Susceptibility Evaluation of Clinically Isolated HSV-1 Strains to Acyclovir: A Phenotypic and Genotypic Study

Background: Mutations in herpes simplex virus Thymidine kinase (TK, UL23) and DNA polymerase (pol, UL30) genes may confer resistance to acyclovir (ACV). Phenotypic resistance must be determined along with genotypic resistance to achieve complete acyclovir susceptibility. Objectives: The present study aimed to characterize HSV-1 clinical isolates from outpatients and organ transplant recipients in terms of phenotypic ACV resistance. Moreover, genotypic resistance to ACV was assessed through sequencing the viral TK and pol genes amplified from virus-infected cell DNA. Methods: Twenty-six HSV-1 clinical isolates collected between 2016 and 2019 were examined for drug susceptibility. The samples were collected from eyes, oropharyngeal, facial, and other skin parts of immunocompetent and immunocompromised individuals. Phenotypic susceptibility was determined by using three different concentrations of ACV. The results were expressed based on the ability of ACV in reducing viral plaques by 50%. Genotyping was carried out by polymerase chain reaction and sequencing of TK and pol genes. Results: All the strains were characterized as sensitive at 0.01 and 0.05 µg.ml-1 concentrations to ACV. Seventy percent inhibition was observed at 0.1 mg/mL of ACV for three isolates (two from patients who received transplants and one from an outpatient). Nine natural polymorphisms were detected in the TK gene and 31 in the Pol gene. Furthermore, four susceptible-associated mutations in the DNA pol gene were analyzed. A substitution was encoded in the conserved region of the pol Exo III motif (M553L), and nine amino acid substitutions in TK were detected. The phylogenetic analysis of partial genome sequences revealed high diversity in the TK and pol genes of HSV-1. Conclusions: A higher number of mutations were observed in patients who received transplants and underwent long-term treatment compared with outpatients. The high genetic variability of HSV-1 TK and DNA pol was not associated with phenotypic resistance.

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Variability of the Glycoprotein G Gene in Clinical Isolates of Herpes Simplex Virus Type 1

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.6.6.826-831.1999 ◽

1999 ◽

Vol 6 (6) ◽

pp. 826-831 ◽

Cited By ~ 12

Author(s):

Elham Rekabdar ◽

Petra Tunbäck ◽

Jan-Åke Liljeqvist ◽

Tomas Bergström

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Herpes Simplex Virus Type ◽

Clinical Isolates ◽

Missense Mutations ◽

Sequence Variability ◽

Glycoprotein G ◽

Simplex Virus ◽

Hsv 1

ABSTRACT Glycoprotein G (gG) of herpes simplex virus type 1 (HSV-1) has been used as a prototype antigen for HSV-1 type-specific serodiagnosis, but data on the sequence variability of the gene coding for this protein in wild-type strains are lacking. In this study, direct DNA sequencing of the gG-1 genes from PCR products was performed with clinical HSV-1 isolates from 11 subjects as well as with strains Syn 17+, F, and KOS 321. The reference strains Syn 17+ and F showed a high degree of conservation, while KOS 321 carried 13 missense mutations and, in addition, 12 silent mutations. Three clinical isolates showed mutations leading to amino acid alterations: one had a mutation of K122 to N, which is a gG-1–to–gG-2 alteration; another contained all mutations which were observed in KOS 321 except two silent mutations; and the third isolate carried five missense mutations. Two clinical isolates as well as strain KOS 321 showed a mutation (F111→V) within the epitope of a gG-1-reactive monoclonal antibody (MAb). When all viruses were tested for reactivity with the anti-gG-1 MAb, the three strains with the F111→V mutation were found to be unreactive. Furthermore, gG-1 antibodies purified from sera from the two patients carrying strains mutated in this epitope were less reactive when they were tested by an HSV-1-infected-cell assay. Therefore, our finding that the sequence variability of the gG-1 gene also affects B-cell epitope regions of this protein in clinical isolates may have consequences for the use of this protein as a type-specific antigen for serodiagnosis.

