ABSTRACT
In recent years, with increased the prevalence of viral infections and having no specific for their treatment and also the continuous appearance of resistant viral strains, the finding of novel antiviral agents is necessary. In this study, monoterpenes of thymol, carvacrol, p-cymene and essential oils from Sinapis arvensis L., Lallemantia royleana Benth. and Pulicaria vulgaris Gaertn. were screened for their inhibitory effect against herpes simplex virus type 1 (HSV-1) in vitro on Vero cell line CCL-81-ATCC using a plaque reduction assay. The antiviral activity of three monoterpenes (thymol, carvacrol and p-cymene) and three essential oils were evaluated by cytotoxicity assay, direct plaque test. In addition, the modes of antiviral action of these compounds were investigated during the viral infection cycle. Results showed that the inhibitory concentrations (IC50) were determined at 0.002%, 0.037%, >0.1%, 0.035%, 0.018% and 0.001% for thymol, carvacrol, p-cymene, S. arvensis oil, L. royleana oil and P. vulgaris oil, respectively. A manifestly dose-dependent virucidal activity against HSV-1 could be exhibited for compounds tested. In order to determine the mode of the inhibitory effect, compounds were added at different stages during the viral infection cycle. At maximum noncytotoxic concentrations of the compounds, plaque formation was significantly reduced by more than 80% when HSV-1 was preincubated with p-cymene. However, no inhibitory effect could be observed when the compounds were added to the cells prior to infection with HSV-1 or after the adsorption period. CONCLUSION: These results indicate that compounds affected HSV-1 mostly before adsorption and might interact with the viral envelope. Thymol exhibited a high selectivity index and seems to be a promising candidate for topical therapeutic application as antiviral agent for treatment of herpetic infections.
Subject(s)
Antiviral Agents/pharmacology , Herpesvirus 1, Human/drug effects , Monoterpenes/pharmacology , Oils, Volatile/pharmacology , Thymol/pharmacology , Animals , Antiviral Agents/isolation & purification , Chlorocebus aethiops , Cymenes , Herpesvirus 1, Human/growth & development , Lamiaceae/chemistry , Microbial Sensitivity Tests , Monoterpenes/isolation & purification , Oils, Volatile/isolation & purification , Pulicaria/chemistry , Sinapis/chemistry , Thymol/isolation & purification , Vero Cells , Viral Plaque AssayABSTRACT
In order to investigate the hypothesis that the mammalian target of rapamycin inhibitor everolimus (EVR) shows anticytomegalovirus (CMV) activity in pediatric patients, we analyzed the impact of EVR-based immunosuppressive therapy on CMV replication and disease in a large cohort (n = 301) of pediatric kidney allograft recipients. The EVR cohort (n = 59), who also received low-dose cyclosporin, was compared with a control cohort (n = 242), who was administered standard-dose cyclosporin or tacrolimus and an antimetabolite, mostly mycophenolate mofetil (91.7%). Multivariate analysis revealed an 83% lower risk of CMV replication in the EVR cohort than in the control cohort (p = 0.005). In CMV high-risk (donor+/recipient-) patients (n = 88), the EVR-based regimen was associated with a significantly lower rate of CMV disease (0% vs. 14.3%, p = 0.046) than the standard regimen. In patients who had received chemoprophylaxis with (val-)ganciclovir (n = 63), the CMV-free survival rates at 1 year and 3 years posttransplant (100%) were significantly (p = 0.015) higher in the EVR cohort (n = 15) than in the control cohort (n = 48; 1 year, 75.0%; 3 years, 63.3%). Our data suggest that in pediatric patients at high risk of CMV, an EVR-based immunosuppressive regimen is associated with a lower risk of CMV disease than a standard-dose calcineurin inhibitor-based regimen.
Subject(s)
Cyclosporine/administration & dosage , Cytomegalovirus Infections/prevention & control , Everolimus/therapeutic use , Graft Rejection/prevention & control , Kidney Transplantation , Postoperative Complications , Virus Replication/drug effects , Child , Cytomegalovirus/drug effects , Cytomegalovirus Infections/virology , Female , Follow-Up Studies , Glomerular Filtration Rate , Graft Rejection/virology , Graft Survival/drug effects , Humans , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/surgery , Kidney Function Tests , Male , Prognosis , Retrospective Studies , Risk Factors , Survival RateABSTRACT
BACKGROUND: In the past, anaesthetic breathing circuits were identified as a source of pathogen transmission. It is still debated, whether breathing circuits combined with breathing system filters can be safely used for more than 1 day. The aim of this study was to evaluate the transmission risk of bacteria and also viruses via breathing circuits after extended use. METHODS: The inner and outer surface of 102 breathing circuits used for 1 day and of 101 circuits used for 7 days were examined for bacteria and viruses. Additionally, 10 and 20 breathing circuits each were examined after use on patients with pulmonary virus infection and with multidrug-resistant organism (MDRO) colonisation/infection respectively. Bacteria were detected by standard microbiological procedures; PCR techniques were applied for herpes simplex virus, cytomegalovirus, influenza, parainfluenza and respiratory syncytial virus. RESULTS: Endoluminal bacterial contamination of breathing circuits remained unchanged after 7-day vs. 1-day use (5.9% vs. 7.8%) [CI95%: -0.0886-0.0506, pnon-inferiority 0.0260]. Only outside surface contamination with bacteria belonging to environmental species or human flora increased (16.8 vs. 6.9%) [CI 95%: 0.0118 - 0.1876, pnon-inferiority 0.8660]. Viruses occurred on the patient side, but not in breathing circuits. No MDRO occurred in the 20 circuits after use on patients harbouring such germs. CONCLUSION: Endoluminal contamination of breathing circuits with bacteria did not increase after extended use. No viruses were detected in the breathing circuits using filters. Based on our results, the extended use of ABC without exceptions appears safe, if a high level of anaesthesia workplace cleaning is secured.
