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Sun M, Manson ML, Guo T, de Lange ECM. CNS Viral Infections-What to Consider for Improving Drug Treatment: A Plea for Using Mathematical Modeling Approaches. CNS Drugs 2024; 38:349-373. [PMID: 38580795 PMCID: PMC11026214 DOI: 10.1007/s40263-024-01082-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/10/2024] [Indexed: 04/07/2024]
Abstract
Neurotropic viruses may cause meningitis, myelitis, encephalitis, or meningoencephalitis. These inflammatory conditions of the central nervous system (CNS) may have serious and devastating consequences if not treated adequately. In this review, we first summarize how neurotropic viruses can enter the CNS by (1) crossing the blood-brain barrier or blood-cerebrospinal fluid barrier; (2) invading the nose via the olfactory route; or (3) invading the peripheral nervous system. Neurotropic viruses may then enter the intracellular space of brain cells via endocytosis and/or membrane fusion. Antiviral drugs are currently used for different viral CNS infections, even though their use and dosing regimens within the CNS, with the exception of acyclovir, are minimally supported by clinical evidence. We therefore provide considerations to optimize drug treatment(s) for these neurotropic viruses. Antiviral drugs should cross the blood-brain barrier/blood cerebrospinal fluid barrier and pass the brain cellular membrane to inhibit these viruses inside the brain cells. Some antiviral drugs may also require intracellular conversion into their active metabolite(s). This illustrates the need to better understand these mechanisms because these processes dictate drug exposure within the CNS that ultimately determine the success of antiviral drugs for CNS infections. Finally, we discuss mathematical model-based approaches for optimizing antiviral treatments. Thereby emphasizing the potential of CNS physiologically based pharmacokinetic models because direct measurement of brain intracellular exposure in living humans faces ethical restrictions. Existing physiologically based pharmacokinetic models combined with in vitro pharmacokinetic/pharmacodynamic information can be used to predict drug exposure and evaluate efficacy of antiviral drugs within the CNS, to ultimately optimize the treatments of CNS viral infections.
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Affiliation(s)
- Ming Sun
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Martijn L Manson
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Tingjie Guo
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Elizabeth C M de Lange
- Division of Systems Pharmacology and Pharmacy, Leiden Academic Center for Drug Research, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
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Krasnov VP, Andronova VL, Belyavsky AV, Borisevich SS, Galegov GA, Kandarakov OF, Gruzdev DA, Vozdvizhenskaya OA, Levit GL. Large Subunit of the Human Herpes Simplex Virus Terminase as a Promising Target in Design of Anti-Herpesvirus Agents. Molecules 2023; 28:7375. [PMID: 37959793 PMCID: PMC10649544 DOI: 10.3390/molecules28217375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/19/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
Herpes simplex virus type 1 (HSV-1) is an extremely widespread pathogen characterized by recurrent infections. HSV-1 most commonly causes painful blisters or sores around the mouth or on the genitals, but it can also cause keratitis or, rarely, encephalitis. First-line and second-line antiviral drugs used to treat HSV infections, acyclovir and related compounds, as well as foscarnet and cidofovir, selectively inhibit herpesvirus DNA polymerase (DNA-pol). It has been previously found that (S)-4-[6-(purin-6-yl)aminohexanoyl]-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine (compound 1) exhibits selective anti-herpesvirus activity against HSV-1 in cell culture, including acyclovir-resistant mutants, so we consider it as a lead compound. In this work, the selection of HSV-1 clones resistant to the lead compound was carried out. High-throughput sequencing of resistant clones and reference HSV-1/L2 parent strain was performed to identify the genetic determinants of the virus's resistance to the lead compound. We identified a candidate mutation presumably associated with resistance to the virus, namely the T321I mutation in the UL15 gene encoding the large terminase subunit. Molecular modeling was used to evaluate the affinity and dynamics of the lead compound binding to the putative terminase binding site. The results obtained suggest that the lead compound, by binding to pUL15, affects the terminase complex. pUL15, which is directly involved in the processing and packaging of viral DNA, is one of the crucial components of the HSV terminase complex. The loss of its functional activity leads to disruption of the formation of mature virions, so it represents a promising drug target. The discovery of anti-herpesvirus agents that affect biotargets other than DNA polymerase will expand our possibilities of targeting HSV infections, including those resistant to baseline drugs.
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Affiliation(s)
- Victor P. Krasnov
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Valeriya L. Andronova
- Gamaleya National Research Center for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, Moscow 123098, Russia; (V.L.A.); (G.A.G.)
| | - Alexander V. Belyavsky
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia; (A.V.B.); (O.F.K.)
| | | | - George A. Galegov
- Gamaleya National Research Center for Epidemiology and Microbiology, Ministry of Health of the Russian Federation, Moscow 123098, Russia; (V.L.A.); (G.A.G.)
| | - Oleg F. Kandarakov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia; (A.V.B.); (O.F.K.)
| | - Dmitry A. Gruzdev
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Olga A. Vozdvizhenskaya
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
| | - Galina L. Levit
- Postovsky Institute of Organic Synthesis, Russian Academy of Sciences (Ural Branch), Ekaterinburg 620108, Russia; (D.A.G.); (O.A.V.); (G.L.L.)
