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Willy J Peumans - One of the best experts on this subject based on the ideXlab platform.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100 μg/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100g/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle. © 2007 Elsevier B.V. All rights reserved.
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deterrent activity of Plant Lectins on cowpea weevil callosobruchus maculatus f oviposition
Phytochemistry, 2006Co-Authors: Amin Sadeghi, Els J M Van Damme, Willy J Peumans, Guy SmaggheAbstract:A set of 14 Plant Lectins was screened in a binary choice bioassay for inhibitory activity on cowpea weevil Callosobruchus maculatus (F.) oviposition. Coating of chickpea seeds (Cicer arietinum L.) with a 0.05% (w/v) solution of Plant Lectins caused a significant reduction in egg laying. Control experiments with heat inactivated lectin and BSA indicated that the observed deterrent effects are specific and require carbohydrate-binding activity. However, no clear correlation could be established between deterrent activity and sugar-binding specificity/molecular structure of the Lectins. Increasing the insect density reduced the inhibitory effect of the Lectins confirming that female insects are capable of adjusting their oviposition rates as a function of host availability.
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marked depletion of glycosylation sites in hiv 1 gp120 under selection pressure by the mannose specific Plant Lectins of hippeastrum hybrid and galanthus nivalis
Molecular Pharmacology, 2005Co-Authors: Jan Balzarini, Els J M Van Damme, Willy J Peumans, Kristel Van Laethem, Sigrid Hatse, Erik De Clercq, Matheus Froeyen, A Bolmstedt, Dominique ScholsAbstract:The Plant Lectins from Hippeastrum hybrid (HHA) and Galanthus nivalis (GNA) are 50,000-D tetramers showing specificity for α-(1,3) and/or α-(1,6)-mannose oligomers. They inhibit HIV-1 infection at a 50% effective concentration of 0.2 to 0.3 μg/ml. Escalating HHA or GNA concentrations (up to 500 μg/ml) led to the isolation of three HIV-1(IIIB) strains in CEM T cell cultures that were highly resistant to HHA and GNA, several other related mannose-specific Plant Lectins, and the monoclonal antibody 2G12, modestly resistant to the mannose-specific cyanovirin, which is derived from a blue-green alga, but fully susceptible to other HIV entry inhibitors as well as HIV reverse transcriptase inhibitors. These mutant virus strains were devoid of up to seven or eight of 22 glycosylation sites in the viral envelope glycoprotein gp120 because of mutations at the Asn or Thr/Ser sites of the N -glycosylation motifs. In one of the strains, a novel glycosylation site was created near a deleted glycosylation site. The affected glycosylation sites were predominantly clustered in regions of gp120 that are not involved in the direct interaction with either CD4, CCR5, CXCR4, or gp41. The mutant viruses containing the deleted glycosylation sites were markedly more infectious in CEM T-cell cultures than wild-type virus.
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cytoplasmic nuclear Plant Lectins a new story
Trends in Plant Science, 2004Co-Authors: Els J M Van Damme, Annick Barre, Pierre Rouge, Willy J PeumansAbstract:Plant Lectins comprise a widespread group of carbohydrate-binding proteins that show a marked heterogeneity with respect to their molecular structure, sugar-binding specificity and temporal and spatial regulation. Until recently, the role of most Lectins was associated with their binding to foreign glycans in either recognition and/or defence-related phenomena. Over the past few years, evidence has accumulated to support the idea that when Plants are stimulated by specific biotic or abiotic stimuli they respond through the expression of cytoplasmic and/or nuclear Plant Lectins. The location and the regulation of the expression of these Lectins indicate that Lectins are involved in specific endogenous protein–carbohydrate interactions. These novel findings led to the challenging idea that Lectins might be involved in cellular regulation and signalling.
Els J M Van Damme - One of the best experts on this subject based on the ideXlab platform.
