Exploring the Antiviral Potential of Tungsten Oxide Nanoparticles Against Herpes Simplex Virus Type 1: A Promising Alternative to Acyclovir

Introduction. Chronic and latent infections are often activated during pregnancy.Aim - to asses the pathogenetic role of microbial pathogens in urogenital tract infection (UTI) in pregnant women.Materials and methods. 89 pregnant women underwent general clinical examination, examination of smears from urethra, vagina, cervical canal; bacteriological analysis of vaginal contents; enzyme-linked immunosorbent assay, polymerase chain reaction and determination of specific antibodies for verification of herpes simplex virus (HSV) type I and II, cytomegalovirus (CMV), Epstein-Barr (EBV) and UTI pathogens in pregnant women in blood and mucosal scrapes.Results. Prevalence of Herpesviridae was revealed (90-100% -EBV, HSV type I and II, CMV); in 41% of cases - bacterial pathogens, in 57% of cases - Mycoplasma, Ureaplasma.Discussion. In preterm birth and pregnancy termination mycoplasma and ureaplasma were more often revealed, and in pregnancy termination - association of HSV type I and II in comparison with urgent birth; in the last equally often - HSV type I and association of HSV type I and II; in urgent birth (infection) more often - HSV type I, than association of HSV type I and II; in preterm birth more often - HSV type I, than the association of HSV types I and II, and less often than combination of HSV type I and association of HSV types I and II in pregnancy termination; in the last, the association of HSV types I and II is more common than HSV type I. Increase of TLRs genes expression levels depends on HSV type I less than from association of HSV types I and II, less than from combination of HSV type I and association of HSV types I and II (it determines the clinical manifestations of genital herpes).Conclusion. Microbial pathogens determine the character of pregnancy course, and HSV types I and II- are the triggers of the infectious process, prognosing its course.

Proanthocyanidin-enriched extract from Myrothamnus flabellifolia Welw. exerts antiviral activity against herpes simplex virus type 1 by inhibition of viral adsorption and penetration

Commentary on 'Fast anterograde transport of herpes simplex virus: role for the amyloid precursor protein of Alzheimer's disease' by Prasanna Satpute-Krishnan et al. Aging Cell Vol. 2, Issue 6, 305-318 (2003).

Differentiation of Herpes Simplex Virus Types 1 and 2 in Sera of Patients with HSV Central Nervous System Infections by Type-specific Enzyme-linked Immunosorbent Assay

Isolates from a total of 228 patients with clinical herpes simplex were included in this study: 92 were from patients in their first episode and 136 were from patients with recurrent genital herpes...

To evaluate the efficiency of 3 short hairpin RNA (shRNA) interfering with the herpes simplex virus type 1 (HSV-1) gene coding glycoprotein D (gD) for inhibiting the gD expression and virus replication in vitro. Vero cells were selected for an in vitro model of infection. Three shRNA sequences (shRNAgD1, -gD2, and -gD3) targeting specifically the gD gene of HSV-1 were selected for evaluating the antiviral effects. The antiviral effects of shRNA in the cells infected with HSV-1 were evaluated by cytopathic effect (CPE) observations and plaque assays. The transcription level of viral RNA and the gD expression were studied by RT-PCR, Western blotting, and flow cytometry. With the 3 shRNA at a final concentration of 120 nmol/L, a significant inhibition of CPE in the HSV-1-infected cells was observed. The ED50 of shRNA-gD1, gD2, and gD3 were 48.74+/-2.57, 57.13+/-3.24, and 114.64+/-5.12 nmol/L, respectively. The gD gene decreased significantly after viral infection in the Vero cells pretreated with shRNA compared to the virus group. The expressions of the gD protein, determined by Western blotting and flow cytometry, were also drastically decreased in shRNA-transfected cells. Exogenous shRNA molecules can suppress the HSV-1 gD expression. They are inhibitors of HSV replication during infection in Vero cells.