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Antiherpesvirus Activities of (1′S,2′R)-9-{[1′,2′-Bis(hydroxymethyl)cycloprop-1′-yl]methyl}guanine (A-5021) in Cell Culture

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.7.1666 ◽

1998 ◽

Vol 42 (7) ◽

pp. 1666-1670 ◽

Cited By ~ 28

Author(s):

Satoshi Iwayama ◽

Nobukazu Ono ◽

Yuko Ohmura ◽

Katsuya Suzuki ◽

Miho Aoki ◽

...

Keyword(s):

Antiviral Agent ◽

Inhibitory Effect ◽

Clinical Isolates ◽

Human Embryonic Lung ◽

Growth Inhibition Assay ◽

Varicella Zoster ◽

Hel Cells ◽

Simplex Virus ◽

Short Time ◽

Hsv 1

ABSTRACT Antiherpetic activity of (1′S,2′R)-9-{[1′,2′-bis(hydroxymethyl)cycloprop-1′-yl]methyl}guanine (A-5021) was compared with those of acyclovir (ACV) and penciclovir (PCV) in cell cultures. In a plaque reduction assay using a selection of human cells, A-5021 showed the most potent activity in all cells. Against clinical isolates of herpes simplex virus type 1 (HSV-1,n = 5) and type 2 (HSV-2, n = 6), mean 50% inhibitory concentrations (IC50s) for A-5021 were 0.013 and 0.15 μg/ml, respectively, in MRC-5 cells. Corresponding IC50s for ACV were 0.22 and 0.30 μg/ml, and those for PCV were 0.84 and 1.5 μg/ml, respectively. Against clinical isolates of varicella-zoster virus (VZV, n = 5), mean IC50s for A-5021, ACV, and PCV were 0.77, 5.2, and 14 μg/ml, respectively, in human embryonic lung (HEL) cells. A-5021 showed considerably more prolonged antiviral activity than ACV when infected cells were treated for a short time. The selectivity index, the ratio of 50% cytotoxic concentration to IC50, of A-5021 was superior to those of ACV and PCV for HSV-1 and almost comparable for HSV-2 and VZV. In a growth inhibition assay of murine granulocyte-macrophage progenitor cells, A-5021 showed the least inhibitory effect of the three compounds. These results show that A-5021 is a potent and selective antiviral agent against HSV-1, HSV-2, and VZV.

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Susceptibility of Herpes Simplex Virus Isolated from Genital Herpes Lesions to ASP2151, a Novel Helicase-Primase Inhibitor

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00133-12 ◽

2012 ◽

Vol 56 (7) ◽

pp. 3587-3591 ◽

Cited By ~ 13

Author(s):

Kiyomitsu Katsumata ◽

Adriana Weinberg ◽

Koji Chono ◽

Shoji Takakura ◽

Toru Kontani ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Genital Herpes ◽

Antiviral Agents ◽

Term Treatment ◽

Recurrent Genital Herpes ◽

Short Term Treatment ◽

Varicella Zoster ◽

Simplex Virus ◽

Hsv 1

ABSTRACTASP2151 (amenamevir) is a helicase-primase inhibitor against herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus. To evaluate the anti-HSV activity of ASP2151, susceptibility testing was performed on viruses isolated from patients participating in a placebo- and valacyclovir-controlled proof-of-concept phase II study for recurrent genital herpes. A total of 156 HSV strains were isolated prior to the dosing of patients, and no preexisting variants with less susceptibility to ASP2151 or acyclovir (ACV) were detected. ASP2151 inhibited HSV-1 and HSV-2 replication with mean 50% effective concentrations (EC50s) of 0.043 and 0.069 μM, whereas ACV exhibited mean EC50s of 2.1 and 3.2 μM, respectively. Notably, the susceptibilities of HSV isolates to ASP2151 and ACV were not altered after dosing with the antiviral agents. Taken together, these results demonstrate that ASP2151 inhibits the replication of HSV clinical isolates more potently than ACV, and HSV resistant to this novel helicase-primase inhibitor as well as ACV may not easily emerge in short-term treatment for recurrent genital herpes patients.