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Sharma D, Sharma S, Akojwar N, Dondulkar A, Yenorkar N, Pandita D, Prasad SK, Dhobi M. An Insight into Current Treatment Strategies, Their Limitations, and Ongoing Developments in Vaccine Technologies against Herpes Simplex Infections. Vaccines (Basel) 2023; 11:vaccines11020206. [PMID: 36851084 PMCID: PMC9966607 DOI: 10.3390/vaccines11020206] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/05/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Herpes simplex virus (HSV) infection, the most prevalent viral infection that typically lasts for a lifetime, is associated with frequent outbreaks of oral and genital lesions. Oral herpes infection is mainly associated with HSV-1 through oral contact, while genital herpes originates due to HSV-2 and is categorized under sexually transmitted diseases. Immunocompromised patients and children are more prone to HSV infection. Over the years, various attempts have been made to find potential targets for the prevention of HSV infection. Despite the global distress caused by HSV infections, there are no licensed prophylactic and therapeutic vaccines available on the market against HSV. Nevertheless, there are numerous promising candidates in the pre-clinical and clinical stages of study. The present review gives an overview of two herpes viruses, their history, and life cycle, and different treatments adopted presently against HSV infections and their associated limitations. Majorly, the review covers the recent investigations being carried out globally regarding various vaccine strategies against oral and genital herpes virus infections, together with the recent and advanced nanotechnological approaches for vaccine development. Consequently, it gives an insight to researchers as well as people from the health sector about the challenges and upcoming solutions associated with treatment and vaccine development against HSV infections.
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Affiliation(s)
- Divya Sharma
- School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, Sector-III, Pushp Vihar, Government of NCT of Delhi, New Delhi 110017, India
| | - Supriya Sharma
- School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, Sector-III, Pushp Vihar, Government of NCT of Delhi, New Delhi 110017, India
| | - Natasha Akojwar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
| | - Ayusha Dondulkar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
| | - Nikhil Yenorkar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
| | - Deepti Pandita
- Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Sector-III, Pushp Vihar, Government of NCT of Delhi, New Delhi 110017, India
- Correspondence: (D.P.); (S.K.P.); (M.D.)
| | - Satyendra K. Prasad
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
- Correspondence: (D.P.); (S.K.P.); (M.D.)
| | - Mahaveer Dhobi
- School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, Sector-III, Pushp Vihar, Government of NCT of Delhi, New Delhi 110017, India
- Correspondence: (D.P.); (S.K.P.); (M.D.)
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4
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Acyclovir resistance in herpes simplex viruses: Prevalence and therapeutic alternatives. Biochem Pharmacol 2022; 206:115322. [DOI: 10.1016/j.bcp.2022.115322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 11/19/2022]
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Krishnan R, Stuart PM. Developments in Vaccination for Herpes Simplex Virus. Front Microbiol 2021; 12:798927. [PMID: 34950127 PMCID: PMC8691362 DOI: 10.3389/fmicb.2021.798927] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/12/2021] [Indexed: 11/13/2022] Open
Abstract
Herpes simplex virus (HSV) is an alpha herpes virus, with two subtypes: HSV-1 and HSV-2. HSV is one of the most prevalent sexually transmitted infections. It is the cause of severe neonatal infections and a leading cause of infectious blindness in the Western world. As of 2016, 13.2% of the global population ages 15-49 were existing with HSV-2 infection and 66.6% with HSV-1. This high prevalence of disease and the fact that resistance to current therapies is on the rise makes it imperative to develop and discover new methods of HSV prevention and management. Among the arsenal of therapies/treatments for this virus has been the development of a prophylactic or therapeutic vaccine to prevent the complications of HSV reactivation. Our current understanding of the immune responses involved in latency and reactivation provides a unique challenge to the development of vaccines. There are no approved vaccines currently available for either prophylaxis or therapy. However, there are various promising candidates in the pre-clinical and clinical phases of study. Vaccines are being developed with two broad focuses: preventative and therapeutic, some with a dual use as both immunotherapeutic and prophylactic. Within this article, we will review the current guidelines for the treatment of herpes simplex infections, our understanding of the immunological pathways involved, and novel vaccine candidates in development.