Functional Recovery in a Friedreich's Ataxia Mouse Model by Frataxin Gene Transfer Using an HSV-1 Amplicon Vector

To study the role of pathogenic microorganisms commonly associated with chronic eye disease, including Chlamydia psittaci, Chlamydia trachomatis, Chlamydia pneumoniae, herpes simplex virus (HSV) type 1 and type 2, and adenovirus type 8 and type 19, in the development of primary ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma in Chinese patients. Sixty-eight archival cases of primary ocular adnexal lymphoproliferative lesions, including 38 cases of MALT lymphoma, 3 cases of non-MALT lymphoma and 27 cases of chronic inflammation, were enrolled into the study. DNA was extracted from the paraffin-embedded tissue samples. The presence of DNA of C. psittaci, C. trachomatis, C. pneumoniae, HSV type 1, HSV type 2, adenovirus type 8 and adenovirus type 19 were analyzed by multiplex touchdown enzyme time-release polymerase chain reaction (TETR-PCR). All of the specimens yielded PCR products of over 100 base pairs and were thus suitable for TETR-PCR screening of infectious agents. The prevalence of DNA of C. psittaci, C. trachomatis and adenovirus type 19 were 0 in MALT lymphoma, non-MALT lymphoma and chronic inflammation. There were 2 cases positive for C. pneumoniae DNA, amongst the 38 cases of MALT lymphoma studied (5.3%, 2/38). HSV type 1, HSV type 2 and adenovirus type 8 DNA was found in each of the 3 patients with chronic inflammation. The study indicates that C. psittaci, C. trachomatis, C. pneumoniae, HSV type 1, HSV type 2, adenovirus type 8 and adenovirus type 19 probably play little role in the pathogenesis of ocular adnexal MALT lymphoma in Chinese patients.