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Contrasting Effects of W781V and W780V Mutations in Helix N of Herpes Simplex Virus 1 and Human Cytomegalovirus DNA Polymerases on Antiviral Drug Susceptibility

Journal of Virology ◽

10.1128/jvi.03360-14 ◽

2015 ◽

Vol 89 (8) ◽

pp. 4636-4644 ◽

Cited By ~ 8

Author(s):

Jocelyne Piret ◽

Nathalie Goyette ◽

Brian E. Eckenroth ◽

Emilien Drouot ◽

Matthias Götte ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Dna Polymerase ◽

Dna Polymerases ◽

Antiviral Drug ◽

Drug Susceptibility ◽

Herpes Simplex Virus 1 ◽

Simplex Virus ◽

Antiviral Drug Susceptibility ◽

Hsv 1

ABSTRACTDNA polymerases of theHerpesviridaeand bacteriophage RB69 belong to the α-like DNA polymerase family. In spite of similarities in structure and function, the RB69 enzyme is relatively resistant to foscarnet, requiring the mutation V478W in helix N to promote the closed conformation of the enzyme to make it susceptible to the antiviral. Here, we generated recombinant herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) mutants harboring the revertant in UL30 (W781V) and UL54 (W780V) DNA polymerases, respectively, to further investigate the impact of this tryptophan on antiviral drug susceptibility and viral replicative capacity. The mutation W781V in HSV-1 induced resistance to foscarnet, acyclovir, and ganciclovir (3-, 14-, and 3-fold increases in the 50% effective concentrations [EC50s], respectively). The recombinant HCMV mutant harboring the W780V mutation was slightly resistant to foscarnet (a 1.9-fold increase in the EC50) and susceptible to ganciclovir. Recombinant HSV-1 and HCMV mutants had altered viral replication kinetics. The apparent inhibition constant values of foscarnet against mutant UL30 and UL54 DNA polymerases were 45- and 4.9-fold higher, respectively, than those against their wild-type counterparts. Structural evaluation of the tryptophan position in the UL54 DNA polymerase suggests that the bulkier phenylalanine (fingers domain) and isoleucine (N-terminal domain) could induce a tendency toward the closed conformation greater than that for UL30 and explains the modest effect of the W780V mutation on foscarnet susceptibility. Our results further suggest a role of the tryptophan in helix N in conferring HCMV and especially HSV-1 susceptibility to foscarnet and the possible contribution of other residues localized at the interface between the fingers and N-terminal domains.IMPORTANCEDNA polymerases of theHerpesviridaeand bacteriophage RB69 belong to the α-like DNA polymerase family. However, the RB69 DNA polymerase is relatively resistant to the broad-spectrum antiviral agent foscarnet. The mutation V478W in helix N of the fingers domain caused the enzyme to adopt a closed conformation and to become susceptible to the antiviral. We generated recombinant herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) mutants harboring the revertant in UL30 (W781V) and UL54 (W780V) DNA polymerases, respectively, to further investigate the impact of this tryptophan on antiviral drug susceptibility. The W781V mutation in HSV-1 induced resistance to foscarnet, whereas the W780V mutation in HCMV slightly decreased drug susceptibility. This study suggests that the different profiles of susceptibility to foscarnet of the HSV-1 and HCMV mutants could be related to subtle conformational changes resulting from the interaction between residues specific to each enzyme that are located at the interface between the fingers and the N-terminal domains.

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Use of a Single Monoclonal Antibody To Determine the Susceptibilities of Herpes Simplex Virus Type 1 and Type 2 Clinical Isolates to Acyclovir

Clinical and Vaccine Immunology ◽

10.1128/cdli.9.6.1379-1381.2002 ◽

2002 ◽

Vol 9 (6) ◽

pp. 1379-1381 ◽

Cited By ~ 2

Author(s):

Christine Chutkowski ◽

Betty Olson ◽

Ann McDonough ◽

James Mahoney ◽

James J. McSharry

Keyword(s):

Monoclonal Antibody ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Drug Susceptibility ◽

Clinical Isolates ◽

Drug Concentrations ◽

Effective Doses ◽

Simplex Virus

ABSTRACT This report describes a flow cytometry drug susceptibility assay that uses a single fluorochrome-labeled monoclonal antibody to determine the acyclovir susceptibilities of herpes simplex virus (HSV) type 1 or type 2 clinical isolates. This assay yields 50% effective doses (drug concentrations that reduce the number of antigen-positive cells by 50%) for HSV clinical isolates that are equivalent to those obtained with the plaque reduction assay.

