - Fernanda Parraguez-Contreras
- Department of Chemical Engineering, Faculty of Engineering and Science, Universidad de La Frontera, Ave. Francisco Salazar, 01145, Temuco, Chile
| | - Jorge G Farías
- Department of Chemical Engineering, Faculty of Engineering and Science, Universidad de La Frontera, Ave. Francisco Salazar, 01145, Temuco, Chile
| | - Jorge Machuca-Sepúlveda
- Department of Chemical Engineering, Faculty of Engineering and Science, Universidad de La Frontera, Ave. Francisco Salazar, 01145, Temuco, Chile
| | - Stefania Short
- Department of Chemical Engineering, Faculty of Engineering and Science, Universidad de La Frontera, Ave. Francisco Salazar, 01145, Temuco, Chile
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5
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Zhang G, Fu Y, Li Y, Li Q, Wang S, Shi H. Oral Immunization with Attenuated Salmonella Choleraesuis Expressing the FedF Antigens Protects Mice against the Shiga-Toxin-Producing Escherichia coli Challenge. Biomolecules 2023; 13:1726. [PMID: 38136597 PMCID: PMC10741478 DOI: 10.3390/biom13121726] [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: 10/19/2023] [Revised: 11/18/2023] [Accepted: 11/22/2023] [Indexed: 12/24/2023] Open
Abstract
Edema disease (ED) is a severe and lethal infectious ailment in swine, stemming from Shiga-toxin-producing Escherichia coli (STEC). An efficient, user-friendly, and safe vaccine against ED is urgently required to improve animal welfare and decrease antibiotic consumption. Recombinant attenuated Salmonella vaccines (RASV) administered orally induce both humoral and mucosal immune responses to the immunizing antigen. Their potential for inducing protective immunity against ED is significant through the delivery of STEC antigens. rSC0016 represents an enhanced recombinant attenuated vaccine vector designed for Salmonella enterica serotype Choleraesuis. It combines sopB mutations with a regulated delay system to strike a well-balanced equilibrium between host safety and immunogenicity. We generated recombinant vaccine strains, namely rSC0016 (pS-FedF) and rSC0016 (pS-rStx2eA), and assessed their safety and immunogenicity in vivo. The findings demonstrated that the mouse models immunized with rSC0016 (pS-FedF) and rSC0016 (pS-rStx2eA) generated substantial IgG antibody responses to FedF and rStx2eA, while also provoking robust mucosal and cellular immune responses against both FedF and rStx2eA. The protective impact of rSC0016 (pS-FedF) against Shiga-toxin-producing Escherichia coli surpassed that of rSC0016 (pS-rStx2eA), with percentages of 83.3%. These findings underscore that FedF has greater suitability for vaccine delivery via recombinant attenuated Salmonella vaccines (RASVs). Overall, this study provides a promising candidate vaccine for infection with STEC.
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Affiliation(s)
- Guihua Zhang
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China; (G.Z.); (Y.F.); (Q.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Yang Fu
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China; (G.Z.); (Y.F.); (Q.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Yu’an Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China; (G.Z.); (Y.F.); (Q.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Quan Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China; (G.Z.); (Y.F.); (Q.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Shifeng Wang
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611-0880, USA;
| | - Huoying Shi
- College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China; (G.Z.); (Y.F.); (Q.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University (JIRLAAPS), Yangzhou 225009, China
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6
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Guyette JL, Serrano A, Huhn III GR, Taylor M, Malkòm P, Curtis D, Teter K. Reduction is sufficient for the disassembly of ricin and Shiga toxin 1 but not Escherichia coli heat-labile enterotoxin. Infect Immun 2023; 91:e0033223. [PMID: 37877711 PMCID: PMC10652930 DOI: 10.1128/iai.00332-23] [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: 08/21/2023] [Accepted: 09/21/2023] [Indexed: 10/26/2023] Open
Abstract
Many AB toxins contain an enzymatic A moiety that is anchored to a cell-binding B moiety by a disulfide bridge. After receptor-mediated endocytosis, some AB toxins undergo retrograde transport to the endoplasmic reticulum (ER) where reduction of the disulfide bond occurs. The reduced A subunit then dissociates from the holotoxin and enters the cytosol to alter its cellular target. Intoxication requires A chain separation from the holotoxin, but, for many toxins, it is unclear if reduction alone is sufficient for toxin disassembly. Here, we examined the link between reduction and disassembly for several ER-translocating toxins. We found disassembly of the reduced Escherichia coli heat-labile enterotoxin (Ltx) required an interaction with one specific ER-localized oxidoreductase: protein disulfide isomerase (PDI). In contrast, the reduction and disassembly of ricin toxin (Rtx) and Shiga toxin 1 (Stx1) were coupled events that did not require PDI and could be triggered by reductant alone. PDI-deficient cells accordingly exhibited high resistance to Ltx with continued sensitivity to Rtx and Stx1. The distinct structural organization of each AB toxin thus appears to determine whether holotoxin disassembly occurs spontaneously upon disulfide reduction or requires the additional input of PDI.
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Affiliation(s)
- Jessica L. Guyette
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Albert Serrano
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - G. Robb Huhn III
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Michael Taylor
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Pat Malkòm
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - David Curtis
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
| | - Ken Teter
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, Florida, USA
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7
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Buser DP, Spang A. Protein sorting from endosomes to the TGN. Front Cell Dev Biol 2023; 11:1140605. [PMID: 36895788 PMCID: PMC9988951 DOI: 10.3389/fcell.2023.1140605] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/09/2023] [Indexed: 02/23/2023] Open
Abstract
Retrograde transport from endosomes to the trans-Golgi network is essential for recycling of protein and lipid cargoes to counterbalance anterograde membrane traffic. Protein cargo subjected to retrograde traffic include lysosomal acid-hydrolase receptors, SNARE proteins, processing enzymes, nutrient transporters, a variety of other transmembrane proteins, and some extracellular non-host proteins such as viral, plant, and bacterial toxins. Efficient delivery of these protein cargo molecules depends on sorting machineries selectively recognizing and concentrating them for their directed retrograde transport from endosomal compartments. In this review, we outline the different retrograde transport pathways governed by various sorting machineries involved in endosome-to-TGN transport. In addition, we discuss how this transport route can be analyzed experimentally.
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Affiliation(s)
| | - Anne Spang
- *Correspondence: Dominik P. Buser, ; Anne Spang,
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8
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Distinct changes in endosomal composition promote NLRP3 inflammasome activation. Nat Immunol 2023; 24:30-41. [PMID: 36443515 PMCID: PMC9810532 DOI: 10.1038/s41590-022-01355-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 10/06/2022] [Indexed: 11/30/2022]
Abstract
Inflammasome complexes are pivotal in the innate immune response. The NLR family pyrin domain containing protein 3 (NLRP3) inflammasome is activated in response to a broad variety of cellular stressors. However, a primary and converging sensing mechanism by the NLRP3 receptor initiating inflammasome assembly remains ill defined. Here, we demonstrate that NLRP3 inflammasome activators primarily converge on disruption of endoplasmic reticulum-endosome membrane contact sites (EECS). This defect causes endosomal accumulation of phosphatidylinositol 4-phosphate (PI4P) and a consequent impairment of endosome-to-trans-Golgi network trafficking (ETT), necessary steps for endosomal recruitment of NLRP3 and subsequent inflammasome activation. Lowering endosomal PI4P levels prevents endosomal association of NLRP3 and inhibits inflammasome activation. Disruption of EECS or ETT is sufficient to enhance endosomal PI4P levels, to recruit NLRP3 to endosomes and to potentiate NLRP3 inflammasome activation. Mice with defects in ETT in the myeloid compartment are more susceptible to lipopolysaccharide-induced sepsis. Our study thus identifies a distinct cellular mechanism leading to endosomal NLRP3 recruitment and inflammasome activation.
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9
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Clinton M, Król E, Sepúlveda D, Andersen NR, Brierley AS, Ferrier DEK, Hansen PJ, Lorenzen N, Martin SAM. Gill Transcriptomic Responses to Toxin-producing Alga Prymnesium parvum in Rainbow Trout. Front Immunol 2021; 12:794593. [PMID: 34956228 PMCID: PMC8693183 DOI: 10.3389/fimmu.2021.794593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 11/19/2021] [Indexed: 11/24/2022] Open
Abstract
The gill of teleost fish is a multifunctional organ involved in many physiological processes, including protection of the mucosal gill surface against pathogens and other environmental antigens by the gill-associated lymphoid tissue (GIALT). Climate change associated phenomena, such as increasing frequency and magnitude of harmful algal blooms (HABs) put extra strain on gill function, contributing to enhanced fish mortality and fish kills. However, the molecular basis of the HAB-induced gill injury remains largely unknown due to the lack of high-throughput transcriptomic studies performed on teleost fish in laboratory conditions. We used juvenile rainbow trout (Oncorhynchus mykiss) to investigate the transcriptomic responses of the gill tissue to two (high and low) sublethal densities of the toxin-producing alga Prymnesium parvum, in relation to non-exposed control fish. The exposure time to P. parvum (4–5 h) was sufficient to identify three different phenotypic responses among the exposed fish, enabling us to focus on the common gill transcriptomic responses to P. parvum that were independent of dose and phenotype. The inspection of common differentially expressed genes (DEGs), canonical pathways, upstream regulators and downstream effects pointed towards P. parvum-induced inflammatory response and gill inflammation driven by alterations of Acute Phase Response Signalling, IL-6 Signalling, IL-10 Signalling, Role of PKR in Interferon Induction and Antiviral Response, IL-8 Signalling and IL-17 Signalling pathways. While we could not determine if the inferred gill inflammation was progressing or resolving, our study clearly suggests that P. parvum blooms may contribute to the serious gill disorders in fish. By providing insights into the gill transcriptomic responses to toxin-producing P. parvum in teleost fish, our research opens new avenues for investigating how to monitor and mitigate toxicity of HABs before they become lethal.
