Herpes Simplex Virus Isolates Research Articles

The Contribution of Multiplex Polymerase Chain Reaction in the Diagnosis of Central Nervous System Infections in Intensive Care Units.

Introduction The aim of this study was to evaluate the contribution and limits of BioFire® FilmArray® meningitis/encephalitis panel (FA MEP) polymerase chain reaction (PCR) (bioMérieux, Marcy-l'Étoile, France) (product references: LLC RFIT-ASY-0118) coupled with bacterial and fungal culture in the diagnosis of central nervous system infections (CNSIs). Methods This was a retrospective observational study including all patients (adults and children) hospitalized in the intensive care units (ICUs) of a Moroccan university hospital, who benefited from multiplex PCR on a cerebrospinal fluid (CSF) sample. Results A total of 112 PCRs were performed, with a positivity rate of 18%. Bacterial etiology was the most frequent (70%), represented mainly by Streptococcus pneumoniae (45%), followed by viruses (25%), with four isolates of Herpes simplex virus (HSV) 1. On 94 samples, there was an agreement between the culture and PCR results. Their discordance was found in 18 cases, including 16 suspected CNSIs recovered only by PCR and two diagnoses confirmed only by bacterial culture. Conclusion This study revealed the significant impact of multiplex PCR on the early and targeted diagnostic and therapeutic management of infectious meningitis and meningoencephalitis in intensive care unit patients.

Diagnosis and management chronic anemia in herpes simplex virus (HSV) type 1 infection

Herpes Simplex Virus type 1 (HSV-1) is usually the cause of oral infection. This infection oftenprecedes the development of this chronic anemia, and it is reasonable that the blood in circulation through virusinfectedtissue becomes contaminated with virus particles on the red cell surface. These virus-contaminated redblood cells may stimulate the reticuloendothelial system to produce antibodies that destroy the red blood cells andlead to anemia. Describe the clinical manifestations, pathogenesis, laboratory examination, diagnosis, and therapiesfor managing Chronic Anemia in HSV-1 infections. (HSV) Infection 1 causes infections above the waist majority oforal and pharyngeal and can be transmitted through direct contact with infected individuals. Prodromal symptomspreceded HSV-1 infection for 1 or 2 days consisting of fever, headache, malaise, arthralgia, and submandibularlymphadenopathy; subsequently, small blisters appear and quickly rupture, leaving shallow round discrete ulcers atall portions of the mouth. Diagnosis of anemia and HSV type 1 infection requires a complete history, clinicalexamination, and laboratory examinations (anti-HSV 1 IgG and IgM) or HSV isolation. Symptomatic treatment withantipyretics/analgesics, local antiseptics, vitamins, a soft diet, and adequate fluid intake is usually sufficient.Antiviral medication, either systemically or topically, may help if the infection is identified early in the prodromalstage. Conclusion: Chronic Anemia and HSV Type I infection should be diagnosed and managed with completeanamnesis, clinical manifestation, and laboratory examination.KEYWORDS: Infection, HSV-1, Anemia, Diagnosis, Management

Isolation, characterization and acyclovir susceptibility of herpes simplex virus isolates among immunocompromised patients.

Introduction:Herpes simplex virus (HSV) Type 2 primarily causes genital herpes, while HSV Type 1 is responsible for oral and facial lesions. The objective of this study was to isolate and characterize HSV from herpetic lesions among human immunodeficiency virus (HIV) infected patients and to evaluate their acyclovir susceptibility pattern.Materials and Methods:Blister fluid and swabs from ulcers were collected from patients with clinical diagnosis of HSV infection among patients attending the HIV clinic of two tertiary care centers – Medical College, Kolkata, and School of Tropical Medicine, Kolkata. These samples were cultured in the Vero cell line. Growth of virus was noted by observing the characteristic cytopathic effect of HSV, which was further confirmed by immunofluorescence and polymerase chain reaction (PCR). These isolates were then subjected to the Vero cells with serial dilutions of acyclovir for determining the susceptibility pattern.Results:Among the 52 samples received, 8 (15.38%) showed growth of HSV. After confirmation by immunofluorescence and PCR, all seven isolates from genital samples were identified as HSV-2 and the lone isolate from oral lesion was confirmed as HSV 1. Out of the eight isolates, 25% showed resistance to acyclovir. The overall isolation rate was more from genital blister than genital ulcer which was 46.15% and 2.86%, respectively.Conclusion:HSV was isolated in 15.38% of cases of clinical herpes. There was a higher isolation rate of virus from blister fluid as compared to ulcer scrapings. Acyclovir resistance in 25% of cases is alarmingly high.

