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Isegawa Y. Activation of Immune and Antiviral Effects by Euglena Extracts: A Review. Foods 2023; 12:4438. [PMID: 38137241 PMCID: PMC10743201 DOI: 10.3390/foods12244438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/20/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
Influenza is an acute respiratory illness caused by influenza virus infection, which is managed using vaccines and antiviral drugs. Recently, the antiviral effects of plants and foods have gained attention. Euglena is a motile unicellular alga and eukaryotic photosynthetic microorganism. It has secondary chloroplasts and is a mixotroph able to feed by photosynthesis or phagocytosis. This review summarizes the influenza treatment effects of Euglena from the perspective of a functional food that is attracting attention. While it has been reported that Euglena contributes to suppressing blood sugar levels and ameliorates symptoms caused by stress by acting on the autonomic nervous system, the immunostimulatory and antiviral activities of Euglena have also been reported. In this review, I focused on the immunostimulation of antiviral activity via the intestinal environment and the suppression of viral replication in infected cells. The functions of specific components of Euglena, which also serves as the source of a wide range of nutrients such as vitamins, minerals, amino acids, unsaturated fatty acids, and β-1,3-glucan (paramylon), are also reviewed. Euglena has animal and plant properties and natural compounds with a wide range of functions, providing crucial information for improved antiviral strategies.
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Affiliation(s)
- Yuji Isegawa
- Department of Applied Biological Chemistry, Graduate School of Agriculture, Osaka Metropolitan University, Sakai, Osaka 599-8531, Japan
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2
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Kanazawa R, Morimoto R, Horio Y, Sumitani H, Isegawa Y. Inhibition of influenza virus replication by Apiaceae plants, with special reference to Peucedanum japonicum (Sacna) constituents. JOURNAL OF ETHNOPHARMACOLOGY 2022; 292:115243. [PMID: 35358620 DOI: 10.1016/j.jep.2022.115243] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/16/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Apiaceae plants possess various pharmacological properties, such as antimicrobial, antioxidant, hypoglycemic, hypolipidemic, anxiolytic, analgesic, anti-inflammatory, anti-convulsant, and anti-cancer activities; however, data on their antiviral activity are limited. Peucedanum japonicum, also known as Sacna, is a plant used as food and as a traditional folk medicine for treating coughs. However, the active components in the leaves of this plant are yet unexplored. AIM OF THE STUDY To assess Apiaceae plants, especially Peucedanum japonicum, with anti-viral activity, and the function and antiviral potential of Sacna constituents, considering the emergence of influenza virus strains resistant to the currently available drugs. MATERIALS AND METHODS We prepared grinds of the freeze-dried leaves and roots of the Apiaceae family and the hot water extracts. The antiviral activities of the extracts were determined by focus formation reduction assay. In the time-of-addition assay, the test medium containing Sacna extract at 2 mg/mL was added at -1 to 0 h (adsorption) or from 0 to 4, 4 to 8, or 0 to 8 h (replication). The Sacna extract was separated by reversed-phase flash column chromatography using an Isolera Spektra system. The antiviral activity of each fraction was then determined using the focus formation reduction assay. The active fraction was analyzed using an LC20ADXR high performance liquid chromatography system equipped with a microTOF-QII quadrupole time-of-flight tandem mass spectrometer. RESULTS All examined extracts of Apiaceae plants showed anti-influenza activity. Sacna extract most strongly inhibited the replication of influenza viruses. Individual components of Sacna possess antiviral activities against the influenza A/PR/8/34 virus. Sacna was found to inhibit the multiplication of A (H1N1 and H3N2) types and B types of influenza viruses, including amantadine-resistant and oseltamivir-resistant viruses. Sacna also inhibited influenza infection during viral replication. However, Sacna did not inhibit influenza infection during cell adsorption and did not suppress hemagglutination inhibition or cell fusion. Further, our findings suggest that the antiviral compounds in Sacna include flavonoids (quercetin and luteolin) and other polyphenols (caffeic acid, hymecromone, and umbelliferone). Although several effective compounds in Sacna inhibit multiple steps of viral replication, caffeic acid, which was increased by heat treatment at the time of extraction, significantly inhibited only the late period of viral growth, similar to the Sacna extract, indicating that it is the major component responsible for the antiviral activity of Sacna. CONCLUSIONS Apiaceae plants possess antiviral activity. Caffeic acid is the major component responsible for the antiviral activity of Sacna. To our knowledge, this is the first report regarding the anti-influenza virus activity of Sacna. Overall, these results indicate that Sacna has potential as a novel treatment against influenza A and B viruses.
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Affiliation(s)
- Ryoko Kanazawa
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, 663-8558, Japan
| | - Ryosuke Morimoto
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, 663-8558, Japan
| | - Yuka Horio
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, 663-8558, Japan
| | - Hidenobu Sumitani
- Toyo Institute of Food Technology, Kawanishi, Hyogo, 666-0026, Japan
| | - Yuji Isegawa
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, 663-8558, Japan.
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Downard KM. SEQUENCE-FREE PHYLOGENETICS WITH MASS SPECTROMETRY. MASS SPECTROMETRY REVIEWS 2022; 41:3-14. [PMID: 33169385 DOI: 10.1002/mas.21658] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
An alternative, more rapid, sequence-free approach to build phylogenetic trees has been conceived and implemented. Molecular phylogenetics has continued to mostly focus on improvement in tree construction based on gene sequence alignments. Here protein-based phylogenies are constructed using numerical data sets ("phylonumerics") representing the masses of peptide segments recorded in a mass mapping experiment. This truly sequence-free method requires no gene sequences, nor their alignment, to build the trees affording a considerable time and cost-saving to conventional phylogenetics methods. The approach also calculates single point amino acid mutations from a comparison of mass pairs from different maps in the data set and displays these at branch nodes across the tree together with their frequency. Studies of the consecutive, and near-consecutive, ancestral and descendant mutations across interconnected branches of a mass tree allow putative adaptive, epistatic, and compensatory mutations to be identified in order to investigate mechanisms associated with evolutionary processes and pathways. A side-by-side comparison of this sequence-free approach and conventional gene sequence phylogenetics is discussed.
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Affiliation(s)
- Kevin M Downard
- Infectious Disease Responses Laboratory, Prince of Wales Clinical Sciences, Medicine, University of New South Wales, Sydney, New South Wales, Australia
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4
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Antiviral Activity and Underlying Action Mechanism of Euglena Extract against Influenza Virus. Nutrients 2021; 13:nu13113911. [PMID: 34836165 PMCID: PMC8624635 DOI: 10.3390/nu13113911] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 12/16/2022] Open
Abstract
It is difficult to match annual vaccines against the exact influenza strain that is spreading in any given flu season. Owing to the emergence of drug-resistant viral strains, new approaches for treating influenza are needed. Euglena gracilis (hereinafter Euglena), microalga, used as functional foods and supplements, have been shown to alleviate symptoms of influenza virus infection in mice. However, the mechanism underlying the inhibitory action of microalgae against the influenza virus is unknown. Here, we aimed to study the antiviral activity of Euglena extract against the influenza virus and the underlying action mechanism using Madin–Darby canine kidney (MDCK) cells. Euglena extract strongly inhibited infection by all influenza virus strains examined, including those resistant to the anti-influenza drugs oseltamivir and amantadine. A time-of-addition assay revealed that Euglena extract did not affect the cycle of virus replication, and cell pretreatment or prolonged treatment of infected cells reduced the virus titer. Thus, Euglena extract may activate the host cell defense mechanisms, rather than directly acting on the influenza virus. Moreover, various minerals, mainly zinc, in Euglena extract were found to be involved in the antiviral activity of the extract. In conclusion, Euglena extract could be a potent agent for preventing and treating influenza.