With data supporting the use of suppressive antiviral therapy to reduce transmission of herpes simplex virus (HSV) between discordant couples (1), and with the availability of more sensitive and specific serological assays, there has been increasing emphasis on accurate diagnosis of HSV infection in an effort to control the genital herpes epidemic. In this issue of The Canadian Journal of Infectious Diseases & Medical Microbiology, Ratnam et al (2) review herpes diagnostics and make suggestions for their use by Canadian clinicians. Clearly, virus isolation or detection of HSV type 1 (HSV-1) or HSV type 2 (HSV-2) viral DNA by molecular methods, such as polymerase chain reaction (PCR) from a genital lesion, is diagnostic of genital herpes. The speed and enhanced sensitivity of PCR compared with culture make it the test of choice for the diagnosis of active disease (3). Although PCR can detect asymptomatic shedding, viral detection tests are generally only of value when genital lesions are present. In the absence of lesions, some experts have suggested the use of type-specific serology (TSS) to identify individuals who are infected with HSV. The rationale for serological testing is to identify asymptomatic HSV infection. Until recently, HSV serology was unhelpful because it could not accurately differentiate antibodies to HSV-2 (almost exclusively as a result of genital herpes) from HSV-1 (predominantly generated in response to an orolabial infection). HSV TSS uses commercially available tests that have the ability to accurately differentiate or ‘type’ antibody responses generated by HSV-1 from HSV-2 infection. However, interpretation of the results requires an understanding of the performance characteristics of the test, as well as the prevalence of the infection in the population in which testing is being applied. What does a positive HSV TSS mean? There are data to suggest that knowledge of an individual's HSV-2 status can allow for disclosure and implementation of suppressive antiviral therapy to reduce the risk of transmission to partners (1,4). Certainly, a positive HSV-2 result generally equates to a diagnosis of genital herpes. However, because specificity of TSS is not 100%, false-positive results will occur. For example, when used in pregnant women, the HerpeSelect-2 kit (Focus Technologies, USA) has a specificity of 96%, which means that of every 100 positive tests, four of these will be falsely positive (Table 1, Ratnam et al). If the overall prevalence of HSV-2 antibodies in pregnant women in Newfoundland and Labrador is 6%, the positive predictive value (PPV) of this test is only 61%. Can a PPV of 61% allow a physician to confidently say that the patient is infected with HSV-2 and no longer at risk for primary infection? Conversely, a negative HSV-2 result does not rule out the diagnosis of genital herpes because the patient may have an HSV-1 infection to account for symptoms. In fact, as acknowledged by Ratnam et al, there is an increasing prevalence of HSV-1 as the cause of genital herpes in some regions of the country. In Nova Scotia, the majority of genital swabs in young people are positive for HSV-1, not HSV-2. However, what does a positive HSV-1 serology result mean? This may represent an orolabial infection, and not genital herpes at all. The absence of a history of cold sores is unhelpful because as with genital infections, many people who have orolabial infections are unaware that they have been infected. Differentiation of these two possibilities is often impossible, making a positive HSV-1 result unhelpful. Ratnam et al suggest that a positive result provides the opportunity for counselling regarding transmission via oral and genital sex. However, if the patient has HSV-1 antibodies generated by orolabial HSV-1 infection, to suggest that these antibodies protect them from subsequent HSV-1 genital infection may not be completely accurate. Instances of autoinoculation of HSV-1 from an orolabial lesion to the genitals suggest that the antibodies are not completely protective. Thus, how does this knowledge of HSV serostatus change the patient's counselling or management? While the recommendations on the use of serological tests focus on selective populations thought to benefit the most from serodiagnosis, how exactly these tests should be used remains controversial (5–12). Although Ratnam et al have provided a comprehensive review of the literature on HSV TSS, a number of recommendations merit further consideration. Ratnam et al suggest that “TSS should be performed or repeated on specimens collected at least six weeks after exposure to ensure that the antibody response has occurred”. However, it is unclear what is to be considered an exposure. Because the prevalence of HSV-2 in many areas may be 20% and for HSV-1 it could be 50% to 80% (13), there is a one in five chance that unprotected intercourse, or a greater than one in two chance that oral sex, with any new partner would equate to HSV exposure. Given that infected individuals only shed the virus intermittently, the risk would obviously not be this high. However, it is unclear what the risk of acquiring HSV is from one sexual encounter or how many people would need to be screened to diagnose one infection. Ratnam et al also suggest that HSV-2 TSS be offered to those diagnosed with HIV, a measure that “could provide the opportunity to improve health outcome and also serve as an adjunct to risk-reduction counselling”. The prevalence of HSV-2 in HIV-infected individuals is indeed higher than the general population and, thus, the PPV of the test will be higher (13). Data also suggest that HSV-2 facilitates the acquisition of HIV and that suppression of HSV can reduce the HIV viral load, potentially reducing the risk of transmission of HIV (14–16). Chronic suppressive therapy using daily valacyclovir has been shown to decrease plasma and genital levels of HIV RNA in women dually infected with HSV-2 and HIV (16). However, whether knowledge of patients’ HSV serostatus translates into adopting risk-reduction strategies is unclear and unproven. For example, if an HIV-infected patient has not modified behaviours on the basis of his or her HIV status, is it realistic to expect that the documentation of HSV-2 infection would yield behavioural changes? In regard to offering HSV TSS testing as an opportunity to improve the health of HIV-infected individuals, I would speculate that the majority of those in whom HSV-2 infection has had a significant negative impact have identifiable outbreaks that can be diagnosed with molecular methods. There is no indication for treatment of asymptomatic HSV in persons with HIV. In fact, HSV-suppressive therapy with acyclovir in immunosuppressed individuals is associated with higher rates of resistance than in those who are immunocompetent (17). Thus, it warrants consideration that suppressive therapy in an immunosuppressed, asymptomatic individual may not be reasonable and in the long-term, could be harmful. Ratnam et al have put together a comprehensive and timely review. However, multiple issues need consideration when choosing a test and interpreting its result. With any diagnostic test, the prevalence of the disease in the population is essential to interpreting the test result. Clinicians need to be aware of the test limitations and need to consider whether the results influence the treatment or outcome. If the results do not influence the outcomes or management, then testing is a waste of finite health resources and is not indicated. We must also ensure that the reason for ordering the test is evidence-based and not driven by marketing campaigns. Fundamentally, I see guidelines as an important way to standardize and ensure appropriate testing. Although I understand the basis for the recommendations made by Ratnam et al, I still struggle with identifying where HSV TSS fits into the diagnostic armamentarium of HSV infection; discussions with other clinicians suggest that I am not alone. In the clinical laboratory, we do not reliably get clinical information to help guide decisions on whether the test requested is appropriate. I am unsure how useful HSV TSS would be in the population my laboratory serves, in which the prevalence of genital infection due to HSV-1 is higher than that of HSV-2. A cost-effectiveness analysis taking into consideration the increased costs of testing, the cost of the subsequent interventions (suppressive therapy) and whether the testing influences outcomes needs to be considered if these suggestions are translated into public health policy. My apprehension is that HSV TSS will start in select circumstances but slip into broader practice without the appropriate evidence or cost-benefit analysis to support its use until it becomes a part of routine screening of asymptomatic patients presenting for a sexual health check up or even as a regular part of the annual medical examination.