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Theaflavin-3,3′-Digallate and Lactic Acid Combinations Reduce Herpes Simplex Virus Infectivity

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00659-13 ◽

2013 ◽

Vol 57 (8) ◽

pp. 3806-3814 ◽

Cited By ~ 14

Author(s):

Charles E. Isaacs ◽

Weimin Xu

Keyword(s):

Lactic Acid ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Antiviral Activity ◽

Female Reproductive Tract ◽

Clinical Isolates ◽

Virus Infectivity ◽

Ph Range ◽

Simplex Virus ◽

Hsv 1

ABSTRACTThe present study examined the efficacy of using multiple mechanisms as part of a topical microbicide to inactivate herpes simplex virus (HSV) by combining theaflavin-3,3′-digallate (TF-3) and lactic acid (LA) over the pH range of 4.0 to 5.7 to mimic conditions in the female reproductive tract. Six clinical isolates of HSV-2 and two clinical isolates of HSV-1 were almost completely inactivated when TF-3 (100 μM) was present with LA over the pH range of 4.5 to 5.7, whereas four additional HSV-1 clinical isolates required TF-3 concentrations of 250 to 500 μM for comparable virus titer reduction. LA (1%) alone at pH 4.0 reduced the titers of laboratory and clinical isolates of HSV-1 and HSV-2 by ≥5 log10, but most LA-dependent antiviral activity was lost at a pH of ≥4.5. When HSV-1 and HSV-2 were incubated at pH 4.0 without LA virus titers were not reduced. At pH 4.0, HSV-1 and HSV-2 titers were reduced 5 log10in 20 min by LA alone. TF-3 reduced HSV-2 titers by 5 log10in 20 to 30 min at pH 4.5, whereas HSV-1 required 60 min for comparable inactivation. Mixtures of TF-3 and LA stored at 37°C for 1 month at pH 4.0 to 5.7 maintained antiviral activity. Semen, but not cervical vaginal fluid, decreased LA-dependent antiviral activity at pH 4.0, but adding TF-3 to the mixture reduced HSV titers by 4 to 5 log10. These results indicate that a combination microbicide containing TF-3 and LA could reduce HSV transmission.

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Prevalence of pathogenic Klebsiella pneumoniae based on PCR capsular typing harbouring carbapenemases encoding genes in Uganda tertiary hospitals

Antimicrobial Resistance and Infection Control ◽

10.1186/s13756-021-00923-w ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Kenneth Ssekatawa ◽

Denis K. Byarugaba ◽

Jesca L. Nakavuma ◽

Charles D. Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Virulence Factors ◽