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Park JH, Kim B, Antigua KJC, Jeong JH, Kim CI, Choi WS, Oh S, Kim CH, Kim EG, Choi YK, Baek YH, Song MS. Baloxavir-oseltamivir combination therapy inhibits the emergence of resistant substitutions in influenza A virus PA gene in a mouse model. Antiviral Res 2021; 193:105126. [PMID: 34217753 DOI: 10.1016/j.antiviral.2021.105126] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 06/23/2021] [Accepted: 06/30/2021] [Indexed: 12/12/2022]
Abstract
Baloxavir marboxil (BXM) treatment-emergent polymerase acid (PA) I38X amino acid substitution (AAS) in the resistant variants of influenza viruses raise concerns regarding their emergence and spread. This study investigated the impact of 1 or 5 mg/kg BXM and 25 mg/kg oseltamivir phosphate (OS) (single or combination therapy) on the occurrence of resistance-related substitutions during the sequential lung-to-lung passages of AH1N1)pdm09 virus in mice. Deep sequencing analysis revealed that 67% (n = 4/6) of the population treated with BXM single therapy (1 or 5 mg/kg) possessed the treatment-emergent PA-I38X AAS variants (I38T, I38S, and I38V). Notably, BXM-OS combination therapy impeded PA-I38X AAS emergence. Although the doses utilized in the mouse model may not be directly translated into the clinically equivalent doses of each drugs, these findings offer insights toward alternative therapies to mitigate the emergence of influenza antiviral resistance.
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Affiliation(s)
- Ji-Hyun Park
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Beomkyu Kim
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Khristine Joy C Antigua
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Ju Hwan Jeong
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Chang Il Kim
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Won-Suk Choi
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Sol Oh
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Chan Hyung Kim
- Department of Pharmacology, Chungbuk National University College of Medicine, Cheongju, Republic of Korea
| | - Eung-Gook Kim
- Department of Biochemistry, Chungbuk National University College of Medicine, Cheongju, Republic of Korea
| | - Young Ki Choi
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea
| | - Yun Hee Baek
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea.
| | - Min-Suk Song
- Department of Microbiology, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Republic of Korea.
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6
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Pedruzzi G, Rouzine IM. An evolution-based high-fidelity method of epistasis measurement: Theory and application to influenza. PLoS Pathog 2021; 17:e1009669. [PMID: 34153082 PMCID: PMC8248644 DOI: 10.1371/journal.ppat.1009669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 07/01/2021] [Accepted: 05/25/2021] [Indexed: 12/18/2022] Open
Abstract
Linkage effects in a multi-locus population strongly influence its evolution. The models based on the traveling wave approach enable us to predict the average speed of evolution and the statistics of phylogeny. However, predicting statistically the evolution of specific sites and pairs of sites in the multi-locus context remains a mathematical challenge. In particular, the effects of epistasis, the interaction of gene regions contributing to phenotype, is difficult to predict theoretically and detect experimentally in sequence data. A large number of false-positive interactions arises from stochastic linkage effects and indirect interactions, which mask true epistatic interactions. Here we develop a proof-of-principle method to filter out false-positive interactions. We start by demonstrating that the averaging of haplotype frequencies over multiple independent populations is necessary but not sufficient for epistatic detection, because it still leaves high numbers of false-positive interactions. To compensate for the residual stochastic noise, we develop a three-way haplotype method isolating true interactions. The fidelity of the method is confirmed analytically and on simulated genetic sequences evolved with a known epistatic network. The method is then applied to a large sequence database of neurominidase protein of influenza A H1N1 obtained from various geographic locations to infer the epistatic network responsible for the difference between the pre-pandemic virus and the pandemic strain of 2009. These results present a simple and reliable technique to measure epistatic interactions of any sign from sequence data. Interactions between genomic sites create a fitness landscape. The knowledge of topology and strength of interactions is vital for predicting the escape of viruses from drugs and immune response and their passing through fitness valleys. Many efforts have been invested into measuring these interactions from DNA sequence sets. Unfortunately, reproducibility of the results remains low due partly to a very small fraction of interaction pairs and partly to stochastic linkage noise masking true interactions. Here we propose a method to separate stochastic linkage and indirect interactions from epistatic interactions and apply it to influenza virus sequence data.
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Affiliation(s)
- Gabriele Pedruzzi
- Sorbonne Université, Institute de Biologie Paris-Seine, Laboratoire de Biologie Computationelle et Quantitative LCQB, Paris, France
| | - Igor M. Rouzine
- Sorbonne Université, Institute de Biologie Paris-Seine, Laboratoire de Biologie Computationelle et Quantitative LCQB, Paris, France
- * E-mail:
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7
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Downard KM. Protein phylogenetics with mass spectrometry. A comparison of methods. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2021; 13:1442-1454. [PMID: 33725067 DOI: 10.1039/d1ay00153a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Advances in protein mass spectrometry have provided the ability to identify and sequence proteins with unprecedented speed, sensitivity and accuracy. These benefits now offer advantages for studies of protein evolution and phylogeny avoiding the need to generate and align DNA sequences which can prove time consuming, costly and difficult in the case of large genomes and for highly diverse organisms. The methods of phylogenetic analysis using protein mass spectrometry can be classified into three categories: (1) de novo protein sequencing followed by multiple sequence alignment for classical phylogenetic reconstruction, (2) direct phylogenetic reconstruction using expressed protein mass profiles exploited in microbial biotyping applications, and (3) the construction of trees using proteolytic peptide mass map or fingerprint data. This review describes the three approaches together with the relevant tools and algorithms required to implement them. It also compares each of these alternative protein based methods alongside conventional gene sequence based phylogenetics.
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Affiliation(s)
- Kevin M Downard
- Infectious Disease Responses Laboratory, Prince of Wales Clinical Research Sciences, Sydney, NSW 2031, Australia.
