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Journal of Clinical Virology : the... Oct 2023Antiviral resistance in human herpes simplex viruses (HSV) remains a significant clinical challenge in immunocompromised populations. Although molecular tests have...
BACKGROUND
Antiviral resistance in human herpes simplex viruses (HSV) remains a significant clinical challenge in immunocompromised populations. Although molecular tests have largely replaced viral culture for HSV diagnosis and molecular antiviral resistance testing is available for many viruses, HSV resistance testing continues to rely on phenotypic, viral culture-based methods, requiring weeks for results. Consequently, treatment of suspected HSV resistance remains largely empiric.
METHODS
We used HSV whole genome sequencing and a database of previously characterized HSV acyclovir and foscarnet resistance mutations to evaluate the performance of genotypic antiviral resistance testing among 19 control strains compared to in-house plaque reduction assay (PRA) and 25 clinical isolates sent for reference lab PRA antiviral resistance testing.
RESULTS
Among control strains, 23/29 (79.3%) results were concordant, 5 (17.2%) were indeterminate, and 1 (3.4%) was discordant. Indeterminate results were caused by variants of uncertain significance (VUS), including mutations without published phenotypes and mutations with contradictory results. Among clinical isolates, 14/40 (35%) results were concordant, 17 (42.5%) were indeterminate, and 9 (22.5%) were discordant. All discordant results were in reportedly phenotypically-susceptible HSV-1 strains yet possessed resistance mutations. Three contained resistant subpopulations. 6/8 (75%) discordant phenotypes were concordant with resistant genotypes upon repeat PRA.
CONCLUSIONS
These data support the combination of genotypic and phenotypic testing to diagnose HSV resistance more accurately and likely more rapidly than phenotypic testing alone. Genotypic context of resistance mutations and the ability of viral strains to form plaques in culture may affect phenotypic resistance results, highlighting the limitations of PRA alone as a gold standard method.
Topics: Humans; Antiviral Agents; Herpesvirus 2, Human; Acyclovir; Foscarnet; Herpesvirus 1, Human; Genotype; Drug Resistance, Viral; Herpes Simplex
PubMed: 37586184
DOI: 10.1016/j.jcv.2023.105554 -
Antimicrobial Agents and Chemotherapy Feb 2021The objectives of this study were to characterize the role of the , , and genes in fosfomycin resistance in and evaluate the use of sodium phosphonoformate (PPF) in...
The objectives of this study were to characterize the role of the , , and genes in fosfomycin resistance in and evaluate the use of sodium phosphonoformate (PPF) in combination with fosfomycin. Seven clinical isolates of and the reference strain (ATCC 700721) were used, and their genomes were sequenced. Δ, Δ, and Δ mutants were constructed from two isolates and ATCC 700721. Fosfomycin susceptibility testing was done by the gradient strip method. Synergy between fosfomycin and PPF was studied by checkerboard assay and analyzed using SynergyFinder. Spontaneous fosfomycin mutant frequencies at 64 and 512 mg/liter, activity using growth curves with fosfomycin gradient concentrations (0 to 256mg/liter), and time-kill assays at 64 and 307 mg/liter were evaluated with and without PPF (0.623 mM). The MICs of fosfomycin against the clinical isolates ranged from 16 to ≥1,024 mg/liter. The addition of 0.623 mM PPF reduced fosfomycin MIC between 2- and 8-fold. Deletion of led to a 32-fold decrease. Synergistic activities were observed with the combination of fosfomycin and PPF (most synergistic area at 0.623 mM). The lowest fosfomycin-resistant mutant frequencies were found in Δ mutants, with decreases in frequency from 1.69 × 10 to 1.60 × 10 for 64 mg/liter of fosfomycin. In the final growth monitoring and time-kill assays, fosfomycin showed a bactericidal effect only with the deletion of and not with the addition of PPF. We conclude that gene inactivation leads to a decrease in fosfomycin resistance in The pharmacological approach using PPF did not achieve enough activity, and the effect decreased with the presence of fosfomycin-resistant mutations.
Topics: Anti-Bacterial Agents; Foscarnet; Fosfomycin; Klebsiella pneumoniae; Microbial Sensitivity Tests; beta-Lactamases
PubMed: 33361305
DOI: 10.1128/AAC.01911-20 -
Acta Dermatovenerologica Alpina,... 2011Foscarnet is used to treat herpes viruses, including drug-resistant cytomegalovirus (CMV) and herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2). There are some...
Foscarnet is used to treat herpes viruses, including drug-resistant cytomegalovirus (CMV) and herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2). There are some reports of intravenous foscarnet-induced penile and vulvar ulceration. The authors report a case of the development of severe penile ulcers after the initiation of intravenous foscarnet therapy.
Topics: Acquired Immunodeficiency Syndrome; Adult; Antiviral Agents; Foscarnet; Humans; Male; Penile Diseases; Reverse Transcriptase Inhibitors; Ulcer
PubMed: 21879205
DOI: No ID Found -
Journal of Virology Apr 1976Growth of lymphoblastoid cells (B95-8, Raji) is not inhibited by the presence of 0.4 mM phosphonoacetic acid. The synthesis of Epstein-Barr virus (EBV) in the producer...