Carbapenem Resistance ◽

Clinical Isolates ◽

Genotypic Resistance ◽

Pathogenic Potential ◽

Phenotypic Resistance ◽

Tertiary Hospitals ◽

Encoding Genes

Abstract Background Klebsiella pneumoniae is an opportunistic pathogen that has been implicated as one of commonest cause of hospital and community acquired infections. The K. pneumoniae infections have considerably contributed to morbidity and mortality in patients with protracted ailments. The capacity of K. pneumoniae to cause diseases depends on the presence of an array virulence factors. Coexistence and expression of virulence factors and genetic determinants of antibiotic resistance complicates treatment outcomes. Thus, emergence of pathogenic MDR K. pneumoniae poses a great threat to the healthcare system. However, the carriage of antibiotic resistance among pathogenic K. pneumoniae is yet to be investigated in Uganda. We sought to investigate the carbapenem resistance profiles and pathogenic potential based on capsular serotypes of K. pneumoniae clinical isolates. Methods This was a cross sectional study involving use of archived Klebsiella pneumoniae isolates collected between January and December, 2019 at four tertiary hospitals in Uganda. All isolates were subject to antimicrobial susceptibility assays to determine phenotypic antibiotic resistance, pentaplex PCR to detect carbapenemases encoding genes and heptaplex PCR to identify capsular serotypes K1, K2, K3, K5, K20, K54 and K57. Results The study found an overall phenotypic carbapenem resistance of 23.3% (53/227) and significantly higher genotypic resistance prevalence of 43.1% (98/227). Over all, the most prevalent gene was blaOXA-48-like (36.4%), followed by blaIMP-type (19.4%), blaVIM-type (17.1%), blaKPC-type (14.0%) and blaNDM-type (13.2%). blaVIM-type and blaOXA-48-like conferred phenotypic resistance in all isolates and 38.3% of isolates that harbored them respectively. Capsular multiplex PCR revealed that 46.7% (106/227) isolates were pathogenic and the predominantly prevalent pathotype was K5 (18.5%) followed by K20 (15.1%), K3 (7.1%), K2 (3.1%) and K1 (2.2%). Of the 106 capsular serotypes, 37 expressed phenotypic resistance; thus, 37 of the 53 carbapenem resistant K. pneumoniae were pathogenic. Conclusion The high prevalence of virulent and antibiotic resistant K. pneumoniae among clinical isolates obtained from the four tertiary hospital as revealed by this study pose a great threat to healthcare. Our findings underline the epidemiological and public health risks and implications of this pathogen.

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Prevalence of Pathogenic Klebsiella Pneumoniae based on PCR Capsular Typing Harbouring Carbapenemases Encoding Genes in Ugandan Tertiary Hospitals

10.21203/rs.3.rs-97785/v1 ◽

2020 ◽

Author(s):

Kenneth Ssekatawa ◽

Denis K. Byarugaba ◽

Jesca L. Nakavuma ◽

Charles D. Kato ◽

Francis Ejobi ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Carbapenem Resistance ◽

Clinical Isolates ◽

Genotypic Resistance ◽

Cross Sectional ◽

Pathogenic Potential ◽

Phenotypic Resistance ◽

Tertiary Hospitals ◽

Encoding Genes

Abstract Background: Klebsiella pneumoniae is an opportunistic pathogen that has been implicated as one of commonest cause of hospital and community acquired infections. The K. pneumoniae infections have considerably contributed to morbidity and mortality in patients with protracted ailments. The capacity of K. pneumonia to cause diseases depends on presence of an array virulent factors. Coexistence and expression of virulent factors and genetic determinants of antibiotic resistance complicates treatment outcomes. Thus, emergence of pathogenic MDR K. pneumoniae poses a great threat to the healthcare system. However, the carriage of antibiotic resistance among pathogenic K. pneumoniae is yet to be investigated in Uganda. We sought to investigate the carbapenem resistance profiles and pathogenic potential based on capsular serotypes of K. pneumoniae clinical isolates. Methods: This was a cross sectional study involving use of archived Klebsiella pneumoniae isolates collected between January and December, 2019 at four tertiary hospitals in Uganda. All isolates were subject to antimicrobial susceptibility assays to determine phenotypic antibiotic resistance, pentaplex PCR to detect carbapenemases encoding genes and heptaplex PCR to identify capsular serotypes K1, K2, K3, K5, K20, K54 and K57.Results: The study found an overall phenotypic carbapenem resistance of 23.3% (53/227) and significantly higher genotypic resistance prevalence of 43.1% (98/227). Over all, the most prevalent gene was blaOXA-48-like (36.4%), followed by blaIMP-type (19.4%), blaVIM-type (17.1), blaKP-type (14.0%) and blaNDM-type (13.2%). blaVIM-type and blaOXA-48-like conferred phenotypic resistance in all isolates and 38.3% isolates that harbored them respectively. Capsular multiplex PCR revealed that 46.7% (106/227) isolates were pathogenic and the predominantly prevalent pathotype was K5 (18.5%) followed by K20 (14.1%), K3 (7.1%), K2 (3.1%) and K1 (2.2%). Of the 106 capsular serotypes, 37 expressed phenotypic resistance; thus, 37 of the 53 carbapenem resistant K. pneumoniae were pathogenic.Conclusion: The high prevalence of virulent and antibiotic resistant K. pneumoniae among clinical isolates obtained from the four tertiary hospital as revealed by this study pose a great threat to healthcare. Our findings underline the epidemiological and public health risks and implications of this pathogen.