Purpose. Herpes simplex virus type 1 (HSV-1) infects the cornea possibly causing blindness. The specific mechanisms of herpetic keratitis are unclear. We aimed to investigate whether HSV-1 would up- or down-regulate the apoptotic pathway of human corneal epithelial (HCE) cells. Methods. HSV-1 infection of HCE and Vero cells was demonstrated (immunofluorescence) and apoptotic gene expression was quantified (ribonuclease protection assay). Caspase 8 protein activity (colorimetric assay) was quantified and compared to caspase 8 mRNA amounts from RPA experiments. The apoptotic index of HSV-1 infected HCE and Vero cells (apoptotic index = % of apoptotic cells in infected samples/mock treated samples) was obtained and compared to gene expression. Results. A down-regulation in apoptotic gene expression was observed in HSV-1 infected HCE cells in contrast to Vero cells (infected and mock treated). Caspase 8 protein levels mirrored caspase 8 mRNA levels in HSV-1 infected HCE cells. The apoptotic index also supports this down-regulation. HSV-1 infected human corneal epithelial cells and Vero cells at similar rates. Conclusions. HSV-1 down-regulates the apoptotic pathway of human corneal epithelial cells. This down-regulation of apoptotic gene expression seems to be cell specific. Also infectivity is excluded in playing a role in regulation of the apoptotic pathway because HSV-1 replicated at similar rates in HCE and Vero cells.

Herpes simplex virus type 1 (HSV-1) and pseudorabies virus (PRV) infect different natural hosts but are very similar in structure, replicative cycle, and entry into cultured cells. We determined whether HSV-1 and PRV use the same cellular components during entry into Vero cells, which are highly susceptible to each virus but are not from native hosts for either. UV-inactivated virions of either HSV-1 or PRV could saturate cell surfaces to block infection of challenge HSV-1 or PRV. In the presence of saturating levels for infection of either virus, radiolabeled virus bound well and in a heparin-sensitive manner. This result shows that heparan sulfate proteoglycans on Vero cells are not the limiting cellular component. To identify the virus component required for blocking, we used an HSV-1 null mutant virus lacking gB, gD, or gH as blocking virus. Virions lacking gB were able to block infection of challenge virus to the same level as did virus containing gB. In contrast, virions lacking gD lost all and most of the ability to block infection of HSV-1 and PRV, respectively. HSV-1 lacking gH and PRV lacking gp50 also were less competent in blocking infection of challenge virus. We conclude that HSV-1 and PRV bind to a common receptor for infection of Vero cells. Although both viruses bind a heparin-like cell component on many cells, including Vero cells, they also attach to a different and limited cell surface component that is bound at least by HSV-1 gD and possibly gH and to some degree by PRV gp50 but not gB. These results clearly demonstrate binding of both HSV-1 and PRV to a common cell receptor that is not heparan sulfate and demonstrate that several types of attachment occur for both viruses during infectious entry.