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signaling through Plant Lectins modulation of Plant immunity and beyond
Biochemical Society Transactions, 2018Co-Authors: Sofie Van Holle, Els J M Van DammeAbstract:Lectins constitute an abundant group of proteins that are present throughout the Plant kingdom. Only recently, genome-wide screenings have unraveled the multitude of different lectin sequences within one Plant species. It appears that Plants employ a plurality of Lectins, though relatively few Lectins have already been studied and functionally characterized. Therefore, it is very likely that the full potential of lectin genes in Plants is underrated. This review summarizes the knowledge of plasma membrane-bound Lectins in different biological processes (such as recognition of pathogen-derived molecules and symbiosis) and illustrates the significance of soluble intracellular Lectins and how they can contribute to Plant signaling. Altogether, the family of Plant Lectins is highly complex with an enormous diversity in biochemical properties and activities.
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History of Plant Lectin Research
Methods of Molecular Biology, 2014Co-Authors: Els J M Van DammeAbstract:Numerous Plant species are known to express one or more Lectins or proteins containing a lectin domain, enabling these proteins to select and bind specific carbohydrate structures. The group of Plant Lectins is quite heterogeneous since Lectins differ in their molecular structure, specificity for certain carbohydrate structures, and biological activities resulting therefrom. This chapter presents a short historical overview on how Plant lectin research has evolved over the years from a discipline aiming merely at the purification and characterization of Plant Lectins towards the application of Plant Lectins as tools in glycobiology.
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Plant insect interactions what can we learn from Plant Lectins
Archives of Insect Biochemistry and Physiology, 2010Co-Authors: Katrien Michiels, Els J M Van Damme, Guy SmaggheAbstract:Many Plant Lectins have high anti-insect potential. Although the effects of most Lectins are only moderately influencing development or population growth of the insect, some Lectins have strong insecticidal properties. In addition, some studies report a deterrent activity towards feeding and oviposition behavior. Transmission of Plant Lectins to the next trophic level has been investigated for several tritrophic interactions. Effects of Lectins with different sugar specificities can vary substantially with the insect species under investigation and with the experimental setup. Lectin binding in the insect is an essential step in exerting a toxic effect. Attempts have been made to study the interactions of Lectins in several insect tissues and to identify lectin-binding receptors. Ingested Lectins generally bind to parts of the insect gut. Furthermore, some Lectins such as the Galanthus nivalus agglutinin (GNA) cross the gut epithelium into the hemolymph and other tissues. Recently, several candidate lectin-binding receptors have been isolated from midgut extracts. To date little is known about the exact mechanism for insecticidal activity of Plant Lectins. However, insect glycobiology is an emerging research field and the recent technological advances in the analysis of lectin carbohydrate specificities and insect glycobiology will certainly lead to new insights in the interactions between Plant Lectins and insects, and to a better understanding of the molecular mechanisms involved. © 2010 Wiley Periodicals, Inc.
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nucleocytoplasmic Plant Lectins
Biochimica et Biophysica Acta, 2010Co-Authors: Nausicaa Lannoo, Els J M Van DammeAbstract:During the last decade it was unambiguously shown that Plants synthesize minute amounts of carbohydrate-binding proteins upon exposure to stress situations like drought, high salt, hormone treatment, pathogen attack or insect herbivory. In contrast to the 'classical' Plant Lectins, which are typically found in storage vacuoles or in the extracellular compartment this new class of Lectins is located in the cytoplasm and the nucleus. Based on these observations the concept was developed that lectin-mediated protein-carbohydrate interactions in the cytoplasm and the nucleus play an important role in the stress physiology of the Plant cell. Hitherto, six families of nucleocytoplasmic Lectins have been identified. This review gives an overview of our current knowledge on the occurrence of nucleocytoplasmic Plant Lectins. The carbohydrate-binding properties of these Lectins and potential ligands in the nucleocytoplasmic compartment are discussed in view of the physiological role of the Lectins in the Plant cell.