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8
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Morimoto R, Yoshioka K, Nakayama M, Nagai E, Okuno Y, Nakashima A, Ogawa T, Suzuki K, Enomoto T, Isegawa Y. Juice of Citrullus lanatus var. citroides (wild watermelon) inhibits the entry and propagation of influenza viruses in vitro and in vivo. Food Sci Nutr 2021; 9:544-552. [PMID: 33473315 PMCID: PMC7802580 DOI: 10.1002/fsn3.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 10/27/2020] [Accepted: 11/02/2020] [Indexed: 12/30/2022] Open
Abstract
Vaccines and various anti-influenza drugs are clinically used to prevent and treat influenza infections. However, with the antigenic mismatch of vaccines and the emergence of drug-resistant viral strains, new approaches for treating influenza are warranted. This study focused on natural foods as potential candidates for the development of new treatment options for influenza infections. The screening of plants from the Cucurbitaceae family revealed that the juice of Citrullus lanatus var. citroides (wild watermelon) had the strongest ability to inhibit the replication of influenza virus in Madin-Darby canine kidney cells. The results of a time-of-addition assay indicated that wild watermelon juice (WWMJ) inhibits the adsorption and late stages of viral replication, suggesting that WWMJ contains multiple constituents with effective anti-influenza activity. A viral adsorption analysis showed that WWMJ reduces the amount of viral RNA in the cells at 37°C but not at 4°C, confirming that WWMJ inhibits viral entry into the host cells at 37°C. These results suggest that a mechanism other than the inhibition of viral attachment is involved in the anti-influenza action of WWMJ, which is perhaps responsible for a reduction in internalization of the virus. Administration of WWMJ into the nasal mucosa of BALB/c mice infected with the A/PR/8/34 mouse-adapted influenza virus was seen to significantly improve the survival rate. The findings of this study, therefore, demonstrate the anti-influenza potential of WWMJ in vitro and in vivo, thereby suggesting the candidature of WWMJ as a functional food product that can be used to develop anti-influenza agents and drugs.
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Affiliation(s)
- Ryosuke Morimoto
- Department of Food Sciences and NutritionSchool of Human Environmental SciencesMukogawa Women’s UniversityNishinomiyaJapan
- Faculty of Human Life ScienceShikoku University TokushimaTokushimaJapan
- Present address:
Faculty of Human Life ScienceShikoku University TokushimaTokushimaJapan
| | - Kae Yoshioka
- Department of Food Sciences and NutritionSchool of Human Environmental SciencesMukogawa Women’s UniversityNishinomiyaJapan
| | - Miyu Nakayama
- Department of Food Sciences and NutritionSchool of Human Environmental SciencesMukogawa Women’s UniversityNishinomiyaJapan
| | - Emiko Nagai
- Department of Food ScienceIshikawa Prefectural UniversityNonoichiJapan
| | | | | | | | | | - Toshiki Enomoto
- Department of Food ScienceIshikawa Prefectural UniversityNonoichiJapan
| | - Yuji Isegawa
- Department of Food Sciences and NutritionSchool of Human Environmental SciencesMukogawa Women’s UniversityNishinomiyaJapan
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Tian J, Qu N, Jiao X, Wang X, Geng J, Griffin N, Shan F. Methionine enkephalin inhibits influenza A virus infection through upregulating antiviral state in RAW264.7 cells. Int Immunopharmacol 2019; 78:106032. [PMID: 31835089 DOI: 10.1016/j.intimp.2019.106032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Revised: 11/04/2019] [Accepted: 11/05/2019] [Indexed: 01/27/2023]
Abstract
MENK, as an immune adjuvant, has potential immune-regulatory activity on innate and adaptive immune cells. The aim of this work was to investigate the antiviral effect of MENK on influenza virus-infected murine macrophage cells (RAW264.7) and its underlying mechanisms. The results showed that MENK markedly inhibited influenza A virus (H1N1) replication in pre- and post-MENK treatment, especially in pre-MENK treatment. The mechanisms exploration revealed that MENK (10 mg/mL) significantly inhibited the nucleoprotein (NP) of influenza virus and up-regulated levels of IL-6, TNF-α and IFN-β compared with those in H1N1 control group. Further experiments confirmed that antiviral effects of MENK was associated with promotion of opioid receptor (MOR) as well as activation of NF-κB p65 inducing cellular antiviral status. The data suggest that MENK should be potential candidate for prophylactic or therapeutic treatment against H1N1 influenza virus.
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Affiliation(s)
- Jing Tian
- Department of Immunology, School of Basic Medical Science, Jinzhou Medical University, Jinzhou 121001, China; Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Na Qu
- Department of Gynecology, Cancer Hospital, China Medical University, Shenyang 110042, China
| | - Xue Jiao
- Department of Translational Medicine, No.4 Teaching Hospital, China Medical University, Shenyang 110032, China
| | - Xiaonan Wang
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Jin Geng
- Department of Ophthalmology, No.1 Teaching Hospital, China Medical University, Shenyang 110001, China
| | - Noreen Griffin
- Immune Therapeutics, Inc., 37 North Orange Avenue, Suite 607, Orlando, FL 32801, USA
| | - Fengping Shan
- Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang 110122, China.
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10
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Ancestral and Compensatory Mutations that Promote Antiviral Resistance in Influenza N1 Neuraminidase Revealed by a Phylonumerics Approach. J Mol Evol 2018; 86:546-553. [DOI: 10.1007/s00239-018-9866-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/12/2018] [Indexed: 10/28/2022]
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11
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Rapid and simple detection of Tamiflu-resistant influenza virus: Development of oseltamivir derivative-based lateral flow biosensor for point-of-care (POC) diagnostics. Sci Rep 2018; 8:12999. [PMID: 30158601 PMCID: PMC6115449 DOI: 10.1038/s41598-018-31311-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 08/16/2018] [Indexed: 01/16/2023] Open
Abstract
We have developed a novel oseltamivir derivative (oseltamivir hexylthiol; OHT) that exhibits a higher binding affinity for Tamiflu-resistant virus (Tamiflu resistance) than for the wild-type virus (Tamiflu-susceptible virus; WT) as an antibody. First, OHT-modified gold nanoparticles (OHT-GNPs) are used in a simple colorimetric assay as nanoprobes for the Tamiflu-resistant virus. In the presence of Tamiflu-resistant virus, they show a colorimetric change from deep red to purple because of the OHT-GNP aggregation driven by strong interactions between OHT and neuraminidase (NA) on the surface of the Tamiflu-resistance. Moreover, the color gradually turns purple as the concentration of the Tamiflu-resistant virus increases, allowing the determination of the presence of the virus with the naked eye. Furthermore, an OHT-based lateral flow assay (LFA) has been developed as a rapid and easy detection device for Tamiflu resistance. It shows detection specificity for various virus concentrations of Tamiflu-resistant virus even for the mixture of WT and Tamiflu-resistant viruses, where the limit of detection (LOD) is 5 × 102 ~ 103 PFU per test (=1 × 104 PFU/mL). It has been confirmed that this platform can provide accurate information on whether a virus exhibits Tamiflu resistance, thus supporting the selection of appropriate treatments using point-of-care (POC) diagnostics.