TREATMENT OF PREGNANT WOMEN WITH A POLYHYDRAMON

Introduction. Treatment of polyhydramnios as a consequence of the infectious processis a difficultt ask because it requires urgent results. In the case of in sensitivity to conditionally pathogenic or pathogenic microflora, or the presence of viruses, delay in treatment can lead to intrauterine infection of the fetus.The aim of the study. To evaluate the efficacy of treatment of viral genesis polyhydramnion.Materials and Methods. Clinical and laboratory examination and treatmentof 60 pregnant women with polyhydramnion and the presence of an acute respiratory viral disease or isolated herpes simplex virus. The methods of study used were external obstetric examination, ultrasound, microscopic, bacteriological, immunofluorescence, enzyme immunoassay.Results. Рregnant women are divided in to two subgroups: the first subgroup immediately assigned immunocorrectiveantiviral drugs (n=30), the second – antimicrobial drugs, which proved to be ineffective, leading to changes in treatment (n=30). For the treatment immunocorrective preparations of flavonoidgly cosides are used – drops in a dose of 12 drops twice a day per os for 10-15 minutes before meals. After 7-10 days of application of the drug in 67 % of polyhydramnion decreased, in 14 days in 87 %, no signs of polyhydramnion.Conclusions. The pathogenetic treatment of polyhydramnion the use of antiviral drugs is a safe highly effective method of treating polyhydramnion, leads to recovery in 87% within 10-14 days, in other cases, to positive dynamics, which requires long-term treatment.

Antiviral resistance in herpes simplex virus and varicella-zoster virus infections: diagnosis and management.

Aciclovir (ACV) is the first-line drug for the management of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections. Long-term administration of ACV for the treatment of severe infections in immunocompromised patients can lead to the development of drug resistance. Furthermore, the emergence of isolates resistant to ACV is increasingly recognized in immunocompetent individuals with herpetic keratitis. This review describes the mechanisms involved in drug resistance for HSV and VZV, the laboratory diagnosis and management of patients with infections refractory to ACV therapy. Genotypic testing is more frequently performed for the diagnosis of infections caused by drug-resistant HSV or VZV isolates. Molecular biology-based systems for the generation of recombinant viruses have been developed to link unknown mutations with their drug phenotypes. Fast and sensitive methods based on next-generation sequencing will improve the detection of heterogeneous viral populations of drug-resistant viruses and their temporal changes during antiviral therapy, which could allow better patient management. Novel promising compounds acting on targets that differ from the viral DNA polymerase are under clinical development. Antiviral drug resistance monitoring for HSV and VZV is required for a rational use of antiviral therapy in high-risk populations.

Prevalence of Intrathecal Acyclovir Resistant Virus in Herpes Simplex Encephalitis Patients.