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natural products Plant Lectins as important tools in controlling pest insects
Biorational control of arthropod pests : application and resistance management, 2009Co-Authors: Gianni Vandenborre, Els J M Van Damme, Guy SmaggheAbstract:During the long course of interaction and co-evolution with herbivorous insects, Plants have evolved a broad range of defense mechanisms to counteract insect attack (Chen 2008). Next to the presence of structural defense barriers, Plants have developed several chemical defense strategies towards herbivorous insects. These defense chemicals include Plant secondary metabolites and proteins that can reduce the nutrient value of the Plant material or have a direct effect by interfering with the normal insect metabolism. One particular class of these defense proteins is Plant Lectins, a heterogeneous group of proteins that specifically interact with sugars (Peumans and Van Damme 1995; Czapla 1997; Van Damme et al. 2007, 2008). Many Plants including different food crops such as wheat, rice, potato, tomato, soybean and bean contain Lectins (Van Damme et al. 1998). Nowadays, the term Plant lectin is used for all Plant proteins possessing at least one non-catalytic domain, which binds reversibly to a specific mono- or oligosaccharide (Peumans and Van Damme 1995). Lectins from different Plant species often differ with respect to their molecular structure and specificity. Based on sequence similarity, Plant Lectins can be divided in different subgroups of structurally and evolutionary related proteins (Table 1).
Jan Balzarini - One of the best experts on this subject based on the ideXlab platform.
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the carbohydrate binding Plant Lectins and the non peptidic antibiotic pradimicin a target the glycans of the coronavirus envelope glycoproteins
Journal of Antimicrobial Chemotherapy, 2007Co-Authors: F J U M Van Der Meer, Jan Balzarini, C A M De Haan, N M P Schuurman, Bert Jan Haijema, Monique H Verheije, Berend Jan Bosch, Herman EgberinkAbstract:OBJECTIVES: Many enveloped viruses carry carbohydrate-containing proteins on their surface. These glycoproteins are key to the infection process as they are mediators of the receptor binding and membrane fusion of the virion with the host cell. Therefore, they are attractive therapeutic targets for the development of novel antiviral therapies. Recently, carbohydrate-binding agents (CBA) were shown to possess antiviral activity towards coronaviruses. The current study further elucidates the inhibitory mode of action of CBA. METHODS: Different strains of two coronaviruses, mouse hepatitis virus and feline infectious peritonitis virus, were exposed to CBA: the Plant Lectins Galanthus nivalis agglutinin, Hippeastrum hybrid agglutinin and Urtica dioica agglutinin (UDA) and the non-peptidic mannose-binding antibiotic pradimicin A. RESULTS AND CONCLUSIONS: Our results indicate that CBA target the two glycosylated envelope glycoproteins, the spike (S) and membrane (M) protein, of mouse hepatitis virus and feline infectious peritonitis virus. Furthermore, CBA did not inhibit virus-cell attachment, but rather affected virus entry at a post-binding stage. The sensitivity of coronaviruses towards CBA was shown to be dependent on the processing of the N-linked carbohydrates. Inhibition of mannosidases in host cells rendered the progeny viruses more sensitive to the mannose-binding agents and even to the N-acetylglucosamine-binding UDA. In addition, inhibition of coronaviruses was shown to be dependent on the cell-type used to grow the virus stocks. All together, these results show that CBA exhibit promising capabilities to inhibit coronavirus infections.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100 μg/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle.
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differential in vitro inhibitory activity against hiv 1 of alpha 1 3 and alpha 1 6 d mannose specific Plant Lectins implication for microbicide development
Journal of Translational Medicine, 2007Co-Authors: Hela Saidi, Jan Balzarini, Nadine Nasreddine, Mohammadali Jenabian, Maxime Lecerf, Dominique Schols, Corinne Krief, Laurent BelecAbstract:Background Plant Lectins such as Galanthus nivalis agglutinin (GNA) and Hippeastrum hybrid agglutinin (HHA) are natural proteins able to link mannose residues, and therefore inhibit HIV-target cell interactions. Plant Lectins are candidate for microbicide development.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100g/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle. © 2007 Elsevier B.V. All rights reserved.