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Affiliation(s)
| | - Patrick M. Stuart
- Department of Ophthalmology, Saint Louis University School of Medicine, St. Louis, MO, United States
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Stojković D, Kostić M, Smiljković M, Aleksić M, Vasiljević P, Nikolić M, Soković M. Linking Antimicrobial Potential of Natural Products Derived from Aquatic Organisms and Microbes Involved in Alzheimer's Disease - A Review. Curr Med Chem 2020. [PMID: 29521212 DOI: 10.2174/0929867325666180309103645] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The following review is oriented towards microbes linked to Alzheimer's disease (AD) and antimicrobial effect of compounds and extracts derived from aquatic organisms against specific bacteria, fungi and viruses which were found previously in patients suffering from AD. Major group of microbes linked to AD include bacteria: Chlamydia pneumoniae, Helicobacter pylori, Porphyromonas gingivalis, Fusobacterium nucleatum, Prevotella intermedia, Actinomyces naeslundii, spirochete group; fungi: Candida sp., Cryptococcus sp., Saccharomyces sp., Malassezia sp., Botrytis sp., and viruses: herpes simplex virus type 1 (HSV-1), Human cytomegalovirus (CMV), hepatitis C virus (HCV). In the light of that fact, this review is the first to link antimicrobial potential of aquatic organisms against these sorts of microbes. This literature review might serve as a starting platform to develop novel supportive therapy for patients suffering from AD and to possibly prevent escalation of the disease in patients already having high-risk factors for AD occurrence.
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Affiliation(s)
- Dejan Stojković
- Department of Plant Physiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Serbia
| | - Marina Kostić
- Department of Plant Physiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Serbia
| | - Marija Smiljković
- Department of Plant Physiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Serbia
| | - Milena Aleksić
- Department of Biology and Ecology, Faculty of Science and Mathematics, University of Nis, Visegradska 33, 18000 Nis, Serbia
| | - Perica Vasiljević
- Department of Biology and Ecology, Faculty of Science and Mathematics, University of Nis, Visegradska 33, 18000 Nis, Serbia
| | - Miloš Nikolić
- Department of Plant Physiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Serbia
| | - Marina Soković
- Department of Plant Physiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Bulevar Despota Stefana 142, 11000 Belgrade, Serbia
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Álvarez DM, Castillo E, Duarte LF, Arriagada J, Corrales N, Farías MA, Henríquez A, Agurto-Muñoz C, González PA. Current Antivirals and Novel Botanical Molecules Interfering With Herpes Simplex Virus Infection. Front Microbiol 2020; 11:139. [PMID: 32117158 PMCID: PMC7026011 DOI: 10.3389/fmicb.2020.00139] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 01/21/2020] [Indexed: 12/31/2022] Open
Abstract
Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent within the human population and are characterized by lifelong infections and sporadic recurrences due to latent neuron infection. Upon reactivations, HSVs may manifest either, symptomatically or asymptomatically and be shed onto others through mucosae body fluids. Although, HSVs can produce severe disease in humans, such as life-threatening encephalitis and blindness, the most common symptoms are skin and mucosal lesions in the oro-facial and the genital areas. Nucleoside analogs with antiviral activity can prevent severe HSV infection, yet they are not very effective for treating skin manifestations produced by these viruses, as they only reduce in a few days at most the duration of lesions. Additionally, HSV variants that are resistant to these antivirals may arise, especially in immunosuppressed individuals. Thus, new antivirals that can reduce the severity and duration of these cutaneous manifestations would certainly be welcome. Here, we review currently available anti-herpetic therapies, novel molecules being assessed in clinical trials and new botanical compounds reported in the last 20 years with antiviral activities against HSVs that might represent future treatments against these viruses.
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Affiliation(s)
- Diana M. Álvarez
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Estefanía Castillo
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luisa F. Duarte
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José Arriagada
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nicolás Corrales
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mónica A. Farías
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Adolfo Henríquez
- Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
| | - Cristian Agurto-Muñoz
- Centro de Biotecnología, Universidad de Concepción, Concepción, Chile
- Departamento de Ciencia y Tecnología de Alimentos, Facultad de Farmacia, Universidad de Concepción, Concepción, Chile
| | - Pablo A. González
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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De Novo Assembly of Human Herpes Virus Type 1 (HHV-1) Genome, Mining of Non-Canonical Structures and Detection of Novel Drug-Resistance Mutations Using Short- and Long-Read Next Generation Sequencing Technologies. PLoS One 2016; 11:e0157600. [PMID: 27309375 PMCID: PMC4910999 DOI: 10.1371/journal.pone.0157600] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 05/31/2016] [Indexed: 02/01/2023] Open
Abstract
Human herpesvirus type 1 (HHV-1) has a large double-stranded DNA genome of approximately 152 kbp that is structurally complex and GC-rich. This makes the assembly of HHV-1 whole genomes from short-read sequencing data technically challenging. To improve the assembly of HHV-1 genomes we have employed a hybrid genome assembly protocol using data from two sequencing technologies: the short-read Roche 454 and the long-read Oxford Nanopore MinION sequencers. We sequenced 18 HHV-1 cell culture-isolated clinical specimens collected from immunocompromised patients undergoing antiviral therapy. The susceptibility of the samples to several antivirals was determined by plaque reduction assay. Hybrid genome assembly resulted in a decrease in the number of contigs in 6 out of 7 samples and an increase in N(G)50 and N(G)75 of all 7 samples sequenced by both technologies. The approach also enhanced the detection of non-canonical contigs including a rearrangement between the unique (UL) and repeat (T/IRL) sequence regions of one sample that was not detectable by assembly of 454 reads alone. We detected several known and novel resistance-associated mutations in UL23 and UL30 genes. Genome-wide genetic variability ranged from <1% to 53% of amino acids in each gene exhibiting at least one substitution within the pool of samples. The UL23 gene had one of the highest genetic variabilities at 35.2% in keeping with its role in development of drug resistance. The assembly of accurate, full-length HHV-1 genomes will be useful in determining genetic determinants of drug resistance, virulence, pathogenesis and viral evolution. The numerous, complex repeat regions of the HHV-1 genome currently remain a barrier towards this goal.