Growth of lymphoblastoid cells (B95-8, Raji) is not inhibited by the presence of 0.4 mM phosphonoacetic acid. The synthesis of Epstein-Barr virus (EBV) in the producer line B95-8 is completely inhibited, as shown by the total inhibition of viral capsid antigen synthesis. Early viral antigens are made normally in the presence of phosphonoacetic acid, but EBV DNA synthesis is blocked in cells entering the productive cycle. Nonproducer cells in the population replicate the resident EBV DNA by a mechanism that is resistant to phosphonoacetic acid. These results are consistant with the hypotheses that EBV DNA is replicated by two mechanisms, one in the noninduced cell and a different mechanism in the producer cell, and that prior replication of EBV DNA, probably by the second mode, is a prerequisite for late gene expression.
Topics: Acetates; Antigens, Viral; Cell Line; DNA Replication; DNA, Viral; Enzyme Inhibitors; Herpesvirus 4, Human; Organophosphorus Compounds; Virus Replication
PubMed: 176457
DOI: 10.1128/JVI.18.1.151-155.1976 -
Journal of Enzyme Inhibition and... Dec 2018Small molecule inhibitors have a powerful blocking action on viral polymerases. The bioavailability of the inhibitor, nevertheless, often raise a significant selectivity...
Small molecule inhibitors have a powerful blocking action on viral polymerases. The bioavailability of the inhibitor, nevertheless, often raise a significant selectivity constraint and may substantially limit the efficacy of therapy. Phosphonoacetic acid has long been known to possess a restricted potential to block DNA biosynthesis. In order to achieve a better affinity, this compound has been linked with natural nucleotide at different positions. The structural context of the resulted conjugates has been found to be crucial for the acquisition by DNA polymerases. We show that nucleobase-conjugated phosphonoacetic acid is being accepted, but this alters the processivity of DNA polymerases. The data presented here not only provide a mechanistic rationale for a switch in the mode of DNA synthesis, but also highlight the nucleobase-targeted nucleotide functionalization as a route for enhancing the specificity of small molecule inhibitors.
Topics: DNA-Directed DNA Polymerase; Enzyme Inhibitors; HIV-1; Molecular Structure; Moloney murine leukemia virus; Nucleotides; Phosphonoacetic Acid
PubMed: 29372656
DOI: 10.1080/14756366.2017.1417275 -
American Journal of Kidney Diseases :... Sep 1998
Topics: AIDS-Related Opportunistic Infections; Antiviral Agents; Crystallization; Cytomegalovirus Retinitis; Foscarnet; Humans; Kidney Failure, Chronic; Kidney Glomerulus
PubMed: 9740173
DOI: 10.1053/ajkd.1998.v32.pm9740173 -
ACS Biomaterials Science & Engineering Apr 2022[ZrO][(FCN)(OH)] and Gd[FCN] inorganic-organic hybrid nanoparticles (IOH-NPs) are novel saline antiviral nanocarriers with foscarnet (FCN) as a drug anion. FCN as a...
[ZrO][(FCN)(OH)] and Gd[FCN] inorganic-organic hybrid nanoparticles (IOH-NPs) are novel saline antiviral nanocarriers with foscarnet (FCN) as a drug anion. FCN as a pyrophosphate analogue serves as a prototype of a viral DNA polymerase inhibitor. FCN is used for the treatment of herpesvirus infections, including the drug-resistant cytomegalovirus (CMV) and herpes simplex viruses, HSV-1 and HSV-2. The novel [ZrO][(FCN)(OH)] and Gd[FCN] IOH-NPs are characterized by aqueous synthesis, small size (20-30 nm), low material complexity, high biocompatibility, and high drug load (up to 44 wt % FCN per nanoparticle). The antiviral activity of the FCN-type IOH-NPs is probed for the human cytomegalovirus (HCMV). Moreover, the uptake of FCN-type IOH-NPs into vesicles, cytoplasm, and nuclei of nonphagocytic lung epithelial cells is evaluated. As a result, a promising antiviral activity of the FCN-type IOH-NPs that significantly outperforms freely dissolved FCN at the level of clinical formulations is observed, encouraging a future use of FCN-type IOH-NPs for the delivery of antivirals against respiratory viruses.
Topics: Antiviral Agents; Cytomegalovirus; Foscarnet; Herpesvirus 1, Human; Humans; Nanoparticles
PubMed: 35344659
DOI: 10.1021/acsbiomaterials.2c00074 -
Journal of Nanobiotechnology Jul 2022Cytomegalovirus (CMV) pneumonia is a major cause of morbidity and mortality in immunodeficiency individuals, including transplant recipients and Acquired Immune...
BACKGROUND
Cytomegalovirus (CMV) pneumonia is a major cause of morbidity and mortality in immunodeficiency individuals, including transplant recipients and Acquired Immune Deficiency Syndrome patients. Antiviral drugs ganciclovir (GCV) and phosphonoformate (PFA) are first-line agents for pneumonia caused by herpesvirus infection. However, the therapy suffers from various limitations such as low efficiency, drug resistance, toxicity, and lack of specificity.