Herpes simplex encephalitis (HSE) is a life-threatening complication of herpes simplex virus (HSV) infection. Acyclovir (ACV) is the antiviral treatment of choice, but may lead to emergence of ACV-resistant (ACVR) HSV due to mutations in the viral UL23 gene encoding for the ACV-targeted thymidine kinase (TK) protein. Here, we determined the prevalence of intrathecal ACVR–associated HSV TK mutations in HSE patients and compared TK genotypes of sequential HSV isolates in paired cerebrospinal fluid (CSF) and blister fluid of mucosal HSV lesions. Clinical samples were obtained from 12 HSE patients, encompassing 4 HSV type 1 (HSV-1) and 8 HSV-2 encephalitis patients. HSV DNA load was determined by real-time PCR and complete HSV TK gene sequences were obtained by nested PCR followed by Sanger sequencing. All HSV-1 HSE patients contained viral TK mutations encompassing 30 unique nucleotide and 13 distinct amino acid mutations. By contrast, a total of 5 unique nucleotide and 4 distinct amino acid changes were detected in 7 of 8 HSV-2 patients. Detected mutations were identified as natural polymorphisms located in non-conserved HSV TK gene regions. ACV therapy did not induce the emergence of ACVR-associated HSV TK mutations in consecutive CSF and mucocutaneous samples of 5 individual patients. Phenotypic susceptibility analysis of these mucocutaneous HSV isolates demonstrated ACV-sensitive virus in 2 HSV-1 HSE patients, whereas in two HSV-2 HSE patients ACVR virus was detected in the absence of known ACVR-associated TK mutations. In conclusion, we did not detect intrathecal ACVR-associated TK mutations in HSV isolates obtained from 12 HSE patients.

Subclinical generation of acyclovir-resistant herpes simplex virus with mutation of homopolymeric guanosine strings during acyclovir therapy

BackgroundSuppressive therapy in patients with genital herpes has been used in Japan since 2006. Susceptibility and resistance of herpes simplex virus (HSV)-2 to acyclovir were examined in genital isolates from patients receiving suppressive therapy and compared with those from those naïve to acyclovir and receiving episodic treatment with acyclovir. ObjectiveThe aim of this study was to analyze the effect of acyclovir use on the susceptibility to acyclovir and analysis of the thymidine kinase gene by acyclovir treatment. MethodsGenital HSV isolates were obtained from three patients groups. Susceptibility to acyclovir, the frequency of acyclovir-resistant clones and mutations in the thymidine kinase gene of acyclovir-resistant clones were determined. ResultsSusceptibility to ACV was significantly higher in isolates from patients receiving suppressive therapy than those naïve to acyclovir and receiving episodic treatment, but the frequencies of resistant clones were similar among the three groups. Mutation in guanosine homopolymeric strings (G-string mutation) was significantly more frequent in clones during episodic treatment and suppressive therapy than clones from patients naïve to ACV. The frequency of G-string mutation was significantly less frequent in isolates from patients naïve to ACV than those experienced ACV therapy. ConclusionThe frequency of acyclovir-resistant mutants was not increased by episodic and suppressive therapy, but exposure to acyclovir significantly generated G-string mutations, possibly induced by acyclovir. Acyclovir therapy had no substantial effects on the susceptibility of HSV-2 or frequency of resistant virus but did generate subclinical G-string mutants in patients’ HSV-2.

Isolated herpes simplex virus pneumonia in children

Disseminated herpes simplex virus (HSV) infection is a well recognized condition in infants and children. However, the diagnosis of isolated HSV pneumonia, without evidence of other organ involvement, in this population is rare. We present a case series of isolated HSV pneumonia in four patients, all of which survived this acute illness with normal neurological outcome. Clinical features, diagnostic approaches, intensive care management, and antiviral drug therapy are reviewed.

Genome Sequencing and Analysis of Geographically Diverse Clinical Isolates of Herpes Simplex Virus 2.

Herpes simplex virus 2 (HSV-2), the principal causative agent of recurrent genital herpes, is a highly prevalent viral infection worldwide. Limited information is available on the amount of genomic DNA variation between HSV-2 strains because only two genomes have been determined, the HG52 laboratory strain and the newly sequenced SD90e low-passage-number clinical isolate strain, each from a different geographical area. In this study, we report the nearly complete genome sequences of 34 HSV-2 low-passage-number and laboratory strains, 14 of which were collected in Uganda, 1 in South Africa, 11 in the United States, and 8 in Japan. Our analyses of these genomes demonstrated remarkable sequence conservation, regardless of geographic origin, with the maximum nucleotide divergence between strains being 0.4% across the genome. In contrast, prior studies indicated that HSV-1 genomes exhibit more sequence diversity, as well as geographical clustering. Additionally, unlike HSV-1, little viral recombination between HSV-2 strains could be substantiated. These results are interpreted in light of HSV-2 evolution, epidemiology, and pathogenesis. Finally, the newly generated sequences more closely resemble the low-passage-number SD90e than HG52, supporting the use of the former as the new reference genome of HSV-2. Herpes simplex virus 2 (HSV-2) is a causative agent of genital and neonatal herpes. Therefore, knowledge of its DNA genome and genetic variability is central to preventing and treating genital herpes. However, only two full-length HSV-2 genomes have been reported. In this study, we sequenced 34 additional HSV-2 low-passage-number and laboratory viral genomes and initiated analysis of the genetic diversity of HSV-2 strains from around the world. The analysis of these genomes will facilitate research aimed at vaccine development, diagnosis, and the evaluation of clinical manifestations and transmission of HSV-2. This information will also contribute to our understanding of HSV evolution.