Background: The epidemiology of human papillomavirus (HPV) and co-infections with herpes simplex virus type 2 (HSV-2) remains poorly characterized in Africa. High risk HPV (hrHPV) infection is the primary cause of 99.7% all cervical cancer especially in the presence of genital ulcer disease (GUD) which is usually caused by HSV-2. Herpes simplex virus-2 might interact directly with hrHPV to increase the risk of cervical cancer. Co-infection of HPV and HSV-2 in asymptomatic women could provide a clue to early diagnosis of cervical cancer and this could aid in the development of new strategies for effective management and improvement of the quality of life of women who are infected. If the synergy between HPV and HSV-2 can be prevented, there may be significant reduction of the incidence of cervical cancer. Methodology: This was a descriptive cross-sectional study of 515 randomly selected apparently healthy women of reproductive age whose cervical samples were screened for HPV and HSV-2 in Kaduna State, Nigeria. The cervical samples were collected by liquid-based cytology (LBC) for detection of cervical epithelial cell abnormalities (CEA) and molecular detection of HPV and HSV-2 using conventional polymerase chain reaction (PCR) assay. Extracted viral DNAs from the samples were amplified by convectional PCR using specific hrHPV (HPV 16,18, 31 and 45) primer sets and a broad spectrum MY09/11 and GP5+/6+ primers for a wider range of HPV genotypes while HSV-2 DNA was detected by florescence-based PCR assay with HSV-2 gG primers and probes. Results: PCR assay revealed that 14.7% (n=76) of the 515 selected women harbored HPV, HSV-2 or both. The prevalence of HPV, hrHPV, HSV-2 and HPV/HSV-2 co-infection among in the study participants are 11.8% (n=61), 9.3% (n=48), 5.6% 4% (n=29) and 2.3% (n=12) respectively. The frequency of HPV detection in HSV-2 infected participants (41.4%, 12/29) was significantly higher (OR=6.295, p<0.0001) than in HSV-2 negative participants (10.1%, 49/437), but only co-infections of HPV-31 (p=0.004) and HPV-18 (p=0.040) with HSV-2 were significantly associated. Cervical cytology reports on the smears revealed prevalence of cervical epithelial abnormalities (CEA) of 16.7% (n=86), with cervical dysplasia prevalence of 6.4% (n=33), consisting of high grade squamous intraepithelial lesion (HGSIL) of 1.6% (n=8), low grade squamous intraepithelial lesion (LGSIL) of 4.1% (n=21) and atypical squamous cells of uncertain significance (ASCUS) of 0.8% (n=4). The frequency of HPV detection in women with cervical dysplasia (93.9%, 31/33) was significantly higher (OR=14.22, p<0.0001) than in women without cervical dysplasia (6.2%, 30/482), and all HPV genotypes were significantly associated (p<0.05) with cervical dysplasia except HPV 16 (p=0.051). Also, the frequency of HPV/HSV-2 co-infection among women with cervical dysplasia (15.2%, 5/33) was significantly higher than among women without cervical dysplasia (1.5%, 7/482) (OR=12.12, p<0.0001). Comparing women with cervical inflammatory and atrophic changes (n=53), women with cervical dysplasia (HGSIL, LGSIL and ASC-US) had significantly higher frequency of HPV infection (χ2=42.829, p=0.000), HSV-2 infection (χ2=25.140, p=0.001) and HPV/HSV-2 co-infections (χ2=66.602, p=0.000). Conclusion: Co-infection rate of hrHPV and HSV-2 among women in Kaduna State is 2.3%. Demographic factors significantly influencing the rate of co-infections included age and marital status. In spite of the screening method using the traditional Pap smear, GUD and cervical cancer continues to be a major public health problem, thus more sensitive and specific methods such as liquid based cytology technique and polymerase chain reaction for early detection of cervical dysplasia and hrHPV or HSV-2 in asymptomatic women should be adopted for routine use

Background and Aims: Herpes simplex virus Type 1 (HSV-1) causes a wide spectrum of diseases in humans, including skin and mucosal ulcers, encephalitis, and keratitis. Acyclovir is regarded as the gold standard for treating infections with this virus. However, there are certain drawbacks to using this drug, such as its ineffectiveness against treatment-resistant virus strains. Therefore, the development of novel and effective drugs to combat this virus is urgently needed. The present work aims to explore the efficacy of magnesium oxide nanoparticles (MgONPs) against HSV-1 in vitro as a potential novel antiviral agent.Methods: MgONPs were characterized by X-ray diffraction, energy-dispersive X-ray spectroscopy, field-emission scanning electron microscope, ultraviolet-visible spectrophotometry, Fourier-transform infrared spectroscopy, dynamic light scattering, and zeta potential. To assess the cytotoxic effects of MgONPs on Vero cells, the neutral red uptake assay was used. The effects of MgONPs at nontoxic concentrations on HSV-1 were then examined using a quantitative real-time PCR assay.Results: No toxic effect was observed in all used concentrations of MgONPs (up to a concentration of 1000 μg/mL). Three-hour incubation of HSV-1 with MgONPs at concentrations of 900 and 1000 μg/mL resulted in a remarkable decrease in viral load with an inhibition rate of 93.6% and 96.8%, respectively. The results from the posttreatment assay also showed that MgONPs at concentrations of 300 and 1000 μg/mL led to a significant decrease in viral load with an inhibition rate of 99.5% and 99.7%, respectively.Conclusion: MgONPs can exert their inhibitory effects on HSV-1 in a dose-dependent manner, both directly and through interfering with the replication cycle of the virus.