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Affiliation(s)
- Morag Clinton
- School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom.,Scottish Oceans Institute, University of St Andrews, St Andrews, United Kingdom.,Department of Veterinary Medicine, University of Alaska Fairbanks, Fairbanks, AK, United States
| | - Elżbieta Król
- School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Dagoberto Sepúlveda
- National Institute of Aquatic Resources, Technical University of Denmark, Kgs. Lyngby, Denmark
| | | | - Andrew S Brierley
- Scottish Oceans Institute, University of St Andrews, St Andrews, United Kingdom
| | - David E K Ferrier
- Scottish Oceans Institute, University of St Andrews, St Andrews, United Kingdom
| | - Per Juel Hansen
- Department of Biology, Marine Biological Section, University of Copenhagen, Helsingør, Denmark
| | - Niels Lorenzen
- National Institute of Aquatic Resources, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Samuel A M Martin
- School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom
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10
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Ramasamy K, Balasubramanian S, Kirkpatrick A, Szabo D, Pandranki L, Baseman JB, Kannan TR. Mycoplasma pneumoniae CARDS toxin exploits host cell endosomal acidic pH and vacuolar ATPase proton pump to execute its biological activities. Sci Rep 2021; 11:11571. [PMID: 34078958 PMCID: PMC8172646 DOI: 10.1038/s41598-021-90948-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 05/19/2021] [Indexed: 11/09/2022] Open
Abstract
Mycoplasma pneumoniae is the leading cause of bacterial community-acquired pneumonia among hospitalized children in the United States. It is also responsible for a spectrum of other respiratory tract disorders and extrapulmonary manifestations in children and adults. The main virulence factor of M. pneumoniae is a 591 amino acid multifunctional protein called Community Acquired Respiratory Distress Syndrome (CARDS) toxin. The amino terminal region of CARDS toxin (N-CARDS) retains ADP-ribosylating activity and the carboxy region (C-CARDS) contains the receptor binding and vacuolating activities. After internalization, CARDS toxin is transported in a retrograde manner from endosome through the Golgi complex into the endoplasmic reticulum. However, the mechanisms and criteria by which internalized CARDS toxin is transported and activated to execute its cytotoxic effects remain unknown. In this study, we used full-length CARDS toxin and its mutant and truncated derivatives to analyze how pharmacological drugs that alter pH of intracellular vesicles and electrical potential across vesicular membranes affect translocation of CARDS toxin in mammalian cells. Our results indicate that an acidic environment is essential for CARDS toxin retrograde transport to endoplasmic reticulum. Moreover, retrograde transport facilitates toxin clipping and is required to induce vacuole formation. Additionally, toxin-mediated cell vacuolation is strictly dependent on the function of vacuolar type-ATPase.
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Affiliation(s)
- Kumaraguruparan Ramasamy
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Sowmya Balasubramanian
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Alejandra Kirkpatrick
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Daniel Szabo
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Lavanya Pandranki
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - Joel B Baseman
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA
| | - T R Kannan
- Department of Microbiology, Immunology and Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, 78229, USA.
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11
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The Protein Toxins Ricin and Shiga Toxin as Tools to Explore Cellular Mechanisms of Internalization and Intracellular Transport. Toxins (Basel) 2021; 13:toxins13060377. [PMID: 34070659 PMCID: PMC8227415 DOI: 10.3390/toxins13060377] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/12/2021] [Accepted: 05/22/2021] [Indexed: 12/18/2022] Open
Abstract
Protein toxins secreted by bacteria and found in plants can be threats to human health. However, their extreme toxicity can also be exploited in different ways, e.g., to produce hybrid toxins directed against cancer cells and to study transport mechanisms in cells. Investigations during the last decades have shown how powerful these molecules are as tools in cell biological research. Here, we first present a partly historical overview, with emphasis on Shiga toxin and ricin, of how such toxins have been used to characterize processes and proteins of importance for their trafficking. In the second half of the article, we describe how one can now use toxins to investigate the role of lipid classes for intracellular transport. In recent years, it has become possible to quantify hundreds of lipid species using mass spectrometry analysis. Thus, it is also now possible to explore the importance of lipid species in intracellular transport. The detailed analyses of changes in lipids seen under conditions of inhibited toxin transport reveal previously unknown connections between syntheses of lipid classes and demonstrate the ability of cells to compensate under given conditions.
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12
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Rádis-Baptista G. Cell-Penetrating Peptides Derived from Animal Venoms and Toxins. Toxins (Basel) 2021; 13:147. [PMID: 33671927 PMCID: PMC7919042 DOI: 10.3390/toxins13020147] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/31/2021] [Accepted: 02/09/2021] [Indexed: 12/18/2022] Open
Abstract
Cell-penetrating peptides (CPPs) comprise a class of short polypeptides that possess the ability to selectively interact with the cytoplasmic membrane of certain cell types, translocate across plasma membranes and accumulate in the cell cytoplasm, organelles (e.g., the nucleus and mitochondria) and other subcellular compartments. CPPs are either of natural origin or de novo designed and synthesized from segments and patches of larger proteins or designed by algorithms. With such intrinsic properties, along with membrane permeation, translocation and cellular uptake properties, CPPs can intracellularly convey diverse substances and nanomaterials, such as hydrophilic organic compounds and drugs, macromolecules (nucleic acids and proteins), nanoparticles (nanocrystals and polyplexes), metals and radionuclides, which can be covalently attached via CPP N- and C-terminals or through preparation of CPP complexes. A cumulative number of studies on animal toxins, primarily isolated from the venom of arthropods and snakes, have revealed the cell-penetrating activities of venom peptides and toxins, which can be harnessed for application in biomedicine and pharmaceutical biotechnology. In this review, I aimed to collate examples of peptides from animal venoms and toxic secretions that possess the ability to penetrate diverse types of cells. These venom CPPs have been chemically or structurally modified to enhance cell selectivity, bioavailability and a range of target applications. Herein, examples are listed and discussed, including cysteine-stabilized and linear, α-helical peptides, with cationic and amphipathic character, from the venom of insects (e.g., melittin, anoplin, mastoparans), arachnids (latarcin, lycosin, chlorotoxin, maurocalcine/imperatoxin homologs and wasabi receptor toxin), fish (pardaxins), amphibian (bombesin) and snakes (crotamine and cathelicidins).
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Affiliation(s)
- Gandhi Rádis-Baptista
- Laboratory of Biochemistry and Biotechnology, Institute for Marine Sciences, Federal University of Ceara, Fortaleza 60165-081, Brazil
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13
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Acosta W, Cramer CL. Targeting Macromolecules to CNS and Other Hard-to-Treat Organs Using Lectin-Mediated Delivery. Int J Mol Sci 2020; 21:ijms21030971. [PMID: 32024082 PMCID: PMC7037663 DOI: 10.3390/ijms21030971] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 02/07/2023] Open
Abstract
The greatest challenges for therapeutic efficacy of many macromolecular drugs that act on intracellular are delivery to key organs and tissues and delivery into cells and subcellular compartments. Transport of drugs into critical cells associated with disease, including those in organs protected by restrictive biological barriers such as central nervous system (CNS), bone, and eye remains a significant hurdle to drug efficacy and impacts commercial risk and incentives for drug development for many diseases. These limitations expose a significant need for the development of novel strategies for macromolecule delivery. RTB lectin is the non-toxic carbohydrate-binding subunit B of ricin toxin with high affinity for galactose/galactosamine-containing glycolipids and glycoproteins common on human cell surfaces. RTB mediates endocytic uptake into mammalian cells by multiple routes exploiting both adsorptive-mediated and receptor-mediated mechanisms. In vivo biodistribution studies in lysosomal storage disease models provide evidence for the theory that the RTB-lectin transports corrective doses of enzymes across the blood–brain barrier to treat CNS pathologies. These results encompass significant implications for protein-based therapeutic approaches to address lysosomal and other diseases having strong CNS involvement.
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14
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Berdasco C, Duhalde Vega M, Rosato-Siri MV, Goldstein J. Environmental Cues Modulate Microglial Cell Behavior Upon Shiga Toxin 2 From Enterohemorrhagic Escherichia coli Exposure. Front Cell Infect Microbiol 2020; 9:442. [PMID: 31970091 PMCID: PMC6960108 DOI: 10.3389/fcimb.2019.00442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/09/2019] [Indexed: 12/18/2022] Open
Abstract
Shiga toxin (Stx) produced by enterohemorrhagic E. coli produces hemolytic uremic syndrome and encephalopathies in patients, which can lead to either reversible or permanent neurological abnormalities, or even fatal cases depending on the degree of intoxication. It has been observed that the inflammatory component plays a decisive role in the severity of the disease. Therefore, the objective of this work was to evaluate the behavior of microglial cell primary cultures upon Stx2 exposure and heat shock or lipopolysaccharide challenges, as cues which modulate cellular environments, mimicking fever and inflammation states, respectively. In these contexts, activated microglial cells incorporated Stx2, increased their metabolism, phagocytic capacity, and pro-inflammatory profile. Stx2 uptake was associated to receptor globotriaosylceramide (Gb3)-pathway. Gb3 had three clearly distinguishable distribution patterns which varied according to different contexts. In addition, toxin uptake exhibited both a Gb3-dependent and a Gb3-independent binding depending on those contexts. Altogether, these results suggest a fundamental role for microglial cells in pro-inflammatory processes in encephalopathies due to Stx2 intoxication and highlight the impact of environmental cues.
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Affiliation(s)
- Clara Berdasco
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maite Duhalde Vega
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - María Victoria Rosato-Siri
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - Jorge Goldstein
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
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15
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The C. difficile toxin B membrane translocation machinery is an evolutionarily conserved protein delivery apparatus. Nat Commun 2020; 11:432. [PMID: 31974369 PMCID: PMC6978384 DOI: 10.1038/s41467-020-14306-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022] Open
Abstract
Large Clostridial Toxins (LCTs) are a family of six homologous protein toxins that are implicated in severe disease. LCTs infiltrate host cells using a translocation domain (LCT-T) that contains both cell-surface receptor binding sites and a membrane translocation apparatus. Despite much effort, LCT translocation remains poorly understood. Here we report the identification of 1104 LCT-T homologs, with 769 proteins from bacteria outside of clostridia. Sequences are widely distributed in pathogenic and host-associated species, in a variety of contexts and architectures. Consistent with these homologs being functional toxins, we show that a distant LCT-T homolog from Serratia marcescens acts as a pH-dependent translocase to deliver its effector into host cells. Based on evolutionary footprinting of LCT-T homologs, we further define an evolutionarily conserved translocase region that we show is an autonomous translocase capable of delivering heterologous cargo into host cells. Our work uncovers a broad class of translocating toxins and provides insights into LCT translocation. Large Clostridial toxins infiltrate host cells using a translocation domain (LCT-T). Here, using a genomics-driven approach and functional assays, the authors uncover the presence of distant LCT-T homologs in bacteria outside clostridia and provide evidence for a toxic effector function in the gammaproteobacterium Serratia marcescens.