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Schubert A, Gentner E, Bohn K, Schwarz M, Mertens T, Sauerbrei A. Single nucleotide polymorphisms of thymidine kinase and DNA polymerase genes in clinical herpes simplex virus type 1 isolates associated with different resistance phenotypes. Antiviral Res 2014; 107:16-22. [PMID: 24747042 DOI: 10.1016/j.antiviral.2014.03.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/21/2014] [Accepted: 03/24/2014] [Indexed: 11/24/2022]
Abstract
The role of mutations in the thymidine kinase (TK, UL23) and DNA polymerase (pol, UL30) genes of herpes simplex virus (HSV) for development of different resistance phenotypes has to be exactly determined before genotypic resistance testing can be implemented in patient's care. Furthermore, the occurrence of cross-resistance is of utmost clinical importance. In this study, clinical HSV-1 isolates obtained between 2004 and 2011 from 26 patients after stem cell transplantation were examined in parallel by phenotypic and genotypic resistance testing. Thirteen isolates, which were phenotypically cross-resistant to acyclovir (ACV), penciclovir (PCV) and brivudin (BVDU), exhibited consistently frameshift or non-synonymous mutations in the TK gene known to confer resistance. One of these mutations (insertion of C at the nucleotide positions 1061-1065) has not been described before. Seven strains, phenotypically resistant to ACV and PCV and, except one each, sensitive to BVDU and resistant to foscarnet (FOS), carried uniformly resistance-related substitutions in the DNA pol gene. Finally, 3 isolates, resistant to ACV, PCV and 2 out of these also resistant to BVDU, had known but also unclear substitutions in the TK and DNA pol genes, and 3 isolates were completely sensitive. In conclusion, clinical ACV-resistant HSV-1 isolates, carrying resistance-associated mutations in the TK gene, can be regarded as cross-resistant to other nucleoside analogs such as BVDU. In contrast, clinical FOS-resistant HSV-1 strains which are cross-resistant to ACV may be sensitive to BVDU. This has to be considered for drug changes in antiviral treatment in case of ACV resistance.
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Affiliation(s)
- Axel Schubert
- Institute of Virology, German Reference Laboratory for CMV, University Hospital Ulm, Ulm, Germany
| | - Eva Gentner
- Institute of Virology, German Reference Laboratory for CMV, University Hospital Ulm, Ulm, Germany; Institute for Experimental Cancer Research, University Hospital Ulm, Ulm, Germany
| | - Kathrin Bohn
- Institute of Virology and Antiviral Therapy, German Reference Laboratory for HSV and VZV, Jena University Clinic, Jena, Germany
| | - Maximilian Schwarz
- Institute of Virology and Antiviral Therapy, German Reference Laboratory for HSV and VZV, Jena University Clinic, Jena, Germany
| | - Thomas Mertens
- Institute of Virology, German Reference Laboratory for CMV, University Hospital Ulm, Ulm, Germany
| | - Andreas Sauerbrei
- Institute of Virology and Antiviral Therapy, German Reference Laboratory for HSV and VZV, Jena University Clinic, Jena, Germany.
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Magee WC, Evans DH. The antiviral activity and mechanism of action of (S)-[3-hydroxy-2-(phosphonomethoxy)propyl] (HPMP) nucleosides. Antiviral Res 2012; 96:169-80. [PMID: 22960154 DOI: 10.1016/j.antiviral.2012.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 08/20/2012] [Accepted: 08/27/2012] [Indexed: 12/18/2022]
Abstract
One class of compounds that has shown promise as antiviral agents are the (S)-[3-hydroxy-2-(phosphonomethoxy)propyl] (HPMP) nucleosides, members of the broader class of acyclic nucleoside phosphonates. These HPMP nucleosides are nucleotide analogs and have been shown to be effective inhibitors of a wide range of DNA viruses. Prodrugs of these compounds, which achieve higher levels of the active metabolites within the cell, have an expanded activity spectrum that also includes RNA viruses and retroviruses. Because they are analogs of natural nucleotide substrates, HPMP nucleosides are predicted to target polymerases (DNA polymerases, RNA polymerases and reverse transcriptases), resulting in the inhibition of viral genome replication. Previous work using the replicative enzymes of different viruses including human cytomegalovirus (HCMV) and vaccinia virus DNA polymerases and human immunodeficiency virus type 1 (HIV-1) reverse transcriptase has shown that the activated forms of these compounds are substrates for viral polymerases and that incorporation of these compounds into either the primer strand or the template strand inhibits, but does not necessarily terminate, further nucleic acid synthesis. The activity of these compounds against other viruses that do not encode their own polymerases, like polyoma viruses and papilloma viruses, suggests that host cell DNA polymerases are also targeted. This complex mechanism of action and broad activity spectrum has implications for the development of resistance and host cell genome replication, and suggests these compounds may be effective against other viruses such as influenza virus, respiratory syncytial virus and Dengue virus. This class of nucleotide analogs also points to a potential avenue for the development of newer antivirals.