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12
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Nachbagauer R, Shore D, Yang H, Johnson SK, Gabbard JD, Tompkins SM, Wrammert J, Wilson PC, Stevens J, Ahmed R, Krammer F, Ellebedy AH. Broadly Reactive Human Monoclonal Antibodies Elicited following Pandemic H1N1 Influenza Virus Exposure Protect Mice against Highly Pathogenic H5N1 Challenge. J Virol 2018; 92:e00949-18. [PMID: 29899095 PMCID: PMC6069173 DOI: 10.1128/jvi.00949-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 06/02/2018] [Indexed: 12/16/2022] Open
Abstract
Broadly cross-reactive antibodies (Abs) that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes, including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (MAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the MAbs bound HAs from multiple strains of group 1 viruses, and one MAb, 05-2G02, bound to both group 1 and group 2 influenza A virus HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two MAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One MAb, 70-1F02, cocrystallized with H5 HA and showed heavy-chain-only interactions similar to those seen with the previously described CR6261 anti-stalk antibody. Finally, we show that antibodies that compete with these MAbs are prevalent in serum from an individual recently infected with the A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections by zoonotic or emerging pandemic influenza viruses.IMPORTANCE The rise in zoonotic infections of humans by emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually worldwide. Currently available antiviral treatment options include only neuraminidase inhibitors, but some influenza viruses are naturally resistant to these drugs, and others quickly develop resistance-conferring mutations. Alternative therapeutics are urgently needed. Broadly protective antibodies that target the conserved "stalk" domain of the hemagglutinin represent potential potent antiviral prophylactic and therapeutic agents that can assist pandemic preparedness. Here, we describe four human monoclonal antibodies that target conserved regions of influenza HA and characterize their binding spectrum as well as their protective capacity in prophylactic and therapeutic settings against a lethal challenge with a zoonotic influenza virus.
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Affiliation(s)
- Raffael Nachbagauer
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - David Shore
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Hua Yang
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Scott K Johnson
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jon D Gabbard
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - S Mark Tompkins
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jens Wrammert
- Emory Vaccine Center, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Patrick C Wilson
- Department of Medicine, Section of Rheumatology, The Committee on Immunology, The Knapp Center for Lupus and Immunology Research, The University of Chicago, Chicago, Illinois, USA
| | - James Stevens
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Rafi Ahmed
- Emory Vaccine Center, School of Medicine, Emory University, Atlanta, Georgia, USA
- Department of Microbiology and Immunology, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Florian Krammer
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Ali H Ellebedy
- Emory Vaccine Center, School of Medicine, Emory University, Atlanta, Georgia, USA
- Department of Microbiology and Immunology, School of Medicine, Emory University, Atlanta, Georgia, USA
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13
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Kinetic, Thermodynamic, and Structural Analysis of Drug Resistance Mutations in Neuraminidase from the 2009 Pandemic Influenza Virus. Viruses 2018; 10:v10070339. [PMID: 29933553 PMCID: PMC6071225 DOI: 10.3390/v10070339] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/14/2018] [Accepted: 06/19/2018] [Indexed: 12/25/2022] Open
Abstract
Neuraminidase is the main target for current influenza drugs. Reduced susceptibility to oseltamivir, the most widely prescribed neuraminidase inhibitor, has been repeatedly reported. The resistance substitutions I223V and S247N, alone or in combination with the major oseltamivir-resistance mutation H275Y, have been observed in 2009 pandemic H1N1 viruses. We overexpressed and purified the ectodomain of wild-type neuraminidase from the A/California/07/2009 (H1N1) influenza virus, as well as variants containing H275Y, I223V, and S247N single mutations and H275Y/I223V and H275Y/S247N double mutations. We performed enzymological and thermodynamic analyses and structurally examined the resistance mechanism. Our results reveal that the I223V or S247N substitution alone confers only a moderate reduction in oseltamivir affinity. In contrast, the major oseltamivir resistance mutation H275Y causes a significant decrease in the enzyme’s ability to bind this drug. Combination of H275Y with an I223V or S247N mutation results in extreme impairment of oseltamivir’s inhibition potency. Our structural analyses revealed that the H275Y substitution has a major effect on the oseltamivir binding pose within the active site while the influence of other studied mutations is much less prominent. Our crystal structures also helped explain the augmenting effect on resistance of combining H275Y with both substitutions.
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14
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Hadházi Á, Li L, Bailly B, Maggioni A, Martin G, Dirr L, Dyason JC, Thomson RJ, Gao GF, Borbás A, Ve T, Pascolutti M, von Itzstein M. A Sulfonozanamivir Analogue Has Potent Anti-influenza Virus Activity. ChemMedChem 2018; 13:785-789. [DOI: 10.1002/cmdc.201800092] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Ádám Hadházi
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
- Department of Pharmaceutical Chemistry; University of Debrecen; 4032 Debrecen Hungary
| | - Linghui Li
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
- University of Chinese Academy of Sciences; Beijing 101408 China
| | - Benjamin Bailly
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Andrea Maggioni
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Gael Martin
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Larissa Dirr
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Jeffrey C. Dyason
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Robin J. Thomson
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - George F. Gao
- Savaid Medical School; University of Chinese Academy of Sciences; Beijing 101408 China
| | - Anikó Borbás
- Department of Pharmaceutical Chemistry; University of Debrecen; 4032 Debrecen Hungary
| | - Thomas Ve
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Mauro Pascolutti
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
| | - Mark von Itzstein
- Institute for Glycomics, Gold Coast Campus; Griffith University; Queensland 4222 Australia
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15
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Nagai E, Iwai M, Koketsu R, Sogabe R, Morimoto R, Suzuki Y, Ohta Y, Okuno Y, Ohshima A, Enomoto T, Isegawa Y. Inhibition of influenza virus replication by adlay tea. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:1899-1905. [PMID: 28902408 DOI: 10.1002/jsfa.8671] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 09/02/2017] [Accepted: 09/04/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND The present study was conducted aiming to examine the antiviral activity of adlay tea and its components against influenza viruses. We further aimed to clarify the mechanism by which these components regulate virus replication. RESULTS Adlay tea at a concentration suitable for drinking inhibited the multiplication of influenza viruses. Moreover, our results suggest that individual components of the tea had antiviral activities against the influenza A/PR/8/34 virus. Adlay tea inhibited multiplication of the H1N1, H3N2 and B types of influenza virus, including oseltamivir-resistant viruses. In addition, adlay tea inhibited influenza infection during the periods of virus adsorption to the cell and virus replication. Adlay tea did not suppress hemagglutination inhibition or cell fusion, although it slightly inhibited virus binding to Malin Darby canine kidney cells. Furthermore, our findings suggest that the antiviral compounds included in adlay tea were ingredients other than polyphenols and that there were several types of effective compounds in adlay tea inhibiting several steps of viral replication. CONCLUSION The results of the present study demonstrate that adlay tea had antiviral effects against influenza viruses. Our findings with respect to adlay tea suggest that the polyphenols might have a small influence on its antiviral activity and that other ingredients might have more influence. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Emiko Nagai