Simultaneous titration and phenotypic antiviral drug susceptibility testing for herpes simplex virus 1 and 2

BackgroundMost herpes simplex virus (HSV) isolates from treatment-naïve patients are susceptible to antivirals. However, prolonged antiviral therapy can select for drug-resistant strains, especially in immunocompromised patients. Standard phenotypic methods for antiviral resistance testing are labor and time-intense and molecular resistance determinants are insufficiently understood for routine diagnostic use of genotypic resistance testing. ObjectiveTo enable rapid, scalable antiviral susceptibility testing and minimize viral passage, we developed a 7-day, 96-well assay for simultaneous HSV 1/2 titration and phenotypic resistance testing for acyclovir and foscarnet. Study designThe assay was optimized and validated by testing clinical isolates and laboratory strains (n=39) with known IC50 for acyclovir (23 resistant) and foscarnet (1 resistant) based on plaque reduction or dye-uptake assays. A chemiluminescent detection reagent is used for quantification of cytopathic effect instead of plaque counting or measuring dye-uptake. Drug concentrations inhibiting 50% of chemiluminescent signal reduction (IC50) were determined concurrently at each of three virus dilutions. ResultsResults agree for 92.3% (acyclovir) and 100% (foscarnet) of isolates. For all three discordant samples, results of reference testing by plaque reduction agreed with the chemiluminescent assay. Reproducibility studies showed 100% qualitative agreement and 3–37% coefficient of variation based on IC50. ConclusionsChemiluminescence detection as a surrogate for cellular viability with an automated plate reader provides improved throughput and workflow, as well as high accuracy and reproducibility for antiviral drug susceptibility testing.

Herpes simplex virus: isolation, cytopathological characterization and antiviral sensitivity.

BACKGROUND Herpes simplex virus (HSV) infection is an endemic disease and it is estimated that 6095% of the adult population are infected with symptoms that are usually self-limiting, though they can be serious, extensive and prolonged in immunocompromised individuals, highlighted by the emergence of drug-resistant strains. The study of the wild-type HSV strains based on the cytopathogenic features and its antiviral sensitivity are important in the establishment of an antivirogram for controlling the infection.OBJECTIVE This study sought to isolate and examine the cytopathological characteristics of circulating strains of the Herpes simplex virus, from clinical specimens and their sensitivity to commercially available antiherpesvirus drugs, acyclovir, phosphonophormic acid and trifluridine.METHODS Herpes simplex virus isolation, cytopathological features and antiviral sensitivity assays were performed in cell culture by tissue culture infectious dose or plaque forming unit assay.RESULTS From twenty-two clinical specimens, we isolated and adapted nine strains. Overall, the cytopathic effect was detected 24 h post-infection (p.i.) and the presence of syncytia was remarkable 48 h p.i., observed after cell staining. Out of eight isolates, four developed plaques of varying sizes. All the isolates were sensitive to acyclovir, phosphonophormic and trifluridine, with the percentage of virus inhibition (%VI) ranging from 49.7-100%.CONCLUSIONSThe methodology for HSV isolation and characterization is a straightforward approach, but the drug sensitivity test, regarded as being of great practical importance, needs to be better understood.