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16
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Hämälistö S, Stahl JL, Favaro E, Yang Q, Liu B, Christoffersen L, Loos B, Guasch Boldú C, Joyce JA, Reinheckel T, Barisic M, Jäättelä M. Spatially and temporally defined lysosomal leakage facilitates mitotic chromosome segregation. Nat Commun 2020; 11:229. [PMID: 31932607 PMCID: PMC6957743 DOI: 10.1038/s41467-019-14009-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 12/11/2019] [Indexed: 12/12/2022] Open
Abstract
Lysosomes are membrane-surrounded cytoplasmic organelles filled with a powerful cocktail of hydrolases. Besides degrading cellular constituents inside the lysosomal lumen, lysosomal hydrolases promote tissue remodeling when delivered to the extracellular space and cell death when released to the cytosol. Here, we show that spatially and temporally controlled lysosomal leakage contributes to the accurate chromosome segregation in normal mammalian cell division. One or more chromatin-proximal lysosomes leak in the majority of prometaphases, after which active cathepsin B (CTSB) localizes to the metaphase chromatin and cleaves a small subset of histone H3. Stabilization of lysosomal membranes or inhibition of CTSB activity during mitotic entry results in a significant increase in telomere-related chromosome segregation defects, whereas cells and tissues lacking CTSB and cells expressing CTSB-resistant histone H3 accumulate micronuclei and other nuclear defects. These data suggest that lysosomal leakage and chromatin-associated CTSB contribute to proper chromosome segregation and maintenance of genomic integrity. Lysosomes are intracellular organelles containing degradative enzymes, and leakage of lysosomal contents into the cell is thought to trigger cell death. Here, the authors report that leaky lysosomes may facilitate chromosome separation during cell division.
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Affiliation(s)
- Saara Hämälistö
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Jonathan Lucien Stahl
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Elena Favaro
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Qing Yang
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Bin Liu
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Line Christoffersen
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Ben Loos
- Department of Physiological Sciences, Stellenbosch University, 7600, Stellenbosch, South Africa
| | - Claudia Guasch Boldú
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark
| | - Johanna A Joyce
- Ludwig Institute for Cancer Research, University of Lausanne, 1005, Lausanne, Switzerland
| | - Thomas Reinheckel
- Institute of Molecular Medicine and Cell Research, Medical Faculty, University of Freiburg, 79104, Freiburg, Germany.,German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, partner site Freiburg, 79106, Freiburg, Germany
| | - Marin Barisic
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark.,Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Marja Jäättelä
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, 2100, Copenhagen, Denmark. .,Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
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17
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Sun C, Dong M, Song Y, Zhang J, Wang Y, Chang Y, Yu H, Xu N, Xie Z, Liu W. Enhancing the antivirus activity of chimeric canine interferon with ricin subunit B by using nanoparticle formulations. RSC Adv 2020; 10:12671-12679. [PMID: 35497620 PMCID: PMC9051121 DOI: 10.1039/c9ra10557c] [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] [Received: 12/15/2019] [Accepted: 02/18/2020] [Indexed: 12/04/2022] Open
Abstract
Despite interferon alpha having a broad spectrum of antiviral activity and strong antiproliferative activity, its applications are severely limited due to the intrinsic properties of proteins, such as poor stability and short serum half-life. In our study, canine interferon alpha (CaIFNα) gene was fused with the ricin toxin B chain (RTB) to form rCaIFNα/RTB, which encodes a 463-amino acid protein containing a 15-amino acid encoded (G4S)3 flexible linker. After expression in prokaryote, purification and renaturation, the cytotoxicity and antiviral activity of rCaIFNα/RTB were investigated in Madin–Darby canine kidney (MDCK) cells. rCaIFNα/RTB exerted a superior anti-vesicular stomatitis virus (VSV) activity on MDCK cells. Furthermore, we have developed a nanoparticle formulation of rCaIFNα/RTB by using polyethylenimine (PEI) through electrostatic interaction. rCaIFNα/RTB@PEI10000 is more stable than rCaIFNα/RTB at various pH and temperature levels, and it possesses enhanced antiviral activity. Our findings facilitate further research on the role of type I IFN in antiviral defense responses in Canis lupus familiaris. Despite interferon alpha having a broad spectrum of antiviral activity and strong antiproliferative activity, its applications are severely limited due to the intrinsic properties of proteins, such as poor stability and short serum half-life.![]()
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Affiliation(s)
- Chengbiao Sun
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
| | - Mingxin Dong
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
| | - Yucong Song
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- China Academy of Sciences
- Changchun
- P. R. China
| | - Jianxu Zhang
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
| | - Yan Wang
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
| | | | - Haotian Yu
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
| | - Na Xu
- Jilin Medical University
- P. R. China
| | - Zhigang Xie
- State Key Laboratory of Polymer Physics and Chemistry
- Changchun Institute of Applied Chemistry
- China Academy of Sciences
- Changchun
- P. R. China
| | - Wensen Liu
- Institute of Military Veterinary Medicine
- Academy of Military Medical Sciences
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control
- Changchun
- P. R. China
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18
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Francia V, Montizaan D, Salvati A. Interactions at the cell membrane and pathways of internalization of nano-sized materials for nanomedicine. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2020; 11:338-353. [PMID: 32117671 PMCID: PMC7034226 DOI: 10.3762/bjnano.11.25] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/27/2020] [Indexed: 05/17/2023]
Abstract
Nano-sized materials have great potential as drug carriers for nanomedicine applications. Thanks to their size, they can exploit the cellular machinery to enter cells and be trafficked intracellularly, thus they can be used to overcome some of the cellular barriers to drug delivery. Nano-sized drug carriers of very different properties can be prepared, and their surface can be modified by the addition of targeting moieties to recognize specific cells. However, it is still difficult to understand how the material properties affect the subsequent interactions and outcomes at cellular level. As a consequence of this, designing targeted drugs remains a major challenge in drug delivery. Within this context, we discuss the current understanding of the initial steps in the interactions of nano-sized materials with cells in relation to nanomedicine applications. In particular, we focus on the difficult interplay between the initial adhesion of nano-sized materials to the cell surface, the potential recognition by cell receptors, and the subsequent mechanisms cells use to internalize them. The factors affecting these initial events are discussed. Then, we briefly describe the different pathways of endocytosis in cells and illustrate with some examples the challenges in understanding how nanomaterial properties, such as size, charge, and shape, affect the mechanisms cells use for their internalization. Technical difficulties in characterizing these mechanisms are presented. A better understanding of the first interactions of nano-sized materials with cells will help to design nanomedicines with improved targeting.
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Affiliation(s)
- Valentina Francia
- Groningen Research Institute of Pharmacy, University of Groningen, 9713AV Groningen, Netherlands
| | - Daphne Montizaan
- Groningen Research Institute of Pharmacy, University of Groningen, 9713AV Groningen, Netherlands
| | - Anna Salvati
- Groningen Research Institute of Pharmacy, University of Groningen, 9713AV Groningen, Netherlands
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19
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Morgens DW, Chan C, Kane AJ, Weir NR, Li A, Dubreuil MM, Tsui CK, Hess GT, Lavertu A, Han K, Polyakov N, Zhou J, Handy EL, Alabi P, Dombroski A, Yao D, Altman RB, Sello JK, Denic V, Bassik MC. Retro-2 protects cells from ricin toxicity by inhibiting ASNA1-mediated ER targeting and insertion of tail-anchored proteins. eLife 2019; 8:48434. [PMID: 31674906 PMCID: PMC6858068 DOI: 10.7554/elife.48434] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/28/2019] [Indexed: 12/11/2022] Open
Abstract
The small molecule Retro-2 prevents ricin toxicity through a poorly-defined mechanism of action (MOA), which involves halting retrograde vesicle transport to the endoplasmic reticulum (ER). CRISPRi genetic interaction analysis revealed Retro-2 activity resembles disruption of the transmembrane domain recognition complex (TRC) pathway, which mediates post-translational ER-targeting and insertion of tail-anchored (TA) proteins, including SNAREs required for retrograde transport. Cell-based and in vitro assays show that Retro-2 blocks delivery of newly-synthesized TA-proteins to the ER-targeting factor ASNA1 (TRC40). An ASNA1 point mutant identified using CRISPR-mediated mutagenesis abolishes both the cytoprotective effect of Retro-2 against ricin and its inhibitory effect on ASNA1-mediated ER-targeting. Together, our work explains how Retro-2 prevents retrograde trafficking of toxins by inhibiting TA-protein targeting, describes a general CRISPR strategy for predicting the MOA of small molecules, and paves the way for drugging the TRC pathway to treat broad classes of viruses known to be inhibited by Retro-2.