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
- Department of Food Science, Ishikawa Prefectural University, Nonoichi, Ishikawa, Japan
| | - Miwa Iwai
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | - Ritsuko Koketsu
- Research Foundation for Microbial Diseases of Osaka University, Suita, Osaka, Japan
| | - Riho Sogabe
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | - Ryosuke Morimoto
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | - Yuri Suzuki
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
| | | | - Yoshinobu Okuno
- Research Foundation for Microbial Diseases of Osaka University, Suita, Osaka, Japan
| | - Atsushi Ohshima
- Genomics Program, Nagahamabio Institute of Bio-Science and Technology, Nagahama, Shiga, Japan
| | - Toshiki Enomoto
- Department of Food Science, Ishikawa Prefectural University, Nonoichi, Ishikawa, Japan
| | - Yuji Isegawa
- Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan
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16
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Tian J, Jiao X, Wang X, Geng J, Wang R, Liu N, Gao X, Griffin N, Shan F. Novel effect of methionine enkephalin against influenza A virus infection through inhibiting TLR7-MyD88-TRAF6-NF-κB p65 signaling pathway. Int Immunopharmacol 2018; 55:38-48. [DOI: 10.1016/j.intimp.2017.12.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/29/2017] [Accepted: 12/01/2017] [Indexed: 02/07/2023]
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17
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Holthausen DJ, Lee SH, Kumar VTV, Bouvier NM, Krammer F, Ellebedy AH, Wrammert J, Lowen AC, George S, Pillai MR, Jacob J. An Amphibian Host Defense Peptide Is Virucidal for Human H1 Hemagglutinin-Bearing Influenza Viruses. Immunity 2017; 46:587-595. [DOI: 10.1016/j.immuni.2017.03.018] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 02/02/2017] [Accepted: 02/16/2017] [Indexed: 01/11/2023]
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18
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Resistance to Mutant Group 2 Influenza Virus Neuraminidases of an Oseltamivir-Zanamivir Hybrid Inhibitor. J Virol 2016; 90:10693-10700. [PMID: 27654293 DOI: 10.1128/jvi.01703-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 09/11/2016] [Indexed: 12/18/2022] Open
Abstract
Influenza virus neuraminidase (NA) drug resistance is one of the challenges to preparedness against epidemic and pandemic influenza virus infections. NA N1- and N2-containing influenza viruses are the primary cause of seasonal epidemics and past pandemics. The structural and functional basis underlying drug resistance of the influenza virus N1 NA is well characterized. Yet drug resistance of the N2 strain is not well understood. Here, we confirm that replacement of N2 E119 or I222 results in multidrug resistance, and when the replacements occur together, the sensitivity to NA inhibitors (NAI) is reduced severely. Using crystallographic studies, we showed that E119 replacement results in a loss of hydrogen bonding to oseltamivir and zanamivir, whereas I222 replacement results in a change in the hydrophobic environment that is critical for oseltamivir binding. Moreover, we found that MS-257, a zanamivir-oseltamivir hybrid inhibitor, is less susceptible to drug resistance. The binding mode of MS-257 shows that increased hydrogen bonding interactions between the inhibitor and NA active site anchor the inhibitor within the active site and allow adjustments in response to active-site modifications. Such stability is likely responsible for the observed reduced susceptibility to drug resistance. MS-257 serves as a next-generation anti-influenza virus drug candidate and serves also as a scaffold for further design of NAIs. IMPORTANCE Oseltamivir and zanamivir are the two major antiviral drugs available for the treatment of influenza virus infections. However, multidrug-resistant viruses have emerged in clinical cases, which pose a challenge for the development of new drugs. N1 and N2 subtypes exist in the viruses which cause seasonal epidemics and past pandemics. Although N1 drug resistance is well characterized, the molecular mechanisms underlying N2 drug resistance are unknown. A previous report showed that an N2 E119V/I222L dual mutant conferred drug resistance to seasonal influenza virus. Here, we confirm that these substitutions result in multidrug resistance and dramatically reduced sensitivity to NAI. We further elucidate the molecular mechanism underlying N2 drug resistance by solving crystal structures of the N2 E119V and I222L mutants and the dual mutant. Most importantly, we found that a novel oseltamivir-zanamivir hybrid inhibitor, MS-257, remains more effective against drug-resistant N2 and is a promising candidate as a next-generation anti-influenza virus drug.
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Design and synthesis of 1,2,3-triazole-containing N-acyl zanamivir analogs as potent neuraminidase inhibitors. Eur J Med Chem 2016; 123:397-406. [PMID: 27487569 DOI: 10.1016/j.ejmech.2016.07.064] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 12/17/2022]
Abstract
The design of potent metabolically stable neuraminidase (NA) inhibitors represents an attractive approach for treating influenza virus infection. In this study, we describe the exploitation of the 150-cavity in the active site of group 1 NA for the design, synthesis, and in vitro evaluation of new triazole-containing N-acyl derivatives related to Zanamivir. Inhibition studies with influenza virus NAs of group 1 (H1N1) and group 2 (H3N2) revealed that several of them are good inhibitors, with IC50 values in the low nanomolar (2.3 nM-31 nM) range. Substituents that form stable van der Waals interaction with the 150-cavity residues play crucial roles in NA inhibition as demonstrated by the potency of 6a (H1N1 IC50 = 2.3 nM, and H3N2 IC50 = 2.9 nM). Docking studies indicated that the cyclohexane-substituted triazole ring extended toward the hydrophobic region in the active site of group 1 NA in open form. The high potency observed for inhibitor 6a may be attributable to the highly favorable hydrophobic interactions in this region.
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20
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Zhang H, Han Q, Ping X, Li L, Chang C, Chen Z, Shu Y, Xu K, Sun B. A single NS2 mutation of K86R promotes PR8 vaccine donor virus growth in Vero cells. Virology 2015; 482:32-40. [PMID: 25817403 DOI: 10.1016/j.virol.2015.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 12/30/2014] [Accepted: 03/02/2015] [Indexed: 02/05/2023]
Abstract
Vaccination is the most effective way to prevent and control infection by influenza viruses, and a cell-culture-based vaccine production system is preferred as the future choice for the large-scale production of influenza vaccines. As one of the WHO-recommended cell lines for producing influenza vaccines, Vero cells do not efficiently support the growth of the current influenza A virus vaccine donor strain, the A/Puerto Rico/8/1934 (PR8) virus. In this study, a single mutation of K86R in the NS2 protein can sufficiently render the high-yielding property to the PR8 virus in Vero cells. Further analysis showed that the later steps in the virus replication cycle were accelerated by NS2(K86R) mutation, which may relate to an enhanced interaction between NS2(K86R) and the components of host factor F1Fo-ATPase, FoB and F1β. Because the NS2(K86R) mutation does not increase PR8 virulence in either mice or embryonated eggs, the PR8-NS2(K86R) virus could serve as a promising vaccine donor strain in Vero cells.