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Application of Real-Time PCR for Determination of Antiviral Drug Susceptibility of Herpes Simplex Virus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.9.2943-2947.2002 ◽

2002 ◽

Vol 46 (9) ◽

pp. 2943-2947 ◽

Cited By ~ 22

Author(s):

Růžena Stránská ◽

Anton M. van Loon ◽

Merjo Polman ◽

Rob Schuurman

Keyword(s):

Herpes Simplex ◽

Real Time ◽

Real Time Pcr ◽

Antiviral Drug ◽

Drug Susceptibility ◽

Pcr Assay ◽

Simplex Virus ◽

Antiviral Drug Susceptibility ◽

Hsv 1

ABSTRACT A quantitative real-time PCR (TaqMan) assay was developed for determination of antiviral drug susceptibility of herpes simplex virus (HSV). After short-time culture of the virus, the antiviral drug susceptibility of HSV isolates for acyclovir (ACV) was determined by measuring the reduction of the HSV type 1 (HSV-1) DNA levels in culture supernatants using real-time PCR. The 50% inhibitory concentration was reported as the concentration of antiviral drug that reduced the number of HSV-1 DNA copies by 50%. A total of 15 well-characterized ACV-sensitive or -resistant strains and clinical isolates were used for assay evaluation. The new assay with real-time PCR readout permitted rapid (3 days), objective, and reproducible determination of HSV-1 drug susceptibilities with no need for stringent control of initial multiplicity of infection. Furthermore, the real-time PCR assay results showed good correlation (r = 0.86) with those for the plaque reduction assay. In conclusion, the real-time PCR assay described here is a suitable quantitative method for determination of antiviral susceptibility of HSV-1, amenable for use in the routine diagnostic virology laboratory.

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Epigallocatechin Gallate Inactivates Clinical Isolates of Herpes Simplex Virus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00825-07 ◽

2008 ◽

Vol 52 (3) ◽

pp. 962-970 ◽

Cited By ~ 78

Author(s):

Charles E. Isaacs ◽

Guang Y. Wen ◽

Weimin Xu ◽

Jun Hua Jia ◽

Lisa Rohan ◽

...

Keyword(s):

Molecular Weight ◽

Herpes Simplex Virus ◽

Herpes Simplex ◽

Green Tea ◽

Sodium Dodecyl ◽

Epigallocatechin Gallate ◽

Clinical Isolates ◽

Envelope Glycoproteins ◽

Simplex Virus ◽

Hsv 1

ABSTRACT In the absence of a fully effective herpes simplex virus (HSV) vaccine, topical microbicides represent an important strategy for preventing HSV transmission. (−)-Epigallocatechin gallate (EGCG) (molecular weight, 458.4) is the primary catechin in green tea. The present study shows that EGCG has greater anti-HSV activity than other green tea catechins and inactivates multiple clinical isolates of HSV type 1 (HSV-1) and HSV-2. EGCG reduced HSV-2 titers by ≥1,000-fold in 10 to 20 min and reduced HSV-1 titers by the same amount in 30 to 40 min. The anti-HSV activity of EGCG is due to a direct effect on the virion, and incubating Vero and CV1 cells with EGCG for 48 h prior to infection with HSV-1 and HSV-2, respectively, does not reduce HSV production. Electron microscopic (EM) studies showed that purified virions exposed to EGCG were damaged, and EM immunogold labeling of the envelope glycoproteins gB and gD was significantly reduced following EGCG treatment while capsid protein labeling was unchanged. When purified HSV-1 envelope glycoproteins gB and gD were incubated with EGCG and then examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lower-molecular-weight gB and gD bands decreased and new higher-molecular-weight bands appeared, indicating the EGCG-dependent production of macromolecular complexes. gB and gD are essential for HSV infectivity, and these results suggest that EGCG could inactivate HSV virions by binding to gB, gD, or another envelope glycoprotein. EGCG is stable in the pH range found in the vagina and appears to be a promising candidate for use in a microbicide to reduce HSV transmission.

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