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marked depletion of glycosylation sites in hiv 1 gp120 under selection pressure by the mannose specific Plant Lectins of hippeastrum hybrid and galanthus nivalis
Molecular Pharmacology, 2005Co-Authors: Jan Balzarini, Els J M Van Damme, Willy J Peumans, Kristel Van Laethem, Sigrid Hatse, Erik De Clercq, Matheus Froeyen, A Bolmstedt, Dominique ScholsAbstract:The Plant Lectins from Hippeastrum hybrid (HHA) and Galanthus nivalis (GNA) are 50,000-D tetramers showing specificity for α-(1,3) and/or α-(1,6)-mannose oligomers. They inhibit HIV-1 infection at a 50% effective concentration of 0.2 to 0.3 μg/ml. Escalating HHA or GNA concentrations (up to 500 μg/ml) led to the isolation of three HIV-1(IIIB) strains in CEM T cell cultures that were highly resistant to HHA and GNA, several other related mannose-specific Plant Lectins, and the monoclonal antibody 2G12, modestly resistant to the mannose-specific cyanovirin, which is derived from a blue-green alga, but fully susceptible to other HIV entry inhibitors as well as HIV reverse transcriptase inhibitors. These mutant virus strains were devoid of up to seven or eight of 22 glycosylation sites in the viral envelope glycoprotein gp120 because of mutations at the Asn or Thr/Ser sites of the N -glycosylation motifs. In one of the strains, a novel glycosylation site was created near a deleted glycosylation site. The affected glycosylation sites were predominantly clustered in regions of gp120 that are not involved in the direct interaction with either CD4, CCR5, CXCR4, or gp41. The mutant viruses containing the deleted glycosylation sites were markedly more infectious in CEM T-cell cultures than wild-type virus.
Herman Egberink - One of the best experts on this subject based on the ideXlab platform.
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the carbohydrate binding Plant Lectins and the non peptidic antibiotic pradimicin a target the glycans of the coronavirus envelope glycoproteins
Journal of Antimicrobial Chemotherapy, 2007Co-Authors: F J U M Van Der Meer, Jan Balzarini, C A M De Haan, N M P Schuurman, Bert Jan Haijema, Monique H Verheije, Berend Jan Bosch, Herman EgberinkAbstract:OBJECTIVES: Many enveloped viruses carry carbohydrate-containing proteins on their surface. These glycoproteins are key to the infection process as they are mediators of the receptor binding and membrane fusion of the virion with the host cell. Therefore, they are attractive therapeutic targets for the development of novel antiviral therapies. Recently, carbohydrate-binding agents (CBA) were shown to possess antiviral activity towards coronaviruses. The current study further elucidates the inhibitory mode of action of CBA. METHODS: Different strains of two coronaviruses, mouse hepatitis virus and feline infectious peritonitis virus, were exposed to CBA: the Plant Lectins Galanthus nivalis agglutinin, Hippeastrum hybrid agglutinin and Urtica dioica agglutinin (UDA) and the non-peptidic mannose-binding antibiotic pradimicin A. RESULTS AND CONCLUSIONS: Our results indicate that CBA target the two glycosylated envelope glycoproteins, the spike (S) and membrane (M) protein, of mouse hepatitis virus and feline infectious peritonitis virus. Furthermore, CBA did not inhibit virus-cell attachment, but rather affected virus entry at a post-binding stage. The sensitivity of coronaviruses towards CBA was shown to be dependent on the processing of the N-linked carbohydrates. Inhibition of mannosidases in host cells rendered the progeny viruses more sensitive to the mannose-binding agents and even to the N-acetylglucosamine-binding UDA. In addition, inhibition of coronaviruses was shown to be dependent on the cell-type used to grow the virus stocks. All together, these results show that CBA exhibit promising capabilities to inhibit coronavirus infections.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100 μg/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100g/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle. © 2007 Elsevier B.V. All rights reserved.