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Affiliation(s)
- Hong Zhang
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China
| | - Qinglin Han
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China
| | - Xianqiang Ping
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China; Shanghai Normal University, No. 100 Guilin Road, Shanghai 200234, China
| | - Li Li
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China
| | - Chong Chang
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China
| | - Ze Chen
- Shanghai Institute of Biological Products, Shanghai 200052, China
| | - Yuelong Shu
- Chinese Center for Disease Control and Prevention, Yingxin Street 100, Xuanwu District, Beijing 100052, China
| | - Ke Xu
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China.
| | - Bing Sun
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China; State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 YueYang Road, Shanghai 200031, China.
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21
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Hai R, Schmolke M, Leyva-Grado VH, Thangavel RR, Margine I, Jaffe EL, Krammer F, Solórzano A, García-Sastre A, Palese P, Bouvier NM. Influenza A(H7N9) virus gains neuraminidase inhibitor resistance without loss of in vivo virulence or transmissibility. Nat Commun 2014; 4:2854. [PMID: 24326875 PMCID: PMC3863970 DOI: 10.1038/ncomms3854] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Accepted: 11/01/2013] [Indexed: 12/17/2022] Open
Abstract
Without baseline human immunity to the emergent avian influenza A(H7N9) virus, neuraminidase inhibitors are vital for controlling viral replication in severe infections. An amino acid change in the viral neuraminidase associated with drug resistance, NA-R292K (N2 numbering), has been found in some H7N9 clinical isolates. Here we assess the impact of the NA-R292K substitution on antiviral sensitivity and viral replication, pathogenicity and transmissibility of H7N9 viruses. Our data indicate that an H7N9 isolate encoding the NA-R292K substitution is highly resistant to oseltamivir and peramivir and partially resistant to zanamivir. Furthermore, H7N9 reassortants with and without the resistance mutation demonstrate comparable viral replication in primary human respiratory cells, virulence in mice and transmissibility in guinea pigs. Thus, in stark contrast to oseltamivir-resistant seasonal influenza A(H3N2) viruses, H7N9 virus replication and pathogenicity in these models are not substantially altered by the acquisition of high-level oseltamivir resistance due to the NA-R292K mutation. Some clinical isolates of influenza A(H7N9) virus encode a mutation within neuraminidase that could confer resistance to the only class of drugs active against H7N9. Here, the authors show that this mutation does not affect viral replication and pathogenicity while mediating resistance to antivirals in vivo.
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Affiliation(s)
- Rong Hai
- 1] Department of Microbiology, Icahn School of Medicine at Mount Sinai, One Gustave L Levy Place, Box 1124, New York, New York 10029, USA [2]
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22
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Yu B, Dai CQ, Jiang ZY, Li EQ, Chen C, Wu XL, Chen J, Liu Q, Zhao CL, He JX, Ju DH, Chen XY. Andrographolide as an anti-H1N1 drug and the mechanism related to retinoic acid-inducible gene-I-like receptors signaling pathway. Chin J Integr Med 2014; 20:540-5. [PMID: 24972581 DOI: 10.1007/s11655-014-1860-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To observe the anti-virus effects of andrographolide (AD) on the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) signaling pathway when immunological cells were infected with H1N1. METHODS Leukomonocyte was obtained from umbilical cord blood by Ficoll density gradient centrifugation, and immunological cells were harvested after cytokines stimulation. Virus infected cell model was established by H1N1 co-cultured with normal human bronchial epithelial cell line (16HBE). The optimal concentration of AD was defined by methyl-thiazolyl-tetrazolium (MTT) assay. After the virus infected cell model was established, AD was added into the medium as a treatment intervention. After 24-h co-culture, cell supernatant was collected for interferon gamma (IFN-γ) and interleukin-4 (IL-4) enzyme-linked immunosorbent assay (ELISA) detection while immunological cells for real-time polymerase chain reaction (RT-PCR). RESULTS The optimal concentration of AD for anti-virus effect was 250 μg/mL. IL-4 and IFN-γ in the supernatant and mRNA levels in RLRs pathway increased when cells was infected by virus, RIG-I, IFN-β promoter stimulator-1 (IPS-1), interferon regulatory factor (IRF)-7, IRF-3 and nuclear transcription factor κB (NF-κB) mRNA levels increased significantly (P<0.05). When AD was added into co-culture medium, the levels of IL-4 and IFN-γ were lower than those in the non-interference groups and the mRNA expression levels decreased, RIG-I, IPS-1, IRF-7, IRF-3 and NF-κB decreased significantly in each group with significant statistic differences (P<0.05). CONCLUSIONS The RLRs mediated viral recognition provided a potential molecular target for acute viral infections and andrographolide could ameliorate H1N1 virus-induced cell mortality. And the antiviral effects might be related to its inhibition of viral-induced activation of the RLRs signaling pathway.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Antiviral Agents/pharmacology
- Cells, Cultured
- Coculture Techniques
- DEAD Box Protein 58
- DEAD-box RNA Helicases/genetics
- DEAD-box RNA Helicases/metabolism
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Dendritic Cells/virology
- Diterpenes/pharmacology
- Fetal Blood/cytology
- Humans
- Influenza A Virus, H1N1 Subtype/drug effects
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza, Human/drug therapy
- Influenza, Human/immunology
- Influenza, Human/virology
- Interferon-beta/genetics
- Interferon-beta/metabolism
- Interferon-gamma/metabolism
- Interleukin-4/metabolism
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/virology
- Macrophages/drug effects
- Macrophages/virology
- NF-kappa B/genetics
- NF-kappa B/metabolism
- Promoter Regions, Genetic/drug effects
- Promoter Regions, Genetic/immunology
- RNA, Messenger/metabolism
- Receptors, Immunologic
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Signal Transduction/immunology
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Affiliation(s)
- Bin Yu
- Department of Traditional Chinese Medicine, School of Medicine, Jinan University, Guangzhou, 510632, China
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23
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Yang YJ, Li JY, Liu XW, Zhang JY, Liu YR, Li B. A non-biological method for screening active components against influenza virus from traditional Chinese medicine by coupling a LC column with oseltamivir molecularly imprinted polymers. PLoS One 2013; 8:e84458. [PMID: 24386385 PMCID: PMC3873415 DOI: 10.1371/journal.pone.0084458] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 11/22/2013] [Indexed: 12/22/2022] Open
Abstract
To develop a non-biological method for screening active components against influenza virus from traditional Chinese medicine (TCM) extraction, a liquid chromatography (LC) column prepared with oseltamivir molecularly imprinted polymer (OSMIP) was employed with LC-mass spectrometry (LC-MS). From chloroform extracts of compound TCM liquid preparation, we observed an affinitive component m/z 249, which was identified to be matrine following analysis of phytochemical literatures, OSMIP-LC column on-line of control compounds and MS/MS off-line. The results showed that matrine had similar bioactivities with OS against avian influenza virus H9N2 in vitro for both alleviating cytopathic effect and hemagglutination inhibition and that the stereostructures of these two compounds are similar while their two-dimensional structures were different. In addition, our results suggested that the bioactivities of those affinitive compounds were correlated with their chromatographic behaviors, in which less difference of the chromatographic behaviors might have more similar bioactivities. This indicates that matrine is a potential candidate drug to prevent or cure influenza for human or animal. In conclusion, the present study showed that molecularly imprinted polymers can be used as a non-biological method for screening active components against influenza virus from TCM.