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Affiliation(s)
- David W Morgens
- Department of Genetics, Stanford University, Stanford, United States
| | - Charlene Chan
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Andrew J Kane
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Nicholas R Weir
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Amy Li
- Department of Genetics, Stanford University, Stanford, United States
| | | | - C Kimberly Tsui
- Department of Genetics, Stanford University, Stanford, United States
| | - Gaelen T Hess
- Department of Genetics, Stanford University, Stanford, United States
| | - Adam Lavertu
- Biomedical Informatics Training Program, Stanford University, Stanford, United States
| | - Kyuho Han
- Department of Genetics, Stanford University, Stanford, United States
| | - Nicole Polyakov
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Jing Zhou
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Emma L Handy
- Department of Chemistry, Brown University, Providence, United States
| | - Philip Alabi
- Department of Chemistry, Brown University, Providence, United States
| | - Amanda Dombroski
- Department of Chemistry, Brown University, Providence, United States
| | - David Yao
- Department of Genetics, Stanford University, Stanford, United States
| | - Russ B Altman
- Department of Genetics, Stanford University, Stanford, United States.,Bioengineering, Stanford University, Stanford, United States
| | - Jason K Sello
- Department of Chemistry, Brown University, Providence, United States
| | - Vladimir Denic
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Michael C Bassik
- Department of Genetics, Stanford University, Stanford, United States.,Program in Cancer Biology, Stanford University, Stanford, United States.,Stanford University Chemistry, Engineering, and Medicine for Human Health (ChEM-H), Stanford, United States
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20
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Critical Issues in the Development of Immunotoxins for Anticancer Therapy. J Pharm Sci 2019; 109:104-115. [PMID: 31669121 DOI: 10.1016/j.xphs.2019.10.037] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/23/2019] [Accepted: 10/21/2019] [Indexed: 12/16/2022]
Abstract
Immunotoxins (ITs) are attractive anticancer modalities aimed at cancer-specific delivery of highly potent cytotoxic protein toxins. An IT consists of a targeting domain (an antibody, cytokine, or another cell-binding protein) chemically conjugated or recombinantly fused to a highly cytotoxic payload (a bacterial and plant toxin or human cytotoxic protein). The mode of action of ITs is killing designated cancer cells through the effector function of toxins in the cytosol after cellular internalization via the targeted cell-specific receptor-mediated endocytosis. Although numerous ITs of diverse structures have been tested in the past decades, only 3 ITs-denileukin diftitox, tagraxofusp, and moxetumomab pasudotox-have been clinically approved for treating hematological cancers. No ITs against solid tumors have been approved for clinical use. In this review, we discuss critical research and development issues associated with ITs that limit their clinical success as well as strategies to overcome these obstacles. The issues include off-target and on-target toxicities, immunogenicity, human cytotoxic proteins, antigen target selection, cytosolic delivery efficacy, solid-tumor targeting, and developability. To realize the therapeutic promise of ITs, novel strategies for safe and effective cytosolic delivery into designated tumors, including solid tumors, are urgently needed.
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21
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Intracellular Transport and Cytotoxicity of the Protein Toxin Ricin. Toxins (Basel) 2019; 11:toxins11060350. [PMID: 31216687 PMCID: PMC6628406 DOI: 10.3390/toxins11060350] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/17/2022] Open
Abstract
Ricin can be isolated from the seeds of the castor bean plant (Ricinus communis). It belongs to the ribosome-inactivating protein (RIP) family of toxins classified as a bio-threat agent due to its high toxicity, stability and availability. Ricin is a typical A-B toxin consisting of a single enzymatic A subunit (RTA) and a binding B subunit (RTB) joined by a single disulfide bond. RTA possesses an RNA N-glycosidase activity; it cleaves ribosomal RNA leading to the inhibition of protein synthesis. However, the mechanism of ricin-mediated cell death is quite complex, as a growing number of studies demonstrate that the inhibition of protein synthesis is not always correlated with long term ricin toxicity. To exert its cytotoxic effect, ricin A-chain has to be transported to the cytosol of the host cell. This translocation is preceded by endocytic uptake of the toxin and retrograde traffic through the trans-Golgi network (TGN) and the endoplasmic reticulum (ER). In this article, we describe intracellular trafficking of ricin with particular emphasis on host cell factors that facilitate this transport and contribute to ricin cytotoxicity in mammalian and yeast cells. The current understanding of the mechanisms of ricin-mediated cell death is discussed as well. We also comment on recent reports presenting medical applications for ricin and progress associated with the development of vaccines against this toxin.
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22
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Deprey K, Becker L, Kritzer J, Plückthun A. Trapped! A Critical Evaluation of Methods for Measuring Total Cellular Uptake versus Cytosolic Localization. Bioconjug Chem 2019; 30:1006-1027. [PMID: 30882208 PMCID: PMC6527423 DOI: 10.1021/acs.bioconjchem.9b00112] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Biomolecules have many properties that make them promising for intracellular therapeutic applications, but delivery remains a key challenge because large biomolecules cannot easily enter the cytosol. Furthermore, quantification of total intracellular versus cytosolic concentrations remains demanding, and the determination of delivery efficiency is thus not straightforward. In this review, we discuss strategies for delivering biomolecules into the cytosol and briefly summarize the mechanisms of uptake for these systems. We then describe commonly used methods to measure total cellular uptake and, more selectively, cytosolic localization, and discuss the major advantages and drawbacks of each method. We critically evaluate methods of measuring "cell penetration" that do not adequately distinguish total cellular uptake and cytosolic localization, which often lead to inaccurate interpretations of a molecule's cytosolic localization. Finally, we summarize the properties and components of each method, including the main caveats of each, to allow for informed decisions about method selection for specific applications. When applied correctly and interpreted carefully, methods for quantifying cytosolic localization offer valuable insight into the bioactivity of biomolecules and potentially the prospects for their eventual development into therapeutics.
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Affiliation(s)
- Kirsten Deprey
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155, United States
| | - Lukas Becker
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Joshua Kritzer
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155, United States
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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23
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Brigotti M, Orth-Höller D, Carnicelli D, Porcellini E, Galassi E, Tazzari PL, Ricci F, Manoli F, Manet I, Talasz H, Lindner HH, Speth C, Erbeznik T, Fuchs S, Posch W, Chatterjee S, Würzner R. The structure of the Shiga toxin 2a A-subunit dictates the interactions of the toxin with blood components. Cell Microbiol 2019; 21:e13000. [PMID: 30578712 PMCID: PMC6492301 DOI: 10.1111/cmi.13000] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 12/06/2018] [Accepted: 12/17/2018] [Indexed: 12/29/2022]
Abstract
Hemolytic uremic syndrome (eHUS) is a severe complication of human infections with Shiga toxins (Stxs)-producing Escherichia coli. A key step in the pathogenesis of eHUS is the interaction of Stxs with blood components before the targeting of renal endothelial cells. Here, we show that a single proteolytic cleavage in the Stx2a A-subunit, resulting into two fragments (A1 and A2) linked by a disulfide bridge (cleaved Stx2a), dictates different binding abilities. Uncleaved Stx2a was confirmed to bind to human neutrophils and to trigger leukocyte/platelet aggregate formation, whereas cleaved Stx2a was ineffective. Conversely, binding of complement factor H was confirmed for cleaved Stx2a and not for uncleaved Stx2a. It is worth noting that uncleaved and cleaved Stx2a showed no differences in cytotoxicity for Vero cells or Raji cells, structural conformation, and contaminating endotoxin. These results have been obtained by comparing two Stx2a batches, purified in different laboratories by using different protocols, termed Stx2a(cl; cleaved toxin, Innsbruck) and Stx2a(uncl; uncleaved toxin, Bologna). Stx2a(uncl) behaved as Stx2a(cl) after mild trypsin treatment. In this light, previous controversial results obtained with purified Stx2a has to be critically re-evaluated; furthermore, characterisation of the structure of circulating Stx2a is mandatory to understand eHUS-pathogenesis and to develop therapeutic approaches.
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Affiliation(s)
- Maurizio Brigotti
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale, Sede di Patologia Generale, Università di Bologna, Bologna, Italy
| | - Dorothea Orth-Höller
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Domenica Carnicelli
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale, Sede di Patologia Generale, Università di Bologna, Bologna, Italy
| | - Elisa Porcellini
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale, Sede di Patologia Generale, Università di Bologna, Bologna, Italy
| | - Elisabetta Galassi
- Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale, Sede di Patologia Generale, Università di Bologna, Bologna, Italy
| | - Pier Luigi Tazzari
- Servizio di Immunoematologia e Trasfusionale, Ospedale S. Orsola-Malpighi, Bologna, Italy
| | - Francesca Ricci
- Servizio di Immunoematologia e Trasfusionale, Ospedale S. Orsola-Malpighi, Bologna, Italy
| | - Francesco Manoli
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, Bologna, Italy
| | - Ilse Manet
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, Bologna, Italy
| | - Heribert Talasz
- Division of Clinical Biochemistry, Biocentre, Medical University of Innsbruck, Innsbruck, Austria
| | - Herbert H Lindner
- Division of Clinical Biochemistry, Biocentre, Medical University of Innsbruck, Innsbruck, Austria
| | - Cornelia Speth
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Thomas Erbeznik
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Stefan Fuchs
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Wilfried Posch
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Sneha Chatterjee
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Reinhard Würzner
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
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24
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Fornaguera C, Castells-Sala C, Borrós S. Unraveling Polymeric Nanoparticles Cell Uptake Pathways: Two Decades Working to Understand Nanoparticles Journey to Improve Gene Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1288:117-138. [PMID: 31916235 DOI: 10.1007/5584_2019_467] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Polymeric nanoparticles have aroused an increasing interest in the last decades as novel advanced delivery systems to improve the treatment of many diseases. Hard work has been performed worldwide designing and developing polymeric nanoparticles using different building blocks, which target specific cell types, trying to avoid bioaccumulation and degradation pathways. The main handicap of the design is to understand the final fate and the journey that the nanoparticle will follow, which is intimately ligated with the chemical and physical properties of the nanoparticles themselves and specific factors of the targeted cells. Although the huge number of published scientific articles regarding polymeric nanoparticles for biomedical applications, their use in clinics is still limited. This fact could be explained by the limited data reporting the interaction of the huge diversity of polymeric nanoparticles with cells. This knowledge is essential to understand nanoparticle uptake and trafficking inside cells to the subcellular target structure.In this chapter, we aim to contribute to this field of knowledge by: (1) summarizing the polymeric nanoparticles properties and cellular factors that influence nanoparticle endocytosis and (2) reviewing the endocytic pathways classified as a function of nanoparticle size and as a function of the receptor playing a role. The revision of previously reported endocytic pathways for particular polymeric nanoparticles could facilitate scientist involved in this field to easily delineate efficient delivery systems based on polymeric nanoparticles.