Sea cucumber has antiviral activities against various viruses including herpes simplex virus type 1 (HSV-1). The purpose of the current study was to determine the chemical profile and inhibitory effects of tegument ethanolic extract of Holothuria parva on HSV-1 infection and to elucidate the mechanism of antiviral action of this marine invertebrate. Cytotoxic activity of the extract on Vero cell line was determined using the methyl thiazolyl tetrazolium (MTT) method. The different components in H. parva were determined by GC-MS analysis. To assess the antiviral activity of the extract, MTT and 50% tissue culture infective dose (TCID50) were applied. Finally, computational molecular docking was performed to screen the potential binding ability of extract contents with HSV-1 surface glycoproteins and host cell surface receptors. Using MTT assay, the non-cytotoxic concentration of the extract was measured 46.5 μg/mL. Octadecanoic acid 2-hydroxy-1-(hydroxymethyl) ethyl ester and 2′,6′-acetoxylidide were two major constituents in the H. parva extract. Pre-treatment of HSV-1 with the ethanolic extract of H. parva led to a 2.1 log10 TCID50 reduction in virus titers when compared to the control group (P = 0.002). The log10 TCID50 reductions relative to the control group for co-penetration and post-penetration assays were 1.5 (P = 0.009) and 0.7 (P = 0.09), respectively. The tegument ethanolic extract of H. parva has significant antiviral properties against HSV-1. Docking analysis demonstrated that compounds of the extract [lidocaine and 2-hydroxy-1-(hydroxymethyl) ethyl ester octadecanoic acid] may cover similarly both virus and host cells binding domains leading to interference in virus attachment to cell receptors.

Objective To evaluate the anti- herpes simplex virus type 1 (HSV-1) activity of KPC-rg1, a water extract from Cinnamomum cassia, and explore its potential function of broad-spectrum antivirus effect. Methods In vitro, the changes of morphology of Vero cells were assessed and viral loads were detected after cells were infected with HSV-1 alone and HSV-1 pre-treated with KPC-rg1 respectively. The corneal lesions of mouse and tree shrew corneal infection model were evaluated after they were infected with HSV-1 alone and HSV-1 pre-treated with KPC-rg1 respectively. The antiviral activity of KPC-rg1 against 9 viruses were measured by CPE and GFP reduction assays. Results The virus replication of HSV-1 infected cells was moderately inhibited by KPC-rg1 in a dose range of 0.0001-1.0 mg/ml, while the cells were completely protected when they were infected with HSV-1 pre-treated with KPC-rg1 (0.001-1.0 mg/ml). The corneal lesions of animals were improved in both mouse and tree shrews models infected with HSV-1 after the treatment of KPC-rg1, while animals were completely protected from infection when HSV-1 pre-treated with KPC-rg1. KPC-rg1 had a potential anti-virus effect on the enveloped viruses such as HSV-1, HCMV, RSV alone and HIV-1. Conclusions KPC-rg1 is a collosol (Tyndall effect) which would immediately form a stable super-nanoparticle structure of KPC-rg1/virus when encounter virus, and thus the virus coated by KPC-rg1 lost its ability of infection. KPC-rg1 can reduce the suffering by newly or latent virus infection because its encapsulation of virus and inhibition of further infection. Our study added additional proofs of the anti-viral property of the water extract from Cinnamomum cassia, and provided a further basis to develop KPC-rg1 as a drug which could be potentially applied in clinic to treat HSV-1 infection. Key words: Cinnamon water extract KPC-rg1; Herpes simplex virus type 1; Antiviral activity