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Affiliation(s)
- Wendy C Magee
- Department of Medical Microbiology and Immunology, Li Ka Shing Institute of Virology, 6-020 Katz Group Centre, University of Alberta, Edmonton, AB, Canada T6G 2E1
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11
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Karaba AH, Cohen LK, Glaubach T, Kopp SJ, Reichek JL, Yoon HH, Zheng XT, Muller WJ. Longitudinal Characterization of Herpes Simplex Virus (HSV) Isolates Acquired From Different Sites in an Immune-Compromised Child: A New HSV Thymidine Kinase Mutation Associated With Resistance. J Pediatric Infect Dis Soc 2012; 1:116-24. [PMID: 23687576 PMCID: PMC3656553 DOI: 10.1093/jpids/pis009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 01/12/2012] [Indexed: 11/12/2022]
Abstract
BACKGROUND Herpes simplex virus resistance to acyclovir is well described in immune-compromised patients. Management of prolonged infection and recurrences in such patients may be problematic. METHODS A patient with neuroblastoma developed likely primary herpes gingivostomatitis shortly after starting a course of chemotherapy, with spread to the eye during treatment with acyclovir. Viral isolates were serially obtained from separate sites after treatment was begun and tested for susceptibility to acyclovir and foscarnet by plaque reduction and plating efficiency assays. The thymidine kinase and DNA polymerase genes from each isolate were sequenced. RESULTS Initial isolates from a throat swab, an oral lesion, and conjunctiva were resistant to acyclovir within 13 days of treatment. Subsequent isolates while on foscarnet were initially acyclovir-susceptible, but reactivation of an acyclovir-resistant isolate was subsequently documented while on acyclovir suppression. Genotypic analysis identified a previously unreported UL23 mutation in some resistant isolates. None of the amino acid changes identified in UL30 were associated with resistance. CONCLUSIONS Phenotypic and genotypic antiviral resistance of herpes simplex isolates may vary from different compartments and over time in individual immune-compromised hosts, highlighting the importance of obtaining cultures from all sites. Phenotypic resistance testing should be considered for isolates obtained from at-risk patients not responding to first-line therapy. Empiric combination treatment with multiple antivirals could be considered in some situations.
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Affiliation(s)
| | | | | | - Sarah J. Kopp
- Departments of Microbiology-Immunology,Pediatrics, and
| | | | - Hawke H. Yoon
- Ophthalmology, Northwestern University Feinberg School of Medicine
| | - Xiaotian T. Zheng
- Department of Pathology and Laboratory Medicine; Children's Memorial Hospital, Chicago, Illinois
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Sauerbrei A, Bohn K, Heim A, Hofmann J, Weissbrich B, Schnitzler P, Hoffmann D, Zell R, Jahn G, Wutzler P, Hamprecht K. Novel resistance-associated mutations of thymidine kinase and DNA polymerase genes of herpes simplex virus type 1 and type 2. Antivir Ther 2012; 16:1297-308. [PMID: 22155911 DOI: 10.3851/imp1870] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Studies to verify correlations between phenotypes and genotypes of herpes simplex virus (HSV) are an important tool to establish a database of resistance-associated mutations. METHODS In this study, 32 acyclovir (ACV)-resistant clinical HSV-1 and 4 ACV-resistant clinical HSV-2 isolates were examined in parallel by both phenotypic and genotypic resistance testing. Additionally, five non-viable HSV-1 strains and two non-viable HSV-2 strains with clinical resistance were included in genotypic resistance analysis. RESULTS All ACV-resistant HSV isolates showed cross-resistance to brivudin and penciclovir, and were sensitive to foscarnet and cidofovir. Acyclovir resistance was assigned to frameshift and single non-synonymous mutations of the thymidine kinase (TK) gene in 32 out of 37 HSV-1 strains and in 4 out of 6 HSV-2 strains. In three HSV-1 isolates, there were resistance-associated amino acid substitutions of the DNA polymerase (pol). Six substitutions in the TK and two in the DNA pol gene could not be attributed without doubt to either ACV resistance or natural gene polymorphism. Altogether, 10 resistance-related mutations in the TK and 1 in the DNA pol gene have not been reported previously. CONCLUSIONS The novel non-synonymous mutations found in this study enrich the knowledge about the genetic alterations of TK and DNA pol genes in ACV-resistant clinical HSV strains. Together with data from the literature, the findings justify the generation of a HSV database that contains resistance mutations associated with ACV resistance phenotype.