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Affiliation(s)
- Ya-Jun Yang
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
| | - Jian-Yong Li
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
- * E-mail:
| | - Xi-Wang Liu
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
| | - Ji-Yu Zhang
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
| | - Yu-Rong Liu
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
| | - Bing Li
- Gansu Provincial Engineering Research Center for New Animal Drug, Key Laboratory of New Animal Drug Project, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou, Gansu Province, China
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24
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Souza TML, Resende PC, Fintelman-Rodrigues N, Gregianini TS, Ikuta N, Fernandes SB, Cury ALF, Rosa MDCD, Siqueira MM. Detection of oseltamivir-resistant pandemic influenza A(H1N1)pdm2009 in Brazil: can community transmission be ruled out? PLoS One 2013; 8:e80081. [PMID: 24244615 PMCID: PMC3823798 DOI: 10.1371/journal.pone.0080081] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 10/09/2013] [Indexed: 12/22/2022] Open
Abstract
Although surveillance efforts that monitor the emergence of drug-resistant strains of influenza are critical, systematic analysis is overlooked in most developing countries. We report on the occurrence of strains of pandemic influenza A(H1N1)pdm09 with resistance and decreased susceptibility to oseltamivir (OST) in Brazil in 2009, 2011 and 2012. We found 7 mutant viruses, 2 with the mutation S247N and other 5 with the mutation H275Y. Most of these viruses were from samples concentrated in the southern region of Brazil. Some of these resistant viruses were detected prior to the initiation of OST treatment, suggesting that community transmission of mutant viruses may exist. Moreover, we show that one of these OST-resistant (H275Y) strains of A(H1N1)pdm09 was discovered in the tri-border region between Brazil, Argentina and Paraguay, highlighting that this strain could also be found in other Latin American countries. Our findings reinforce the importance of enhanced antiviral resistance surveillance in Brazil and in other Latin American countries to confirm or rule out the community transmission of OST-resistant strains of A(H1N1)pdm09.
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MESH Headings
- Adolescent
- Adult
- Aged
- Animals
- Antiviral Agents/therapeutic use
- Brazil/epidemiology
- Child
- Child, Preschool
- Dogs
- Drug Resistance, Viral/drug effects
- Drug Resistance, Viral/genetics
- Epidemiological Monitoring
- Humans
- Infant
- Infant, Newborn
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/isolation & purification
- Influenza, Human/drug therapy
- Influenza, Human/epidemiology
- Influenza, Human/transmission
- Influenza, Human/virology
- Madin Darby Canine Kidney Cells
- Middle Aged
- Mutation
- Neuraminidase/antagonists & inhibitors
- Neuraminidase/genetics
- Oseltamivir/therapeutic use
- Viral Proteins/antagonists & inhibitors
- Viral Proteins/genetics
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Affiliation(s)
- Thiago Moreno L. Souza
- Laboratório de Vírus Respiratórios e do Sarampo, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
| | - Paola C. Resende
- Laboratório de Vírus Respiratórios e do Sarampo, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Natalia Fintelman-Rodrigues
- Laboratório de Vírus Respiratórios e do Sarampo, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tatiana Schaffer Gregianini
- Laboratório Central de Saúde Pública do Estado do Rio de Grande do Sul, Fundação Estadual de Produção e Pesquisa em Saúde Seção de Virologia, Porto Alegre, Rio Grando do Sul, Brazil
| | - Nilo Ikuta
- Universidade Luterana do Brasil, Porto Alegre, Rio Grande do Sul, Brazil
| | | | - Ana Luisa Furtado Cury
- Laboratório Central de Saúde Pública do Estado de Minas Gerais, Instituto Octávio Magalhães Fundação Ezequiel Dias, Belo Horizonte, Minas Gerais, Brazil
| | | | - Marilda M. Siqueira
- Laboratório de Vírus Respiratórios e do Sarampo, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
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25
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Adabala PJP, LeGresley EB, Bance N, Niikura M, Pinto BM. Exploitation of the Catalytic Site and 150 Cavity for Design of Influenza A Neuraminidase Inhibitors. J Org Chem 2013; 78:10867-77. [DOI: 10.1021/jo401854w] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Pal John Pal Adabala
- Department
of Chemistry and ‡Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - Eric B. LeGresley
- Department
of Chemistry and ‡Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - Nicole Bance
- Department
of Chemistry and ‡Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - Masahiro Niikura
- Department
of Chemistry and ‡Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - B. Mario Pinto
- Department
of Chemistry and ‡Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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26
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Govorkova EA. Consequences of resistance: in vitro fitness, in vivo infectivity, and transmissibility of oseltamivir-resistant influenza A viruses. Influenza Other Respir Viruses 2013; 7 Suppl 1:50-7. [PMID: 23279897 DOI: 10.1111/irv.12044] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The development of drug resistance is a major drawback to any antiviral therapy, and the specific anti-influenza drugs, the neuraminidase (NA) inhibitors (NAIs), are not excluded from this rule. The impact of drug resistance depends on the degree of reduction in fitness of the particular drug-resistant virus. If the resistance mutations lead to only a modest biological fitness cost and the virus remains highly transmissible, the effectiveness of antiviral use is likely to be reduced. This review focuses on the fitness of oseltamivir-resistant seasonal H1N1 and H3N2, 2009 pandemic H1N1 (H1N1pdm09), and highly pathogenic H5N1 influenza A viruses carrying clinically derived NAI resistance-associated NA mutations.
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Affiliation(s)
- Elena A Govorkova
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-2794, USA.
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27
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Recombinant IgA is sufficient to prevent influenza virus transmission in guinea pigs. J Virol 2013; 87:7793-804. [PMID: 23698296 DOI: 10.1128/jvi.00979-13] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A serum hemagglutination inhibition (HAI) titer of 40 or greater is thought to be associated with reduced influenza virus pathogenesis in humans and is often used as a correlate of protection in influenza vaccine studies. We have previously demonstrated that intramuscular vaccination of guinea pigs with inactivated influenza virus generates HAI titers greater than 300 but does not protect vaccinated animals from becoming infected with influenza virus by transmission from an infected cage mate. Only guinea pigs intranasally inoculated with a live influenza virus or a live attenuated virus vaccine, prior to challenge, were protected from transmission (A. C. Lowen et al., J. Virol. 83:2803-2818, 2009.). Because the serum HAI titer is mostly determined by IgG content, these results led us to speculate that prevention of viral transmission may require IgA antibodies or cellular immune responses. To evaluate this hypothesis, guinea pigs and ferrets were administered a potent, neutralizing mouse IgG monoclonal antibody, 30D1 (Ms 30D1 IgG), against the A/California/04/2009 (H1N1) virus hemagglutinin and exposed to respiratory droplets from animals infected with this virus. Even though HAI titers were greater than 160 1 day postadministration, Ms 30D1 IgG did not prevent airborne transmission to passively immunized recipient animals. In contrast, intramuscular administration of recombinant 30D1 IgA (Ms 30D1 IgA) prevented transmission to 88% of recipient guinea pigs, and Ms 30D1 IgA was detected in animal nasal washes. Ms 30D1 IgG administered intranasally also prevented transmission, suggesting the importance of mucosal immunity in preventing influenza virus transmission. Collectively, our data indicate that IgG antibodies may prevent pathogenesis associated with influenza virus infection but do not protect from virus infection by airborne transmission, while IgA antibodies are more important for preventing transmission of influenza viruses.