Evaluation of anti-infective potential of a tribal folklore Odina wodier Roxb against some selected microbes and herpes simplex virus associated with skin infection

To evaluate the in vitro antimicrobial activity of aqueous and methanol extracts of Odina wodier bark (OWB), a folk medicine, against representative bacteria, fungi and herpes simplex virus (HSV) associated with skin infections. The OWB extract(s) was found to inhibit the isolates of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli at an MIC of 256-5000μgml(-1) and Candida albicans at and above 4000μgml(-1) by agar and broth dilution assays. The growth curve of Staph.aureus revealed the highest activity within 2-6h of methanol extract (ME) exposure. Interestingly, the MTT and plaque reduction assay showed that the extracts can inhibit HSV-1 and HSV-2 at EC50 of 22·4 and 28·8μgml(-1) , with Selectivity index of 11·7-15. While the time kinetic and binding assays demonstrated that the ME at 50μgml(-1) prevents viral attachment into Vero cells. Phytochemical and HPLC analysis of ME revealed the presence of flavonoids, phytosterols, saponins and tannins including the pseudotannin chlorogenic acid. The traditional use of OWB for the management of skin infections has scientific basis. This study demonstrated the antimicrobial potential of OWB on selected isolates of bacteria, fungi and HSV, associated with skin infections.

Ganciclovir, Foscarnet, and Cidofovir: Antiviral Drugs Not Just for Cytomegalovirus.

A child who received a second bone marrow transplant 3 weeks ago as part of treatment for relapsed leukemia has developed fever along with low grade mucositis. The child has been on an acyclovir prophylaxis regimen. Viral culture of an oral specimen has grown herpes simplex virus (HSV) type 1. Serum quantitative polymerase chain reaction tests for cytomegalovirus (CMV) show a 2-log increase in viral load after onset of fever compared with 2 weeks prior. The Hematology-Oncology fellow who calls you for a consult expresses that, in addition to the CMV issue, there is concern that the HSV isolate may be resistant to acyclovir.

Clinical correlates of herpes simplex virus type 1 loads in the lower respiratory tract of critically ill patients

BackgroundThe significance of isolation of herpes simplex virus (HSV) type 1 from the lower respiratory tract in critically ill patients on mechanical ventilation is still unclear. In the current study, we used polymerase chain reaction techniques to quantify HSV-1 to further evaluate its role. ObjectivesThe hypothesis was that high loads reflect invasive pulmonary disease related to prolonged mechanical ventilation and increased mortality, as opposed to shedding from the upper respiratory tract, which leads to lower viral loads. Study designWe prospectively studied 77 consecutive patients admitted to the intensive care unit and analyzed 136 tracheal aspirates or bronchoalveolar lavage fluids, taken when clinically indicated in the diagnostic workup of fever, radiologic pulmonary infiltrates, progressive respiratory insufficiency or combinations. Samples were cultured for bacteria and yeasts according to routine microbiological methods and HSV-1 loads were determined by real time quantitative PCR. Viral loads were expressed per number of cells recovered. ResultsHSV-1 load was directly related to the simplified acute physiology score II (rs=0.47, P=0.04) when the first specimen taken proved positive for HSV-1. HSV-1 positivity concurred with Candida spp. colonization. Patients with and without a HSV-1 load did not differ with respect to pulmonary and systemic courses and vital outcomes. ConclusionsThe data suggest that HSV-1 in the lower respiratory tract originates from shedding in the upper respiratory tract in about 30% of critically ill patients, following immune suppression and reactivation, without invasively infecting the lung. No attributable mortality was observed.

Overcoming drug-resistant herpes simplex virus (HSV) infection by a humanized antibody

Despite the availability of antiviral chemotherapy, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections remain a severe global health problem. Of particular concern is the growing incidence of drug resistance in immunocompromised patients, which stresses the urgency to develop new effective treatment alternatives. We have developed a humanized monoclonal antibody (mAb hu2c) that completely abrogates viral cell-to-cell spread, a key mechanism by which HSV-1/2 escapes humoral immune surveillance. Moreover, mAb hu2c neutralized HSV fully independent of complement and/or immune effector cell recruitment in a highly efficient manner. Prophylactic and therapeutic administration of mAb hu2c completely prevented infection-related mortality of severely immunodeficient mice being challenged with a lethal dose of HSV-1. The high neutralization capacity of mAb hu2c was fully maintained toward clinical HSV isolates being multiresistant to standard antiviral drugs, and infection was fully resolved in 7/8 nonobese diabetic/SCID mice being infected with a multidrug resistant HSV-1 patient isolate. Immunohistochemical studies revealed no significant cross-reactivity of the antibody toward human tissues. These features warrant further clinical development of mAb hu2c as an immunotherapeutic compound for the management of severe and particularly drug-resistant HSV infections.