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Affiliation(s)
- C Fornaguera
- Grup d'Enginyeria de Materials (Gemat), Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain.
| | - C Castells-Sala
- Grup d'Enginyeria de Materials (Gemat), Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain
| | - S Borrós
- Grup d'Enginyeria de Materials (Gemat), Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain
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25
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Lin Z, Cheng Y, Wang RJ, Du J, Volovych O, Li JC, Hu Y, Lu ZY, Lu Z, Zou Z. A Metalloprotease Homolog Venom Protein From a Parasitoid Wasp Suppresses the Toll Pathway in Host Hemocytes. Front Immunol 2018; 9:2301. [PMID: 30405599 PMCID: PMC6206080 DOI: 10.3389/fimmu.2018.02301] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 09/17/2018] [Indexed: 12/18/2022] Open
Abstract
Parasitoid wasps depend on a variety of maternal virulence factors to ensure successful parasitism. Encapsulation response carried out by host hemocytes is one of the major host immune responses toward limiting endoparasitoid wasp offspring production. We found that VRF1, a metalloprotease homolog venom protein identified from the endoparasitoid wasp, Microplitis mediator, could modulate egg encapsulation in its host, the cotton bollworm, Helicoverpa armigera. Here, we show that the VRF1 proenzyme is cleaved after parasitism, and that the C-terminal fragment containing the catalytic domain enters host hemocytes 6 h post-parasitism. Furthermore, using yeast two-hybrid and pull-down assays, VRF1 is shown to interact with the H. armigera NF-κB factor, Dorsal. We also show that overexpressed of VRF1 in an H. armigera cell line cleaved Dorsal in vivo. Taken together, our results have revealed a novel mechanism by which a component of endoparasitoid wasp venom interferes with the Toll signaling pathway in the host hemocytes.
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Affiliation(s)
- Zhe Lin
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yang Cheng
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Rui-Juan Wang
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Jie Du
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Olga Volovych
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Jian-Cheng Li
- Institute of Plant Protection of Hebei Academy of Agriculture and Forestry Sciences, Baoding, China
| | - Yang Hu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zi-Yun Lu
- Institute of Plant Protection of Hebei Academy of Agriculture and Forestry Sciences, Baoding, China
| | - Zhiqiang Lu
- Department of Entomology, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Zhen Zou
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
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26
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Francia V, Aliyandi A, Salvati A. Effect of the development of a cell barrier on nanoparticle uptake in endothelial cells. NANOSCALE 2018; 10:16645-16656. [PMID: 30155550 DOI: 10.1039/c8nr03171a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
In order to improve the current success of nanomedicine, a better understanding of how nano-sized materials interact with and are processed by cells is required. Typical in vitro nanoparticle-cell interaction studies often make use of cells cultured at different cell densities. However, in vivo, for their successful delivery to the target tissue, nanomedicines need to overcome several barriers, such as endothelial and epithelial cell barriers. Unlike sub-confluent or confluent cell cultures, cell barriers are tight cell monolayers, expressing a series of specialized tight junction proteins between adjacent cells to limit paracellular transport and ensure close cell-to-cell interactions. A clear understanding on how the development of cells into a cell barrier may affect the uptake of nano-sized drug carriers is still missing. To this aim, here, human primary umbilical vein endothelial cells (HUVEC) are used as a model cell line to form endothelial cell barriers. Then, nanoparticle uptake is assessed in the developed endothelial barriers and compared to the uptake in sub-confluent or confluent HUVEC cultures. The results clearly show that the organization of cells into a cell barrier leads to a differential gene expression of endocytic markers, and - interestingly - this is accompanied by reduced nanoparticle uptake levels. Transport inhibitors are used to characterise the mechanisms involved in the uptake. However, we show that some of them can strongly compromise barrier integrity, thus impairing the interpretation of the outcomes, and overall, only a partial inhibition of nanoparticle uptake could be obtained.
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Affiliation(s)
- Valentina Francia
- Groningen Research Institute of Pharmacy, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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27
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Lu Q, Grotzke JE, Cresswell P. A novel probe to assess cytosolic entry of exogenous proteins. Nat Commun 2018; 9:3104. [PMID: 30082832 PMCID: PMC6079096 DOI: 10.1038/s41467-018-05556-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 07/06/2018] [Indexed: 01/08/2023] Open
Abstract
Dendritic cells use a specialized pathway called cross-presentation to activate CD8+ T cells by presenting peptides from exogenous protein antigens on major histocompatibility complex class I molecules. Considerable evidence suggests that internalized antigens cross endocytic membranes to access cytosolic proteasomes for processing. The mechanism of protein dislocation represents a major unsolved problem. Here we describe the development of a sensitive reporter substrate, an N-glycosylated variant of Renilla luciferase fused to the Fc region of human IgG1. The luciferase variant is designed to be enzymatically inactive when glycosylated, but active after the asparagine to aspartic acid conversion that occurs upon deglycosylation by the cytosolic enzyme N-glycanase-1. The generation of cytosolic luminescence depends on internalization, deglycosylation, the cytosolic AAA-ATPase VCP/p97, and the cytosolic chaperone HSP90. By incorporating a T cell epitope into the fusion protein, we demonstrate that antigen dislocation into the cytosol is the rate limiting step in cross-presentation.
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Affiliation(s)
- Qiao Lu
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Jeff E Grotzke
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Peter Cresswell
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, 06520, USA.
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28
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Sandvig K, Kavaliauskiene S, Skotland T. Clathrin-independent endocytosis: an increasing degree of complexity. Histochem Cell Biol 2018; 150:107-118. [PMID: 29774430 PMCID: PMC6096564 DOI: 10.1007/s00418-018-1678-5] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2018] [Indexed: 11/03/2022]
Abstract
This article aims at providing an update on the complexity of clathrin-independent endocytosis. It is now almost 30 years since we first wrote a review about its existence; at that time many people believed that with the exception of macropinocytosis, which will only be briefly mentioned in this review, all uptake could be accounted for by clathrin-dependent endocytosis. Now it is generally accepted that there are different clathrin-independent mechanisms, some of them regulated by ligands and membrane lipid composition. They can be both dynamin-dependent and -independent, meaning that the uptake cannot be accounted for by caveolae and other dynamin-dependent processes such as tubular structures that can be induced by toxins, e.g. Shiga toxin, or the fast endophilin mediated endocytosis recently described. Caveolae seem to be mostly quite stable structures with other functions than endocytosis, but evidence suggests that they may have cell-type dependent functions. Although several groups have been working on endocytic mechanisms for years, and new advanced methods have improved our ability to study mechanistic details, there are still a number of important questions we need to address, such as: How many endocytic mechanisms does a cell have? How quantitatively important are they? What about the complexity in polarized cells where clathrin-independent endocytosis is differentially regulated on the apical and basolateral poles? These questions are not easy to answer since one and the same molecule may contribute to more than one process, and manipulating one mechanism can affect another. Also, several inhibitors of endocytic processes commonly used turn out to be less specific than originally thought. We will here describe the current view of clathrin-independent endocytic processes and the challenges in studying them.
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Affiliation(s)
- Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379, Oslo, Norway.
- Department of Molecular Biosciences, University of Oslo, 0316, Oslo, Norway.
| | - Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379, Oslo, Norway
| | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379, Oslo, Norway
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29
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Abstract
RNA interference (RNAi) is a fundamental cellular process for the posttranscriptional regulation of gene expression. RNAi can exogenously be modulated by small RNA oligonucleotides, such as microRNAs (miRNAs) and small interfering RNAs (siRNAs), or by antisense oligonucleotides. These small oligonucleotides provided the scientific community with powerful and versatile tools to turn off the expression of genes of interest, and hold out the promise of new therapeutic solutions against a wide range of gene-associated pathologies. However, unmodified nucleic acids are highly instable in biological systems, and their weak interaction with plasma proteins confers an unfavorable pharmacokinetics. In this review, we first provide an overview of the most efficient chemical strategies that, over the past 30 years, have been used to significantly improve the therapeutic potential of oligonucleotides. Oligonucleotides targeting and delivery technologies are then presented, including covalent conjugates between oligonucleotides and targeting ligand, and noncovalent association with lipid or polymer nanoparticles. Finally, we specifically focus on the endosomal escape step, which represents a major stumbling block for the effective use of oligonucleotides as therapeutic agents. The need for approaches to quantitatively measure endosomal escape and cytosolic arrival of biomolecules is discussed in the context of the development of efficient oligonucleotide targeting and delivery vectors.
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Affiliation(s)
- Ludger Johannes
- Institut Curie, PSL Research University , Cellular and Chemical Biology, U1143 INSERM, UMR3666 CNRS, Paris, France
| | - Marco Lucchino
- Institut Curie, PSL Research University , Cellular and Chemical Biology, U1143 INSERM, UMR3666 CNRS, Paris, France
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30
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Deng C, Xiong J, Gu X, Chen X, Wu S, Wang Z, Wang D, Tu J, Xie J. Novel recombinant immunotoxin of EGFR specific nanobody fused with cucurmosin, construction and antitumor efficiency in vitro. Oncotarget 2018; 8:38568-38580. [PMID: 28445134 PMCID: PMC5503554 DOI: 10.18632/oncotarget.16930] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 03/24/2017] [Indexed: 11/25/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) overexpression is related to the increased aggressiveness, metastases, and poor prognosis in various cancers. In this study, we successfully constructed a new EGFR nanobody-based immunotoxin rE/CUS containing cucurmosin (CUS), The immunotoxin was expressed by prokaryotic system and we obtained a yield of 5 mg protein per liter expression medium. The percentage of it's binding ability totumor cell lines A549, HepG2, SW116, which highly expressed EGFR was 55.6%, 79.6% and 97.1%, respectively, but SW620 was only 4.45%. rE/CUS has the ability to bind A549, HepG2, SW116 cells specifically, and the antigen binding capability was not affected because of extra part of CUS component. The rE/CUS significantly inhibited the cell viability against EGFR over expression tumor cell lines in a dose-and time-dependent manner. Moreover, rE/CUS also induced apoptosis of HepG2 and A549 mightily. Our results demonstrate that rE/CUS is a potential therapeutic strategy for treating EGFR-positive solid tumors.