METHODS
The antiviral drugs GCV and PFA were loaded into the pH-responsive nanoparticles fabricated by poly(lactic-co-glycolic acid) (PLGA) and 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and further coated with cell membranes derived from bone marrow mesenchymal stem cells to form artificial stem cells, namely MPDGP. We evaluated the viral suppression effects of MPDGP in vitro and in vivo.
RESULTS
MPDGP showed significant inflammation tropism and efficient suppression of viral replication and virus infection-associated inflammation in the CMV-induced pneumonia model. The synergistic effects of the combination of viral DNA elongation inhibitor GCV and viral DNA polymerase inhibitor PFA on suppressing the inflammation efficiently.
CONCLUSION
The present study develops a novel therapeutic intervention using artificial stem cells to deliver antiviral drugs at inflammatory sites, which shows great potential for the targeted treatment of pneumonia. To our best knowledge, we are the first to fabricate this kind of artificial stem cell to deliver antiviral drugs for pneumonia treatment.
Topics: Antiviral Agents; Cytomegalovirus; Cytomegalovirus Infections; Fatty Acids, Monounsaturated; Foscarnet; Ganciclovir; Humans; Inflammation; Nanoparticle Drug Delivery System; Pneumonia; Polylactic Acid-Polyglycolic Acid Copolymer; Quaternary Ammonium Compounds; Stem Cells
PubMed: 35842662
DOI: 10.1186/s12951-022-01547-x -
Prophylaxis against fungal infections and cytomegalovirus disease after bone marrow transplantation.Oncology (Williston Park, N.Y.) Dec 2000Among the serious complications associated with bone marrow transplantation are invasive fungal infections caused by organisms such as Candida and Aspergillus species... (Review)
Review
Among the serious complications associated with bone marrow transplantation are invasive fungal infections caused by organisms such as Candida and Aspergillus species and end-organ disease caused by cytomegalovirus (CMV). Successful prevention of these complications can have a significant impact on morbidity and mortality. The primary option for prophylaxis against fungal infections is fluconazole (Diflucan). Low doses of intravenous amphotericin B may be useful where there is a higher rate of aspergillosis. Itraconazole (Sporanox) and nasal amphotericin B are other options that have been less well studied. The development of fluconazole-resistant candidiasis may become problematic. Ganciclovir (Cytovene) is useful for the prevention of end-organ disease caused by CMV but carries a significant risk for neutropenia. New techniques for the early detection of CMV infection should allow prophylaxis to be targeted to patients at highest risk of developing CMV disease. It is critical to clearly define the risk factors for fungal and CMV disease in the individual patient in order to minimize adverse effects and provide the optimal prophylactic benefit.
Topics: Antifungal Agents; Antiviral Agents; Bone Marrow Transplantation; Cytomegalovirus Infections; Foscarnet; Ganciclovir; Humans; Mycoses; Opportunistic Infections; Prognosis; Retrospective Studies; Surgical Wound Infection
PubMed: 11212856
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Jun 2021Amino acid substitutions conferring resistance of herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) to foscarnet (PFA) are located in the genes and ,...
Amino acid substitutions conferring resistance of herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) to foscarnet (PFA) are located in the genes and , respectively, encoding the DNA polymerase (pol). In this study, we analyzed the impact of substitutions located in helix K and region II that are involved in the conformational changes of the DNA pol. Theoretical substitutions were identified by sequences alignment of the helix K and region II of human herpesviruses (susceptible to PFA) and bacteriophages (resistant to PFA) and introduced in viral genomes by recombinant phenotyping. We characterized the susceptibility of HSV-1 and HCMV mutants to PFA. In UL30, the substitutions I619K (helix K), V715S, and A719T (both in region II) increased mean PFA 50% effective concentrations (ECs) by 2.5-, 5.6-, and 2.0-fold, respectively, compared to the wild type (WT). In UL54, the substitution Q579I (helix K) conferred hypersusceptibility to PFA (0.17-fold change), whereas the substitutions Q697P, V715S, and A719T (all in region II) increased mean PFA ECs by 3.8-, 2.8- and 2.5-fold, respectively, compared to the WT. These results were confirmed by enzymatic assays using recombinant DNA pol harboring these substitutions. Three-dimensional modeling suggests that substitutions conferring resistance/hypersusceptibility to PFA located in helix K and region II of UL30 and UL54 DNA pol favor an open/closed conformation of these enzymes, resulting in a lower/higher drug affinity for the proteins. Thus, this study shows that both regions of UL30 and UL54 DNA pol are involved in the conformational changes of these proteins and can influence the susceptibility of both viruses to PFA.
Topics: Amino Acid Substitution; Antiviral Agents; Cytomegalovirus; DNA-Directed DNA Polymerase; Drug Resistance, Viral; Foscarnet; Herpesvirus 1, Human; Humans; Mutation
PubMed: 33875432
DOI: 10.1128/AAC.00390-21