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28
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van der Vries E, Collins PJ, Vachieri SG, Xiong X, Liu J, Walker PA, Haire LF, Hay AJ, Schutten M, Osterhaus ADME, Martin SR, Boucher CAB, Skehel JJ, Gamblin SJ. H1N1 2009 pandemic influenza virus: resistance of the I223R neuraminidase mutant explained by kinetic and structural analysis. PLoS Pathog 2012; 8:e1002914. [PMID: 23028314 PMCID: PMC3447749 DOI: 10.1371/journal.ppat.1002914] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 08/05/2012] [Indexed: 12/16/2022] Open
Abstract
Two classes of antiviral drugs, neuraminidase inhibitors and adamantanes, are approved for prophylaxis and therapy against influenza virus infections. A major concern is that antiviral resistant viruses emerge and spread in the human population. The 2009 pandemic H1N1 virus is already resistant to adamantanes. Recently, a novel neuraminidase inhibitor resistance mutation I223R was identified in the neuraminidase of this subtype. To understand the resistance mechanism of this mutation, the enzymatic properties of the I223R mutant, together with the most frequently observed resistance mutation, H275Y, and the double mutant I223R/H275Y were compared. Relative to wild type, K(M) values for MUNANA increased only 2-fold for the single I223R mutant and up to 8-fold for the double mutant. Oseltamivir inhibition constants (K(I)) increased 48-fold in the single I223R mutant and 7500-fold in the double mutant. In both cases the change was largely accounted for by an increased dissociation rate constant for oseltamivir, but the inhibition constants for zanamivir were less increased. We have used X-ray crystallography to better understand the effect of mutation I223R on drug binding. We find that there is shrinkage of a hydrophobic pocket in the active site as a result of the I223R change. Furthermore, R223 interacts with S247 which changes the rotamer it adopts and, consequently, binding of the pentoxyl substituent of oseltamivir is not as favorable as in the wild type. However, the polar glycerol substituent present in zanamivir, which mimics the natural substrate, is accommodated in the I223R mutant structure in a similar way to wild type, thus explaining the kinetic data. Our structural data also show that, in contrast to a recently reported structure, the active site of 2009 pandemic neuraminidase can adopt an open conformation.
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Affiliation(s)
| | - Patrick J. Collins
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Sebastien G. Vachieri
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Xiaoli Xiong
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Junfeng Liu
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
- MOA Key Laboratory of Plant Pathology, China Agricultural University, Beijing, People's Republic of China
| | - Philip A. Walker
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Lesley F. Haire
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Alan J. Hay
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Martin Schutten
- Erasmus Medical Centre, Department of Virology, Rotterdam, The Netherlands
| | | | - Steve R. Martin
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | | | - John J. Skehel
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
- * E-mail:
| | - Steve J. Gamblin
- Medical Research Council, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
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29
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The H275Y neuraminidase mutation of the pandemic A/H1N1 influenza virus lengthens the eclipse phase and reduces viral output of infected cells, potentially compromising fitness in ferrets. J Virol 2012; 86:10651-60. [PMID: 22837199 DOI: 10.1128/jvi.07244-11] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The H275Y amino acid substitution of the neuraminidase gene is the most common mutation conferring oseltamivir resistance in the N1 subtype of the influenza virus. Using a mathematical model to analyze a set of in vitro experiments that allow for the full characterization of the viral replication cycle, we show that the primary effects of the H275Y substitution on the pandemic H1N1 (H1N1pdm09) strain are to lengthen the mean eclipse phase of infected cells (from 6.6 to 9.1 h) and decrease (by 7-fold) the viral burst size, i.e., the total number of virions produced per cell. We also find, however, that the infectious-unit-to-particle ratio of the H275Y mutant strain is 12-fold higher than that of the oseltamivir-susceptible strain (0.19 versus 0.016 per RNA copy). A parallel analysis of the H275Y mutation in the prior seasonal A/Brisbane/59/2007 background shows similar changes in the infection kinetic parameters, but in this background, the H275Y mutation also allows the mutant to infect cells five times more rapidly. Competitive mixed-strain infections in vitro, where the susceptible and resistant H1N1pdm09 strains must compete for cells, are characterized by higher viral production by the susceptible strain but suggest equivalent fractions of infected cells in the culture. In ferrets, however, the mutant strain appears to suffer a delay in its infection of the respiratory tract that allows the susceptible strain to dominate mixed-strain infections.
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30
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Enhanced mammalian transmissibility of seasonal influenza A/H1N1 viruses encoding an oseltamivir-resistant neuraminidase. J Virol 2012; 86:7268-79. [PMID: 22532693 DOI: 10.1128/jvi.07242-12] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Between 2007 and 2009, oseltamivir resistance developed among seasonal influenza A/H1N1 (sH1N1) virus isolates at an exponential rate, without a corresponding increase in oseltamivir usage. We hypothesized that the oseltamivir-resistant neuraminidase (NA), in addition to being relatively insusceptible to the antiviral effect of oseltamivir, might confer an additional fitness advantage on these viruses by enhancing their transmission efficiency among humans. Here we demonstrate that an oseltamivir-resistant clinical isolate, an A/Brisbane/59/2007(H1N1)-like virus isolated in New York State in 2008, transmits more efficiently among guinea pigs than does a highly similar, contemporaneous oseltamivir-sensitive isolate. With reverse genetics reassortants and point mutants of the two clinical isolates, we further show that expression of the oseltamivir-resistant NA in the context of viral proteins from the oseltamivir-sensitive virus (a 7:1 reassortant) is sufficient to enhance transmissibility. In the guinea pig model, the NA is the critical determinant of transmission efficiency between oseltamivir-sensitive and -resistant Brisbane/59-like sH1N1 viruses, independent of concurrent drift mutations that occurred in other gene products. Our data suggest that the oseltamivir-resistant NA (specifically, one or both of the companion mutations, H275Y and D354G) may have allowed resistant Brisbane/59-like viruses to outtransmit sensitive isolates. These data provide in vivo evidence of an evolutionary mechanism that would explain the rapidity with which oseltamivir resistance achieved fixation among sH1N1 isolates in the human reservoir.
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