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mannose specific Plant Lectins from the amaryllidaceae family qualify as efficient microbicides for prevention of human immunodeficiency virus infection
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Jan Balzarini, Sigrid Hatse, Kurt Vermeire, Erik De Clercq, Herman Egberink, Katrien Princen, Stefano Aquaro, Carlo Federico Perno, Guy Van Den Mooter, Willy J PeumansAbstract:The Plant Lectins derived from Galanthus nivalis (Snowdrop) (GNA) and Hippeastrum hybrid (Amaryllis) (HHA) selectively inhibited a wide variety of human immunodeficiency virus type 1 (HIV-1) and HIV-2 strains and clinical (CXCR4- and CCR5-using) isolates in different cell types. They also efficiently inhibited infection of T lymphocytes by a variety of mutant virus strains. GNA and HHA markedly prevented syncytium formation between persistently infected HUT-78/HIV cells and uninfected T lymphocytes. The Plant Lectins did not measurably affect the antiviral activity of other clinically approved anti-HIV drugs used in the clinic when combined with these drugs. Short exposure of the Lectins to cell-free virus particles or persistently HIV-infected HUT-78 cells markedly decreased HIV infectivity and increased the protective (microbicidal) activity of the Plant Lectins. Flow cytometric analysis and monoclonal antibody binding studies and a PCR-based assay revealed that GNA and HHA do not interfere with CD4, CXCR4, CCR5, and DC-SIGN and do not specifically bind with the membrane of uninfected cells. Instead, GNA and HHA likely interrupt the virus entry process by interfering with the virus envelope glycoprotein. HHA and GNA are odorless, colorless, and tasteless, and they are not cytotoxic, antimetabolically active, or mitogenic to human primary T lymphocytes at concentrations that exceed their antivirally active concentrations by 2 to 3 orders of magnitude. GNA and HHA proved stable at high temperature (50°C) and low pH (5.0) for prolonged time periods and can be easily formulated in gel preparations for microbicidal use; they did not agglutinate human erythrocytes and were not toxic to mice when administered intravenously.
Marc Van Ranst - One of the best experts on this subject based on the ideXlab platform.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100 μg/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle.
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Plant Lectins are potent inhibitors of coronaviruses by interfering with two targets in the viral replication cycle
Antiviral Research, 2007Co-Authors: Els Keyaerts, Els J M Van Damme, Willy J Peumans, Jan Balzarini, Leen Vijgen, Christophe Pannecouque, Herman Egberink, Marc Van RanstAbstract:We describe the antiviral activity of Plant Lectins with specificity for different glycan structures against the severe acute respiratory syndrome coronavirus (SARS-CoV) and the feline infectious peritonitis virus (FIPV) in vitro. The SARS-CoV emerged in 2002 as an important cause of severe lower respiratory tract infection in humans, and FIPV infection causes a chronic and often fatal peritonitis in cats. A unique collection of 33 Plant Lectins with different specificities were evaluated. The Plant Lectins possessed marked antiviral properties against both coronaviruses with EC50 values in the lower microgram/ml range (middle nanomolar range), being non-toxic (CC50) at 50–100g/ml. The strongest anti-coronavirus activity was found predominantly among the mannose-binding Lectins. In addition, a number of galactose-, N-acetylgalactosamine-, glucose-, and N-acetylglucosamine-specific Plant agglutinines exhibited anti-coronaviral activity. A significant correlation (with an r-value of 0.70) between the EC50 values of the 10 mannose-specific Plant Lectins effective against the two coronaviruses was found. In contrast, little correlation was seen between the activity of other types of Lectins. Two targets of possible antiviral intervention were identified in the replication cycle of SARS-CoV. The first target is located early in the replication cycle, most probably viral attachment, and the second target is located at the end of the infectious virus cycle. © 2007 Elsevier B.V. All rights reserved.