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Affiliation(s)
- Andreas Sauerbrei
- Institute of Virology and Antiviral Therapy, German Reference Laboratory for HSV and VZV, Jena University Clinic, Jena, Germany.
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13
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Henao-Martínez AF, Weinberg A, Waldman WJ, Levi ME. Successful treatment of acyclovir-resistant herpes simplex virus type 2 proctitis with leflunomide in an HIV-infected man. J Clin Virol 2012; 54:276-8. [PMID: 22465339 DOI: 10.1016/j.jcv.2012.02.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 02/28/2012] [Indexed: 10/28/2022]
Abstract
Human herpes simplex virus infections are very common and represent significant morbidity in the immunocompromised host. Patients with acyclovir resistant strains of HSV based on viral thymidine kinase gene mutations need alternative therapeutic approaches. Leflunomide has been shown to possess antiviral activity against several viruses. Herein we describe a case of acyclovir resistant HSV-2 proctitis in an HIV patient successfully treated with leflunomide without significant side effects.
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14
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Sellar RS, Peggs KS. Management of multidrug-resistant viruses in the immunocompromised host. Br J Haematol 2011; 156:559-72. [DOI: 10.1111/j.1365-2141.2011.08988.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Moses SE, Osborne W, Valappil M, Collin M, Lee D, Waugh S, Jackson G, Parry CM, Crowley B. Extensive oral herpes simplex virus type 1 infection in a haematopoietic stem cell transplant recipient not responding to aciclovir. J Clin Virol 2011; 52:67-9. [PMID: 21665532 DOI: 10.1016/j.jcv.2011.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 05/03/2011] [Indexed: 10/18/2022]
Affiliation(s)
- S E Moses
- Department of Virology, Health Protection Agency Microbiology Services, Newcastle, UK.
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16
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Strasfeld L, Chou S. Antiviral drug resistance: mechanisms and clinical implications. Infect Dis Clin North Am 2010; 24:809-33. [PMID: 20674805 DOI: 10.1016/j.idc.2010.07.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Antiviral drug resistance is an increasing concern in immunocompromised patient populations, where ongoing viral replication and prolonged drug exposure lead to the selection of resistant strains. Rapid diagnosis of resistance can be made by associating characteristic viral mutations with resistance to various drugs as determined by phenotypic assays. Management of drug resistance includes optimization of host factors and drug delivery, selection of alternative therapies based on knowledge of mechanisms of resistance, and the development of new antivirals. This article discusses drug resistance in herpesviruses and hepatitis B.
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Affiliation(s)
- Lynne Strasfeld
- Division of Infectious Diseases, Oregon Health & Science University, Portland, OR 97239, USA.
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17
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Goncharova IA, Rachkovskiĭ MI, Beloborodova EV, Gamal' Abd El'-Aziz Nasar K, Puzyrev VP. [Liver cirrhosis patogenetics: polymorphism of glutation S-transferase genes]. Mol Biol (Mosk) 2010; 44:431-8. [PMID: 20608166 DOI: 10.1134/s0026893310030118] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Association of deletion polymorphism in GSTT1 and GSTM1 genes and polymorphic variant A313G of GSTP1 gene with cirrhosis diseases and 4-year survival rate for the Tomsk region (West Siberia) patients were tested. Homozygous deletion of GSTM1 gene (null genotype) was a protective factor for alcoholic and mixed (HCV, HBV and alcohol) liver cirrhosis development. The patients from the joint group (all etiology forms) as well as having alcoholic and mixed cirrhosis had lower frequency of GSTM1 null genotype (39.2, 39.0, and 34.2%, respectively) in comparison with the control group (64.6%). The GSTM1 null genotype and GSTP1 gene A313G polymorphic variant correlated with the patients' survival rate. The patients survived in comparison with the dead had higher frequency of a GSTM1 null genotype (46.6 vs. 30.2%) and GSTP1 AA genotype (63.1 vs. 40.5%), and lower frequency of GSTP1 AG (A313G) genotype (31.1 vs. 51.2%). A survival rate was 2.5 times higher for patients having GSTP1 AA genotype in comparison with the GG and AG genotype carriers and 2 times higher for patients having GSTM1 null genotype than the gene carriers. A 4-year fatal case probability was 2.3 times higher among the patients having heterozygous AG GSTP1 genotype in comparison with homozygous AA and GG genotype carriers.