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Affiliation(s)
- Cuimin Deng
- Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian, China
| | - Jiani Xiong
- Department of Oncology, Fujian Medical University Union Hospital, Fuzhou, Fujian, China
| | - Xiaofan Gu
- Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian, China
| | - Xiaoying Chen
- Department of Experimental Teaching Center of Basic Medical Science, Fujian Medical University, Fuzhou, Fujian, China
| | - Shuifa Wu
- Department of Pharmacology, The 180th Hospital of PLA, Quanzhou, Fujian, China
| | - Zhe Wang
- Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian, China
| | - Duanduan Wang
- Department of Breast Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian, China
| | - Jinjin Tu
- Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian, China
| | - Jieming Xie
- Department of Pharmacology, Fujian Medical University, Fuzhou, Fujian, China
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31
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Dai W, Wu Y, Bi J, Wang S, Li F, Kong W, Barbier J, Cintrat JC, Gao F, Gillet D, Su W, Jiang C. Antiviral Effects of ABMA against Herpes Simplex Virus Type 2 In Vitro and In Vivo. Viruses 2018. [PMID: 29522484 PMCID: PMC5869512 DOI: 10.3390/v10030119] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Herpes simplex virus type 2 (HSV-2) is the causative pathogen of genital herpes and is closely associated with the occurrence of cervical cancer and human immunodeficiency virus (HIV) infection. The absence of an effective vaccine and the emergence of drug resistance to commonly used nucleoside analogs emphasize the urgent need for alternative antivirals against HSV-2. Recently, ABMA [1-adamantyl (5-bromo-2-methoxybenzyl) amine] has been demonstrated to be an inhibitor of several pathogens exploiting host-vesicle transport, which also participates in the HSV-2 lifecycle. Here, we showed that ABMA inhibited HSV-2-induced cytopathic effects and plaque formation with 50% effective concentrations of 1.66 and 1.08 μM, respectively. We also preliminarily demonstrated in a time of compound addition assay that ABMA exerted a dual antiviral mechanism by impairing virus entry, as well as the late stages of the HSV-2 lifecycle. Furthermore, in vivo studies showed that ABMA protected BALB/c mice from intravaginal HSV-2 challenge with an improved survival rate of 50% at 5 mg/kg (8.33% for the untreated virus infected control). Consequently, our study has identified ABMA as an effective inhibitor of HSV-2, both in vitro and in vivo, for the first time and presents an alternative to nucleoside analogs for HSV-2 infection treatment.
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Affiliation(s)
- Wenwen Dai
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Yu Wu
- SIMOPRO, CEA, Université Paris-Saclay, F-91191 Gif Sur Yvette, France.
| | - Jinpeng Bi
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Shuai Wang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Fang Li
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Wei Kong
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Julien Barbier
- SIMOPRO, CEA, Université Paris-Saclay, F-91191 Gif Sur Yvette, France.
| | | | - Feng Gao
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Daniel Gillet
- SIMOPRO, CEA, Université Paris-Saclay, F-91191 Gif Sur Yvette, France.
| | - Weiheng Su
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
| | - Chunlai Jiang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, Jilin, China.
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32
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Kavaliauskiene S, Torgersen ML, Lingelem ABD, Klokk TI, Lintonen T, Simolin H, Ekroos K, Skotland T, Sandvig K. Cellular effects of fluorodeoxyglucose: Global changes in the lipidome and alteration in intracellular transport. Oncotarget 2018; 7:79885-79900. [PMID: 27829218 PMCID: PMC5346758 DOI: 10.18632/oncotarget.13089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 10/21/2016] [Indexed: 11/29/2022] Open
Abstract
2-fluoro-2-deoxy-D-glucose (FDG), labeled with 18F radioisotope, is the most common imaging agent used for positron emission tomography (PET) in oncology. However, little is known about the cellular effects of FDG. Another glucose analogue, 2-deoxy-D-glucose (2DG), has been shown to affect many cellular functions, including intracellular transport and lipid metabolism, and has been found to improve the efficacy of cancer chemotherapeutic agents in vivo. Thus, in the present study, we have investigated cellular effects of FDG with the focus on changes in cellular lipids and intracellular transport. By quantifying more than 200 lipids from 17 different lipid classes in HEp-2 cells and by analyzing glycosphingolipids from MCF-7, HT-29 and HBMEC cells, we have discovered that FDG treatment inhibits glucosylceramide synthesis and thus reduces cellular levels of glycosphingolipids. In addition, in HEp-2 cells the levels and/or species composition of other lipid classes, namely diacylglycerols, phosphatidic acids and phosphatidylinositols, were found to change upon treatment with FDG. Furthermore, we show here that FDG inhibits retrograde Shiga toxin transport and is much more efficient in protecting cells against the toxin than 2DG. In summary, our data reveal novel effects of FDG on cellular transport and glycosphingolipid metabolism, which suggest a potential clinical application of FDG as an adjuvant for cancer chemotherapy.
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Affiliation(s)
- Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Maria Lyngaas Torgersen
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Anne Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Tove Irene Klokk
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
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33
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ABMA, a small molecule that inhibits intracellular toxins and pathogens by interfering with late endosomal compartments. Sci Rep 2017; 7:15567. [PMID: 29138439 PMCID: PMC5686106 DOI: 10.1038/s41598-017-15466-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/24/2017] [Indexed: 12/30/2022] Open
Abstract
Intracellular pathogenic microorganisms and toxins exploit host cell mechanisms to enter, exert their deleterious effects as well as hijack host nutrition for their development. A potential approach to treat multiple pathogen infections and that should not induce drug resistance is the use of small molecules that target host components. We identified the compound 1-adamantyl (5-bromo-2-methoxybenzyl) amine (ABMA) from a cell-based high throughput screening for its capacity to protect human cells and mice against ricin toxin without toxicity. This compound efficiently protects cells against various toxins and pathogens including viruses, intracellular bacteria and parasite. ABMA provokes Rab7-positive late endosomal compartment accumulation in mammalian cells without affecting other organelles (early endosomes, lysosomes, the Golgi apparatus, the endoplasmic reticulum or the nucleus). As the mechanism of action of ABMA is restricted to host-endosomal compartments, it reduces cell infection by pathogens that depend on this pathway to invade cells. ABMA may represent a novel class of broad-spectrum compounds with therapeutic potential against diverse severe infectious diseases.
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34
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Routes for Drug Translocation Across the Blood-Brain Barrier: Exploiting Peptides as Delivery Vectors. J Pharm Sci 2017; 106:2326-2334. [DOI: 10.1016/j.xphs.2017.04.080] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/21/2017] [Accepted: 04/24/2017] [Indexed: 01/17/2023]
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35
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Stolle AS, Norkowski S, Körner B, Schmitz J, Lüken L, Frankenberg M, Rüter C, Schmidt MA. T3SS-Independent Uptake of the Short-Trip Toxin-Related Recombinant NleC Effector of Enteropathogenic Escherichia coli Leads to NF-κB p65 Cleavage. Front Cell Infect Microbiol 2017; 7:119. [PMID: 28451521 PMCID: PMC5390045 DOI: 10.3389/fcimb.2017.00119] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 03/23/2017] [Indexed: 12/15/2022] Open
Abstract
Effector proteins secreted by the type 3 secretion system (T3SS) of pathogenic bacteria have been shown to precisely modulate important signaling cascades of the host for the benefit of the pathogens. Among others, the non-LEE encoded T3SS effector protein NleC of enteropathogenic Escherichia coli (EPEC) is a Zn-dependent metalloprotease and suppresses innate immune responses by directly targeting the NF-κB signaling pathway. Many pathogenic bacteria release potent bacterial toxins of the A-B type, which-in contrast to the direct cytoplasmic injection of T3SS effector proteins-are released first into the environment. In this study, we found that NleC displays characteristics of bacterial A-B toxins, when applied to eukaryotic cells as a recombinant protein. Although lacking a B subunit, that typically mediates the uptake of toxins, recombinant NleC (rNleC) induces endocytosis via lipid rafts and follows the endosomal-lysosomal pathway. The conformation of rNleC is altered by low pH to facilitate its escape from acidified endosomes. This is reminiscent of the homologous A-B toxin AIP56 of the fish pathogen Photobacterium damselae piscicida (Phdp). The recombinant protease NleC is functional inside eukaryotic cells and cleaves p65 of the NF-κB pathway. Here, we describe the endocytic uptake mechanism of rNleC, characterize its intracellular trafficking and demonstrate that its specific activity of cleaving p65 requires activation of host cells e.g., by IL1β. Further, we propose an evolutionary link between some T3SS effector proteins and bacterial toxins from apparently unrelated bacteria. In summary, these properties might suggest rNleC as an interesting candidate for future applications as a potential therapeutic against immune disorders.
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Affiliation(s)
- Anne-Sophie Stolle
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Stefanie Norkowski
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Britta Körner
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Jürgen Schmitz
- Institute of Experimental Pathology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Lena Lüken
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Maj Frankenberg
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - Christian Rüter
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
| | - M Alexander Schmidt
- Institute of Infectiology, Center for Molecular Biology of Inflammation, University of MünsterMünster, Germany
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36
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Li XP, Tumer NE. Differences in Ribosome Binding and Sarcin/Ricin Loop Depurination by Shiga and Ricin Holotoxins. Toxins (Basel) 2017; 9:toxins9040133. [PMID: 28398250 PMCID: PMC5408207 DOI: 10.3390/toxins9040133] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/28/2017] [Accepted: 04/05/2017] [Indexed: 11/16/2022] Open
Abstract
Both ricin and Shiga holotoxins display no ribosomal activity in their native forms and need to be activated to inhibit translation in a cell-free translation inhibition assay. This is because the ribosome binding site of the ricin A chain (RTA) is blocked by the B subunit in ricin holotoxin. However, it is not clear why Shiga toxin 1 (Stx1) or Shiga toxin 2 (Stx2) holotoxin is not active in a cell-free system. Here, we compare the ribosome binding and depurination activity of Stx1 and Stx2 holotoxins with the A1 subunits of Stx1 and Stx2 using either the ribosome or a 10-mer RNA mimic of the sarcin/ricin loop as substrates. Our results demonstrate that the active sites of Stx1 and Stx2 holotoxins are blocked by the A2 chain and the B subunit, while the ribosome binding sites are exposed to the solvent. Unlike ricin, which is enzymatically active, but cannot interact with the ribosome, Stx1 and Stx2 holotoxins are enzymatically inactive but can interact with the ribosome.