Heterogeneity and Evolution of Thymidine Kinase and DNA Polymerase Mutants of Herpes Simplex Virus Type 1: Implications for Antiviral Therapy

Infections caused by acyclovir-resistant isolates of herpes simplex virus (HSV) after hematopoietic stem cell transplantation (HSCT) are an emerging concern. An understanding of the evolutionary aspects of HSV infection is crucial to the design of effective therapeutic and control strategies. Eight sequential HSV-1 isolates were recovered from an HSCT patient who suffered from recurrent herpetic gingivostomatitis and was treated alternatively with acyclovir, ganciclovir, and foscavir. The diverse spectra and temporal changes of HSV drug resistance were determined phenotypically (drug-resistance profiling) and genotypically (sequencing of the viral thymidine kinase and DNA polymerase genes). Analysis of 60 clones recovered from the different isolates demonstrated that most of these isolates were heterogeneous mixtures of variants, indicating the simultaneous infection with different drug-resistant viruses. The phenotype/genotype of several clones associated with resistance to acyclovir and/or foscavir were identified. Two novel mutations (E798K and I922T) in the viral DNA polymerase could be linked to drug resistance. The heterogeneity within the viral populations and the temporal changes of drug-resistant viruses found in this HSCT recipient were remarkable, showing a rapid evolution of HSV-1. Drug-resistance surveillance is highly recommended among immunocompromised patients to manage the clinical syndrome and to avoid the emergence of multidrug-resistant isolates.

Herpes Simplex Virus Duodenitis Accompanying Crohn's Disease

Herpes simplex virus (HSV) is a recognized cause of gastrointestinal infection in immunodeficient patients. Although a few cases of HSV gastritis and colitis in immunocompromised patients have been reported, there are no reports of HSV duodenitis in patients with Crohn's disease (CD). A 74-year-old female was admitted with general weakness and refractory epigastric pain. She had been diagnosed with CD three years ago. Esophagogastroduodenoscopy (EGD) revealed diffuse edematous and whitish mucosa with multiple erosions in the duodenum. Considering the possibility of viral co-infection, cytomegalovirus (CMV) immunohistochemical staining, PCR, and cultures of duodenal biopsies were performed, all of which were negative with the exception of the isolation of HSV in culture. After administration of intravenous acyclovir for 1 week, follow-up EGD showed almost complete resolution of the lesions and the patient's symptoms improved. In CD patients with refractory gastro-intestinal symptoms, HSV, as well as CMV, should be considered as a possible cause of infection, so that the diagnosis of viral infection is not delayed and the appropriate antiviral treatment can be initiated.

Screening of herpes simplex virus type 1 isolates for acyclovir resistance using DiviTum® assay

Rapid alternative methods are required to evaluate easily acyclovir (ACV) sensitivity of clinical herpes simplex virus (HSV) isolates. The objective of this study was to screen 54 ACV-sensitive and 41 ACV-resistant clinical HSV-1 isolates, well characterized by phenotypic and genotypic methods, for the phosphorylation activity of the viral thymidine kinase (TK) using a commercially available and modified non-radioactive DiviTum® test on the basis of an indirect enzyme linked immunosorbent assay. The ACV-sensitive HSV-1 isolates had high TK activity values between 31.5±6.4 DiviTum® Units per liter (DU/L) and 487.4±60.1 DU/L. The mean activity of all ACV-sensitive isolates was calculated as 212.3±15.7 DU/L. By contrast, the mean activity of all ACV-resistant HSV-1 isolates was significantly lower at 5.5±1.3 DU/L. Out of the 41 ACV-resistant HSV-1 isolates, 38 had no or very low phosphorylation activities of the viral TK between 0 DU/L and 9.3±3.2 DU/L. The remaining three ACV-resistant viral isolates had TK activities between 44.6±5.1 DU/L and 80.9±13.3D U/L. In conclusion, the modified DiviTum® test can be used to screen HSV-1 isolates for their sensitivity to ACV. Acyclovir-sensitive HSV-1 isolates show TK activities >30 DU/L and ACV-resistant isolates have activity values <10 DU/L. However, single ACV-resistant HSV-1 isolates can have TK activity values >30 DU/L. These strains are most likely ACV-resistant TK-altered mutants, but no evidence was provided for an alteration of the TK.