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18
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Strasfeld L, Chou S. Antiviral drug resistance: mechanisms and clinical implications. Infect Dis Clin North Am 2010; 24:413-37. [PMID: 20466277 DOI: 10.1016/j.idc.2010.01.001] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Antiviral drug resistance is an increasing concern in immunocompromised patient populations, where ongoing viral replication and prolonged drug exposure lead to the selection of resistant strains. Rapid diagnosis of resistance can be made by associating characteristic viral mutations with resistance to various drugs as determined by phenotypic assays. Management of drug resistance includes optimization of host factors and drug delivery, selection of alternative therapies based on knowledge of mechanisms of resistance, and the development of new antivirals. This article discusses drug resistance in herpesviruses and hepatitis B.
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Affiliation(s)
- Lynne Strasfeld
- Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, mail code L457, Portland, OR 97239, USA.
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19
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Phenotypic and genotypic characterization of acyclovir-resistant clinical isolates of herpes simplex virus. Antiviral Res 2010; 86:246-52. [PMID: 20211650 DOI: 10.1016/j.antiviral.2010.03.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 02/19/2010] [Accepted: 03/01/2010] [Indexed: 11/24/2022]
Abstract
Sixteen herpes simplex virus type 1 (HSV-1) and four type 2 (HSV-2) isolates resistant to acyclovir (ACV) were characterized retrospectively for drug resistance. Phenotypic testing was performed by means of tetrazolium reduction assay and genotypic analysis was carried out by sequencing of thymidine kinase (TK) and DNA-polymerase (pol) genes. All strains were characterized as cross-resistant to penciclovir, brivudin and susceptible to cidofovir. In addition, three strains were resistant to foscarnet. Genotypic analysis revealed two to seven non-synonymous mutations in the TK gene of HSV-1 and one to seven non-synonymous mutations in the DNA pol gene of HSV-1 and 2 associated with the gene polymorphism. Seventeen strains contained at least one non-synonymous resistant-related mutation in the TK gene and three strains, which were additionally foscarnet-resistant, revealed one resistance-associated mutation in the DNA pol gene. In most strains, resistant-related mutations in TK gene represented frameshift mutations and single non-synonymous nucleotide substitutions of conserved gene regions. However, numerous amino acid changes could not be interpreted clearly as accounting for resistance. In conclusion, further studies, e.g. site-directed mutagenesis experiments are required to characterize mutations of the TK and DNA pol genes in ACV-resistant viral strains as part of viral gene polymorphism or as cause of drug resistance.
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20
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Frobert E, Cortay JC, Ooka T, Najioullah F, Thouvenot D, Lina B, Morfin F. Genotypic detection of acyclovir-resistant HSV-1: characterization of 67 ACV-sensitive and 14 ACV-resistant viruses. Antiviral Res 2008; 79:28-36. [PMID: 18336925 DOI: 10.1016/j.antiviral.2008.01.153] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 01/18/2008] [Accepted: 01/28/2008] [Indexed: 10/22/2022]
Abstract
Infections due to herpes simplex virus (HSV) resistant to acyclovir (ACV) represent an important clinical concern in immunocompromised patients. In order to switch promptly to an appropriate treatment, rapid viral susceptibility assays are required. We developed herein a genotyping analysis focusing on thymidine kinase gene (TK) mutations in order to detect acyclovir-resistant HSV in clinical specimens. A total of 85 HSV-1 positive specimens collected from 69 patients were analyzed. TK gene could be sequenced directly for 81 clinical specimens (95%) and 68 HSV-1 specimens could be characterized as sensitive or resistant by genotyping (84%). Genetic characterization of 67 susceptible HSV-1 specimens revealed 10 polymorphisms never previously described. Genetic characterization of 14 resistant HSV-1 revealed 12 HSV-1 with either TK gene additions/deletions (8 strains) or substitutions (4 strains) and 2 HSV-1 with no mutation in the TK gene. DNA polymerase gene was afterwards explored. With this rapid PCR-based assay, ACV-resistant HSV could be detected directly in clinical specimens within 24 h.
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Affiliation(s)
- Emilie Frobert
- Laboratoire de Virologie, Centre de Biologie et de Pathologie Est, Hospices Civils de Lyon, Bron Cedex, Lyon, France.
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21
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[Genotyping diagnosis of acyclovir resistant herpes simplex virus]. ACTA ACUST UNITED AC 2007; 55:504-11. [PMID: 17920786 DOI: 10.1016/j.patbio.2007.08.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Accepted: 08/30/2007] [Indexed: 11/23/2022]
Abstract
Herpes simplex virus resistant to acyclovir (ACV) is a major concern among immunocompromised patients. ACV resistance might be due to mutations located in one of the two genes involved in ACV mechanism of action, the thymidine kinase gene (TK, involved in 95% of the cases) and the DNA polymerase gene. TK gene mutations consist, in half of the cases, in nucleotide insertion or deletion, occurring most of the time in G or C homopolymers considered as hot spots. Half of the other cases involves nucleotide substitutions leading to amino acids substitutions. Studies of sensitive strains revealed a high degree of TK polymorphism, many mutations being not implied in ACV resistance. At the present time, resistance detection can be performed by phenotypic tests that require virus culture and results cannot be given to the physician before 7 to 10 days. Genotyping diagnosis performed directly from clinical samples would allow to detect resistance more rapidly, in order to switch quickly to an appropriate treatment by foscarnet or cidofovir.