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Affiliation(s)
- Xiao-Ping Li
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
| | - Nilgun E Tumer
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
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37
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Bhide GP, Prehna G, Ramirez BE, Colley KJ. The Polybasic Region of the Polysialyltransferase ST8Sia-IV Binds Directly to the Neural Cell Adhesion Molecule, NCAM. Biochemistry 2017; 56:1504-1517. [PMID: 28233978 DOI: 10.1021/acs.biochem.6b01221] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polysialic acid (polySia) is a unique post-translational modification found on a small set of mammalian glycoproteins. Composed of long chains of α2,8-linked sialic acid, this large, negatively charged polymer attenuates protein and cell adhesion and modulates signaling mediated by its carriers and proteins that interact with these carriers. PolySia is crucial for the proper development of the nervous system and is upregulated during tissue regeneration and in highly invasive cancers. Our laboratory has previously shown that the neural cell adhesion molecule, NCAM, has an acidic surface patch in its first fibronectin type III repeat (FN1) that is critical for the polysialylation of N-glycans on the adjacent immunoglobulin domain (Ig5). We have also identified a polysialyltransferase (polyST) polybasic region (PBR) that may mediate substrate recognition. However, a direct interaction between the NCAM FN1 acidic patch and the polyST PBR has yet to be demonstrated. Here, we have probed this interaction using isothermal titration calorimetry and nuclear magnetic resonance (NMR) spectroscopy. We observe direct and specific binding between FN1 and the PBR peptide that is dependent upon acidic residues in FN1 and basic residues of the PBR. NMR titration experiments verified the role of the FN1 acidic patch in the recognition of the PBR and suggest a conformational change of the Ig5-FN1 linker region following binding of the PBR to the acidic patch. Finally, mutation of residues identified by NMR titration experiments impacts NCAM polysialylation, supporting their mechanistic role in protein-specific polysialylation.
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Affiliation(s)
- Gaurang P Bhide
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Gerd Prehna
- Center for Structural Biology, Research Resources Center, University of Illinois at Chicago , Chicago, Illinois 60607, United States.,Department of Microbiology and Immunology, University of Illinois at Chicago , Chicago, Illinois 60612, United States
| | - Benjamin E Ramirez
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago , Chicago, Illinois 60607, United States.,Center for Structural Biology, Research Resources Center, University of Illinois at Chicago , Chicago, Illinois 60607, United States
| | - Karen J Colley
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago , Chicago, Illinois 60607, United States
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38
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A Cell-Based Fluorescent Assay to Detect the Activity of AB Toxins that Inhibit Protein Synthesis. Methods Mol Biol 2017; 1600:25-36. [PMID: 28478554 DOI: 10.1007/978-1-4939-6958-6_3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Many AB toxins elicit a cytotoxic effect involving the inhibition of protein synthesis. In this chapter, we describe a simple cell-based fluorescent assay to detect and quantify the inhibition of protein synthesis. The assay can also identify and characterize toxin inhibitors.
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39
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Liu X, Zhang P, Rödl W, Maier K, Lächelt U, Wagner E. Toward Artificial Immunotoxins: Traceless Reversible Conjugation of RNase A with Receptor Targeting and Endosomal Escape Domains. Mol Pharm 2016; 14:1439-1449. [PMID: 28457141 DOI: 10.1021/acs.molpharmaceut.6b00701] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The specific transport of bioactive proteins into designated target cells is an interesting and challenging perspective for the generation of innovative biopharmaceuticals. Natural protein cytotoxins perform this task with outstanding efficacy. They enter cells with receptor-targeted specificity, respond to changing intracellular microenvironments, and by various mechanisms translocate their cytotoxic protein subunit into the cytosol. Here we imitate this toxin-based delivery strategy in an artificial setting, by bioreversible conjugation of a cytotoxic cargo protein (RNase A) with receptor-targeting PEG-folate and the pH-specific endosomolytic peptide INF7 as synthetic delivery domains. Covalent modification of the cargo protein was achieved using the pH-labile AzMMMan linker and copper-free click chemistry with DBCO-modified delivery modules. This linkage is supposed to enable traceless intracellular release of the RNase A after exposure to the endosomal weakly acidic environment. Delivery of RNase A via this polycation-free delivery strategy resulted in high cytotoxicity against receptor-positive KB tumor cells only when both PEG-folate and INF7 were attached.
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Affiliation(s)
- Xiaowen Liu
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Peng Zhang
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany.,Nanosystems Initiative Munich , Schellingstrasse 4, D-80799 Munich, Germany
| | - Wolfgang Rödl
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Kevin Maier
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany
| | - Ulrich Lächelt
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany.,Nanosystems Initiative Munich , Schellingstrasse 4, D-80799 Munich, Germany
| | - Ernst Wagner
- Pharmaceutical Biotechnology, Center for System-based Drug Research and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, D-81377 Munich, Germany.,Nanosystems Initiative Munich , Schellingstrasse 4, D-80799 Munich, Germany
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Conserved Arginines at the P-Protein Stalk Binding Site and the Active Site Are Critical for Ribosome Interactions of Shiga Toxins but Do Not Contribute to Differences in the Affinity of the A1 Subunits for the Ribosome. Infect Immun 2016; 84:3290-3301. [PMID: 27600507 DOI: 10.1128/iai.00630-16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 08/30/2016] [Indexed: 11/20/2022] Open
Abstract
The A1 subunits of Shiga toxin 1 (Stx1A1) and Shiga toxin 2 (Stx2A1) interact with the conserved C termini of ribosomal-stalk P-proteins to remove a specific adenine from the sarcin/ricin loop. We previously showed that Stx2A1 has higher affinity for the ribosome and higher catalytic activity than Stx1A1. To determine if conserved arginines at the distal face of the active site contribute to the higher affinity of Stx2A1 for the ribosome, we mutated Arg172, Arg176, and Arg179 in both toxins. We show that Arg172 and Arg176 are more important than Arg179 for the depurination activity and toxicity of Stx1A1 and Stx2A1. Mutation of a single arginine reduced the depurination activity of Stx1A1 more than that of Stx2A1. In contrast, mutation of at least two arginines was necessary to reduce depurination by Stx2A1 to a level similar to that of Stx1A1. R176A and R172A/R176A mutations eliminated interaction of Stx1A1 and Stx2A1 with ribosomes and with the stalk, while mutation of Arg170 at the active site reduced the binding affinity of Stx1A1 and Stx2A1 for the ribosome, but not for the stalk. These results demonstrate that conserved arginines at the distal face of the active site are critical for interactions of Stx1A1 and Stx2A1 with the stalk, while a conserved arginine at the active site is critical for non-stalk-specific interactions with the ribosome. Arginine mutations at either site reduced ribosome interactions of Stx1A1 and Stx2A1 similarly, indicating that conserved arginines are critical for ribosome interactions but do not contribute to the higher affinity of Stx2A1 for the ribosome.
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41
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Progida C, Bakke O. Bidirectional traffic between the Golgi and the endosomes - machineries and regulation. J Cell Sci 2016; 129:3971-3982. [PMID: 27802132 DOI: 10.1242/jcs.185702] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The bidirectional transport between the Golgi complex and the endocytic pathway has to be finely regulated in order to ensure the proper delivery of newly synthetized lysosomal enzymes and the return of sorting receptors from degradative compartments. The high complexity of these routes has led to experimental difficulties in properly dissecting and separating the different pathways. As a consequence, several models have been proposed during the past decades. However, recent advances in our understanding of endosomal dynamics have helped to unify these different views. We provide here an overview of the current insights into the transport routes between Golgi and endosomes in mammalian cells. The focus of the Commentary is on the key molecules involved in the trafficking pathways between these intracellular compartments, such as Rab proteins and sorting receptors, and their regulation. A proper understanding of the bidirectional traffic between the Golgi complex and the endolysosomal system is of uttermost importance, as several studies have demonstrated that mutations in the factors involved in these transport pathways result in various pathologies, in particular lysosome-associated diseases and diverse neurological disorders, such as Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Cinzia Progida
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Oddmund Bakke
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
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42
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Zilbermintz L, Leonardi W, Tran SH, Zozaya J, Mathew-Joseph A, Liem S, Levitin A, Martchenko M. Cross-inhibition of pathogenic agents and the host proteins they exploit. Sci Rep 2016; 6:34846. [PMID: 27703274 PMCID: PMC5050486 DOI: 10.1038/srep34846] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/19/2016] [Indexed: 11/09/2022] Open
Abstract
The major limitations of pathogen-directed therapies are the emergence of drug-resistance and their narrow spectrum of coverage. A recently applied approach directs therapies against host proteins exploited by pathogens in order to circumvent these limitations. However, host-oriented drugs leave the pathogens unaffected and may result in continued pathogen dissemination. In this study we aimed to discover drugs that could simultaneously cross-inhibit pathogenic agents, as well as the host proteins that mediate their lethality. We observed that many pathogenic and host-assisting proteins belong to the same functional class. In doing so we targeted a protease component of anthrax toxin as well as host proteases exploited by this toxin. We identified two approved drugs, ascorbic acid 6-palmitate and salmon sperm protamine, that effectively inhibited anthrax cytotoxic protease and demonstrated that they also block proteolytic activities of host furin, cathepsin B, and caspases that mediate toxin's lethality in cells. We demonstrated that these drugs are broad-spectrum and reduce cellular sensitivity to other bacterial toxins that require the same host proteases. This approach should be generally applicable to the discovery of simultaneous pathogen and host-targeting inhibitors of many additional pathogenic agents.