Possible antiviral activity of montelukast against Herpes Simplex Virus type-1 and Human Adeno Virus in vitro

Montelukast (MLS) is used for the treatment of various allergic reactions. Viral infections are important, especially in exacerbation of allergic diseases. In this study, the apoptotic/necrotic responses of Herpes Simplex Virus (HSV-1 and Human Adenovirus (HAdV) isolate in HEp-2 and Vero cell cultures were compared with the presence or absence of non-toxic doses of pure MLS. The non-toxic dose of pure MLS for both cell lines was found to be 9.76 µg/ml. The apoptotic cell (APC) ratios of HEp-2 cells infected with HSV and HAdV were 12.5 and 9.1% before MLS and 10.3 and 7.7% after MLS, respectively. The necrotic cell (NEC) ratio of HEp-2 cells infected with HSV and HAdV were found to be 26 and 20% before MLS and were found to be 22.0 and 18.7% respectively after MLS. APC ratio of Vero cells infected with HSV and HAdV were found to be 16 and 12.85% before MLS and were found to be 14.6 and 10.4% respectively after MLS. NEC ratio of Vero cells infected with HSV and HAdV were found to be 34 and 28.2% before MLS and were found to be 30 and 26.4% respectively after MLS. The tissue culture infectious doses (TCID50) values of HSV-1 for HEp-2 cells and Vero cells without MLS were 10-5,25/0.1 ml and 10-4,95/0.1 ml, with MLS were 10-4,15/0.1 and 10-3,75/0.1 ml, respectively. The TCID50values of HAdV for HEp-2 cells and Vero cells without MLS were 10 -7,0/0.1 and 10-6,75/0.1 ml, with MLS were 10-6, 25/0.1 and 10-5, 75/0.1 ml, respectively. Although the methods applied in this study provides opportunities for morphologic diagnosis; results suggest the possible antiviral effect of montelukast. Key words: Montelukast, simplexvirus, adenoviridae, atopy, Vero cells, HEp-2 agents.

Efficacy of ASP2151, a helicase–primase inhibitor, against thymidine kinase-deficient herpes simplex virus type 2 infection in vitro and in vivo

ASP2151 was developed as a novel inhibitor of herpes simplex virus (HSV) and varicella-zoster virus helicase–primase. The anti-HSV activity of ASP2151 toward a clinical HSV isolate with acyclovir (ACV)-resistant/thymidine kinase (TK)-deficiency was characterized in vitro and in vivo using a plaque reduction assay and the ear pinna infection in mice. The IC50 ranged from 0.018 to 0.024μg/ml, indicating the susceptibility of TK-deficient HSV-2 was similar to that of wild-type HSV-2 strains. Anti-HSV activity of ASP2151 in vivo was evaluated in mice infected with wild-type HSV-2 and TK-deficient HSV-2. ASP2151 significantly reduced the copy numbers of wild-type HSV-2 and TK-deficient HSV-2 at the inoculation ear pinna, while valacyclovir significantly reduced the copy number of wild type HSV-2 but not that of TK-deficient HSV-2 in the inoculated ear pinna. Thus, ASP 2151 showed therapeutic efficacy in mice infected with both wild-type and TK-deficient HSV-2. In conclusion, ASP2151 is a promising novel herpes helicase–primase inhibitor that indicates the feasibility of ASP2151 for clinical application for the treatment of HSV infections, including ACV-resistant/TK-deficient HSV infection.