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22
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Andrei G, Fiten P, Froeyen M, Clercq ED, Opdenakker G, Snoeck R. DNA Polymerase Mutations in Drug-Resistant Herpes Simplex Virus Mutants Determine In Vivo Neurovirulence and Drug-Enzyme Interactions. Antivir Ther 2007. [DOI: 10.1177/135965350701200502] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mutations in the thymidine kinase and DNA polymerase genes of herpes simplex virus (HSV) might confer resistance to antiviral drugs, particularly in immunocompromised patients who suffer from chronic and/or disseminated lesions. The patterns of cross-resistance and neurovirulence in mice of several DNA polymerase mutants selected under pressure of foscarnet (PFA) and different acyclic nucleoside phosphonates (ANPs), including ( S)-3-hydroxy-2-phosphonylmethoxypropyl (HPMP) derivatives of adenine (HPMPA) and cytosine (HPMPC, cidofovir) and 2-phosphonylmethoxyethyl (PME) derivatives of adenine (PMEA) and 2,6-diaminopurine (PMEDAP), were investigated. The mutants were derived from the HSV-1 strain KOS following either single or multiple steps of selection with PFA (V714M, A719V, S724N and T821M), PMEA (S724N, L802F and R959H), PMEDAP (Q618H, S724N, S724N+D1070N), HPMPC (V573M, R700M and K960R) or HPMPA (W998L, L1007M and I1028T). These amino acid substitutions were located in different subdomains of the HSV-1 DNA polymerase, either in conserved or non-conserved regions. The sensitivity of the mutants to a new class of ANPs, the 6-(2-[phosphonomethoxy]alkoxy)pyrimidines HPMPO-DAPy and PMEO-DAPy, was investigated. Cross-resistance between the HPMP derivatives and HPMPO-DAPy, on the one hand, and between the PME derivatives and PMEO-DAPy, on the other hand, was observed. Different degrees of cross-resistance between PME derivatives, PMEO-DAPy, PFA and acyclovir were noticed. The mutants ranged from exhibiting near wild-type neurovirulence (V714M, A719V, S724N and L1007M) to significant attenuation (Q618H, S724N+D1070N, L802F, R700M, K960R, W998L and I1028T) or higher levels of attenuation (V573M). It appears that drug-resistant mutants arising under the pressure of HPMP derivatives have the lowest levels of neurovirulence.
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Affiliation(s)
- Graciela Andrei
- Laboratory of Virology, Rega Institute for Medical Research, K U Leuven, Belgium
| | - Pierre Fiten
- Laboratory of Immunobiology, Rega Institute for Medical Research, K U Leuven, Belgium
| | - Matheus Froeyen
- Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, K U Leuven, Belgium
| | - Erik De Clercq
- Laboratory of Virology, Rega Institute for Medical Research, K U Leuven, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Rega Institute for Medical Research, K U Leuven, Belgium
| | - Robert Snoeck
- Laboratory of Virology, Rega Institute for Medical Research, K U Leuven, Belgium
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Ramaswamy M, Geretti AM. Interactions and management issues in HSV and HIV coinfection. Expert Rev Anti Infect Ther 2007; 5:231-43. [PMID: 17402838 DOI: 10.1586/14787210.5.2.231] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Significant synergistic interactions have been observed between HIV and herpes simplex virus (HSV). HIV-induced immune compromise can cause frequent and persistent HSV disease, while poorly controlled HSV replication may influence HIV pathogenicity and transmission. HSV-2 seroprevalence is high in HIV-infected cohorts worldwide, with rates of over 80% for HSV-1 and ranging from 33% to more than 80% for HSV-2. As seen in HIV-negative individuals, HSV-2 coinfection is associated with female gender, older age and black ethnicity. HSV infection is commonly under-diagnosed in HIV-infected individuals, although the use of PCR for HSV detection in mucocutaneous swabs and HSV type-specific serology can improve the diagnostic yield. In HIV-1-infected patients with frequent clinical episodes of HSV reactivation, suppressive antiviral therapy may prove beneficial in controlling HSV disease while also reducing HSV-mediated promotion of HIV replication. Antiretroviral therapy leads to a gradual recovery of HSV-specific T-cell responses and a reduction in HSV-related morbidity, indicating that successful management of coinfection should target both HIV and HSV replication. The aim of this review is to address the more speculative issues surrounding the management of HSV/HIV coinfection and to summarize the data that inform them.
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Affiliation(s)
- Meghna Ramaswamy
- Royal Free Hospital and Royal Free & University College Medical School, Department of Virology, Pond Street, London NW3 2QG, UK.
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