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Affiliation(s)
| | | | | | - Josue Zozaya
- Keck Graduate Institute, Claremont, CA 91711, USA
| | | | - Spencer Liem
- Keck Graduate Institute, Claremont, CA 91711, USA
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43
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Lipid transfer proteins and the tuning of compartmental identity in the Golgi apparatus. Chem Phys Lipids 2016; 200:42-61. [DOI: 10.1016/j.chemphyslip.2016.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 06/21/2016] [Accepted: 06/22/2016] [Indexed: 11/23/2022]
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44
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Retrograde Transport from Early Endosomes to the trans-Golgi Network Enables Membrane Wrapping and Egress of Vaccinia Virus Virions. J Virol 2016; 90:8891-905. [PMID: 27466413 DOI: 10.1128/jvi.01114-16] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 07/18/2016] [Indexed: 02/01/2023] Open
Abstract
UNLABELLED The anterograde pathway, from the endoplasmic reticulum through the trans-Golgi network to the cell surface, is utilized by trans-membrane and secretory proteins. The retrograde pathway, which directs traffic in the opposite direction, is used following endocytosis of exogenous molecules and recycling of membrane proteins. Microbes exploit both routes: viruses typically use the anterograde pathway for envelope formation prior to exiting the cell, whereas ricin and Shiga-like toxins and some nonenveloped viruses use the retrograde pathway for cell entry. Mining a human genome-wide RNA interference (RNAi) screen revealed a need for multiple retrograde pathway components for cell-to-cell spread of vaccinia virus. We confirmed and extended these results while discovering that retrograde trafficking was required for virus egress rather than entry. Retro-2, a specific retrograde trafficking inhibitor of protein toxins, potently prevented spread of vaccinia virus as well as monkeypox virus, a human pathogen. Electron and confocal microscopy studies revealed that Retro-2 prevented wrapping of virions with an additional double-membrane envelope that enables microtubular transport, exocytosis, and actin polymerization. The viral B5 and F13 protein components of this membrane, which are required for wrapping, normally colocalize in the trans-Golgi network. However, only B5 traffics through the secretory pathway, suggesting that F13 uses another route to the trans-Golgi network. The retrograde route was demonstrated by finding that F13 was largely confined to early endosomes and failed to colocalize with B5 in the presence of Retro-2. Thus, vaccinia virus makes novel use of the retrograde transport system for formation of the viral wrapping membrane. IMPORTANCE Efficient cell-to-cell spread of vaccinia virus and other orthopoxviruses depends on the wrapping of infectious particles with a double membrane that enables microtubular transport, exocytosis, and actin polymerization. Interference with wrapping or subsequent steps results in severe attenuation of the virus. Some previous studies had suggested that the wrapping membrane arises from the trans-Golgi network, whereas others suggested an origin from early endosomes. Some nonenveloped viruses use retrograde trafficking for entry into the cell. In contrast, we provided evidence that retrograde transport from early endosomes to the trans-Golgi network is required for the membrane-wrapping step in morphogenesis of vaccinia virus and egress from the cell. The potent in vitro inhibition of this step by the drug Retro-2 suggests that derivatives with enhanced pharmacological properties might serve as useful antipoxviral agents.
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45
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Ryou JH, Sohn YK, Hwang DE, Park WY, Kim N, Heo WD, Kim MY, Kim HS. Engineering of bacterial exotoxins for highly efficient and receptor-specific intracellular delivery of diverse cargos. Biotechnol Bioeng 2016; 113:1639-46. [PMID: 26773973 DOI: 10.1002/bit.25935] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 01/14/2016] [Indexed: 01/27/2023]
Abstract
The intracellular delivery of proteins with high efficiency in a receptor-specific manner is of great significance in molecular medicine and biotechnology, but remains a challenge. Herein, we present the development of a highly efficient and receptor-specific delivery platform for protein cargos by combining the receptor binding domain of Escherichia coli Shiga-like toxin and the translocation domain of Pseudomonas aeruginosa exotoxin A. We demonstrated the utility and efficiency of the delivery platform by showing a cytosolic delivery of diverse proteins both in vitro and in vivo in a receptor-specific manner. In particular, the delivery system was shown to be effective for targeting an intracellular protein and consequently suppressing the tumor growth in xenograft mice. The present platform can be widely used for intracellular delivery of diverse functional macromolecules with high efficiency in a receptor-specific manner. Biotechnol. Bioeng. 2016;113: 1639-1646. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Jeong-Hyun Ryou
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Yoo-Kyoung Sohn
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Da-Eun Hwang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Woo-Yong Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Nury Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Won-Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Mi-Young Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Korea.
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46
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Dyer PD, Kotha AK, Gollings AS, Shorter SA, Shepherd TR, Pettit MW, Alexander BD, Getti GT, El-Daher S, Baillie L, Richardson SC. An in vitro evaluation of epigallocatechin gallate (eGCG) as a biocompatible inhibitor of ricin toxin. Biochim Biophys Acta Gen Subj 2016; 1860:1541-50. [DOI: 10.1016/j.bbagen.2016.03.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 03/10/2016] [Accepted: 03/20/2016] [Indexed: 10/22/2022]
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47
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Abstract
Apoptosis triggered by ricin toxin (RT) has previously been associated with certain cellular organellar compartments, but the diversity in the composition of the organellar proteins remains unclear. Here, we applied a shotgun proteomics strategy to examine the differential expression of proteins in the mitochondria, nuclei, and cytoplasm of HeLa cells treated and not treated with RT. Data were combined with a global bioinformatics analysis and experimental confirmations. A total of 3107 proteins were identified. Bioinformatics predictors (Proteome Analyst, WoLF PSORT, TargetP, MitoPred, Nucleo, MultiLoc, and k-nearest neighbor) and a Bayesian model that integrated these predictors were used to predict the locations of 1349 distinct organellar proteins. Our data indicate that the Bayesian model was more efficient than the individual implementation of these predictors. Additionally, a Biomolecular Interaction Network (BIN) analysis was used to identify 149 BIN subnetworks. Our experimental confirmations indicate that certain apoptosis-related proteins (e.g. cytochrome c, enolase, lamin B, Bax, and Drp1) were found to be translocated and had variable expression levels. These results provide new insights for the systematic understanding of RT-induced apoptosis responses.
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Affiliation(s)
- Peng Liao
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan Province, People's Republic of China Institute of Military Veterinary Science, Academy of Military Medical Science, Changchun, Jilin Province, People's Republic of China
| | - Yunhu Li
- Hunan Biological and Electromechanical Polytechnic, The Party and Government Office, Changsha, Hunan Province, People's Republic of China
| | - Hongyang Li
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan Province, People's Republic of China
| | - Wensen Liu
- Institute of Military Veterinary Science, Academy of Military Medical Science, Changchun, Jilin Province, People's Republic of China
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48
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Simon N, FitzGerald D. Immunotoxin Therapies for the Treatment of Epidermal Growth Factor Receptor-Dependent Cancers. Toxins (Basel) 2016; 8:toxins8050137. [PMID: 27153091 PMCID: PMC4885052 DOI: 10.3390/toxins8050137] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 04/20/2016] [Accepted: 04/22/2016] [Indexed: 12/17/2022] Open
Abstract
Many epithelial cancers rely on enhanced expression of the epidermal growth factor receptor (EGFR) to drive proliferation and survival pathways. Development of therapeutics to target EGFR signaling has been of high importance, and multiple examples have been approved for human use. However, many of the current small molecule or antibody-based therapeutics are of limited effectiveness due to the inevitable development of resistance and toxicity to normal tissues. Recombinant immunotoxins are therapeutic molecules consisting of an antibody or receptor ligand joined to a protein cytotoxin, combining the specific targeting of a cancer-expressed receptor with the potent cell killing of cytotoxic enzymes. Over the decades, many bacterial- or plant-based immunotoxins have been developed with the goal of targeting the broad range of cancers reliant upon EGFR overexpression. Many examples demonstrate excellent anti-cancer properties in preclinical development, and several EGFR-targeted immunotoxins have progressed to human trials. This review summarizes much of the past and current work in the development of immunotoxins for targeting EGFR-driven cancers.
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Affiliation(s)
- Nathan Simon
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, 37/5124 Bethesda, MD 20892, USA.
| | - David FitzGerald
- Biotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, 37/5124 Bethesda, MD 20892, USA.
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49
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Retargeting the Clostridium botulinum C2 toxin to the neuronal cytosol. Sci Rep 2016; 6:23707. [PMID: 27025362 PMCID: PMC4812341 DOI: 10.1038/srep23707] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/10/2016] [Indexed: 12/16/2022] Open
Abstract
Many biological toxins are known to attack specific cell types, delivering their enzymatic payloads to the cytosol. This process can be manipulated by molecular engineering of chimeric toxins. Using toxins with naturally unlinked components as a starting point is advantageous because it allows for the development of payloads separately from the binding/translocation components. Here the Clostridium botulinum C2 binding/translocation domain was retargeted to neural cell populations by deleting its non-specific binding domain and replacing it with a C. botulinum neurotoxin binding domain. This fusion protein was used to deliver fluorescently labeled payloads to Neuro-2a cells. Intracellular delivery was quantified by flow cytometry and found to be dependent on artificial enrichment of cells with the polysialoganglioside receptor GT1b. Visualization by confocal microscopy showed a dissociation of payloads from the early endosome indicating translocation of the chimeric toxin. The natural Clostridium botulinum C2 toxin was then delivered to human glioblastoma A172 and synchronized HeLa cells. In the presence of the fusion protein, native cytosolic enzymatic activity of the enzyme was observed and found to be GT1b-dependent. This retargeted toxin may enable delivery of therapeutics to peripheral neurons and be of use in addressing experimental questions about neural physiology.
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50
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A novel fully-human cytolytic fusion protein based on granzyme B shows in vitro cytotoxicity and ex vivo binding to solid tumors overexpressing the epidermal growth factor receptor. Cancer Lett 2016; 374:229-40. [PMID: 26912070 DOI: 10.1016/j.canlet.2016.02.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 02/10/2016] [Accepted: 02/11/2016] [Indexed: 12/28/2022]
Abstract
Human cytolytic fusion proteins (hCFPs) offer a promising immunotherapeutic approach for the treatment of solid tumors, avoiding the immunogenicity and undesirable side-effects caused by immunotoxins derived from plants or bacteria. The well-characterized human serine protease granzyme B has already been used as a therapeutic pro-apoptotic effector domain. We therefore developed a novel recombinant hCFP (GbR201K-scFv1711) consisting of an epidermal growth factor receptor-specific human antibody fragment and a granzyme B point mutant (R201K) that is insensitive to serpin B9 (PI9), a natural inhibitor of wild-type granzyme B that is often expressed in solid tumors. We found that GbR201K-scFv1711 selectively bound to epidermoid cancer and rhabdomyosarcoma cells and was rapidly internalized by them. Nanomolar concentrations of GbR201K-scFv1711 achieved the specific killing of epidermoid cancer cells by inducing apoptosis, and similar effects were observed in rhabdomyosarcoma cells when GbR201K-scFv1711 was combined with the endosomolytic substance chloroquine. The novel hCFP was stable in serum and bound to human rhabdomyosarcoma tissue ex vivo. These data confirm that GbR201K-scFv1711 is a promising therapeutic candidate suitable for further clinical investigation.
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