Subject(s)
Anesthesiology/instrumentation , Bacteria/isolation & purification , Equipment Contamination , Patient Safety , Respiration, Artificial/instrumentation , Viruses/isolation & purification , Equipment Reuse , HumansABSTRACT
Piroxicam is a potent, nonsteroidal, anti-inflammatory agent (NSAID) which also exhibits antipyretic activity. The antiviral effect of piroxicam against herpes simplex virus type 1 (HSV-1) was examined in vitro on RC-37 monkey kidney cells using a plaque reduction assay. Piroxicam was dissolved in ethanol or dimethylsulfoxide (DMSO) and the 50% inhibitory concentration (IC50) was determined at 4 µg/ml and 75 µg/ml, respectively. The IC50 for the standard antiherpetic drug acyclovir was determined at 1.6 µM. At non-cytotoxic concentrations of these piroxicam solutions, plaque formation was significantly reduced by 62.4% for ethanolic piroxicam and 72.8% for piroxicam in DMSO. The mode of antiviral action of these drugs was assessed by time-on-addition assays. No antiviral effect was observed when cells were incubated with piroxicam prior to infection with HSV-1 or when HSV-1 infected cells were treated with dissolved piroxicam. Herpesvirus infection was, however, significantly inhibited when HSV-1 was incubated with piroxicam prior to the infection of cells. These results indicate that piroxicam affected the virus before adsorption, but not after penetration into the host cell, suggesting that piroxicam exerts a direct antiviral effect on HSV-1. Free herpesvirus was sensitive to piroxicam in a concentration-dependent manner and the inhibition of HSV-1 appears to occur before entering the cell but not after penetration of the virus into the cell. Considering the lipophilic nature of piroxicam, which enables it to penetrate the skin, it might be suitable for topical treatment of herpetic infections.
Subject(s)
Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Herpes Simplex/prevention & control , Herpesvirus 1, Human/drug effects , Piroxicam/pharmacology , Piroxicam/therapeutic use , Acyclovir/pharmacology , Animals , Cell Line , Cell Survival/drug effects , Chlorocebus aethiops , Viral Plaque AssayABSTRACT
Essential oils of medicinal plants are increasingly of interest as novel drugs for antiherpetic agents, since herpes simplex virus (HSV) might develop resistance to commonly used antiviral drugs. The antiviral effect of Olbas, a traditionally used complex essential oil, and of cajuput oil, a major constitutent of Olbas, against HSV type 1 was examined. The antiviral activity of these essential oils was tested in vitro on monkey kidney cells using a plaque reduction assay. The 50% inhibitory concentration (IC50) of Olbas and cajuput oil for herpes simplex virus plaque formation was determined at 1.8 microg/ml and 7.5 microg/ml, respectively. At noncytotoxic concentrations of these oils, plaque formation was significantly reduced by 99% for Olbas and 66% for cajuput oil. The selectivity index of 150 for Olbas against herpes simplex virus was superior to a rather low selectivity index for cajuput oil. The mode of antiviral action of these essential oils was assessed by time-on-addition assays. Herpesvirus was significantly inhibited by pretreatment with Olbas essential oil prior to infection of cells. These results indicate that Olbas affected the virus before adsorption, but not after penetration into the host cell, thus Olbas exerted a direct antiviral effect on HSV. A clearly time-dependent antiviral activity for Olbas and cajuput oil could be demonstrated. Considering the lipophilic nature of the Olbas complex essential oil mixture, which enables it to penetrate the skin, and a high selectivity index, Olbas might be suitable for topical treatment of herpetic infections.
Subject(s)
Antiviral Agents , Herpesvirus 1, Human/drug effects , Oils, Volatile/pharmacology , Animals , Cell Line , Cell Survival/drug effects , Chlorocebus aethiops , Inhibitory Concentration 50 , Viral Plaque Assay , Virus Attachment/drug effects , Virus Replication/drug effectsABSTRACT
The need to discover and develop alternative therapies to treat multidrug-resistant bacterial infections is timely. The aim of this study was to examine the antimicrobial potential of propolis, as a purified and concentrated special extract GH 2002, against clinical isolates of Streptococcus pyogenes, methicillin-resistent Stapylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE) and Candida. Minimal inhibitory concentrations (MICs) and minimal microbicidial concentrations (MMCs) of propolis against microbial pathogens were evaluated using the broth microdilution method. Propolis extract GH 2002 revealed low MICs in the range of 0.03 to 2 mg/ml against S. pyogenes, S. aureus, E. faecium and Candida. A high bactericidal activity of propolis extract in the range of 0.06 to 1.0 mg/ml was determined for S. pyogenes and S. aureus, however propolis was not bactericidal against E. faecium. Propolis concentrations between 0.6 and 2.4 mg/ml displayed fungicidal activity against different Candida species. Whereas all tested MRSA strains were highly susceptible against propolis, only minor activity was found against VRE strains. Time-kill curves demonstrated a high antimicrobial activity at low MICs already after few hours of incubation against reference strains, clinical antibiotic-susceptible strains, clinical antifungal susceptible strains as well as all tested clinical MRSA strains, but not against VRE strains. In conclusion, clinical drug-sensitive as well as some clinical multidrug-resistant microbial isolates, i.e. MRSA, were susceptible to propolis with different degrees of susceptibility. These results suggest that the special propolis extract GH2002 might be used in the development of alternative products for therapy of microbial infections.
Subject(s)
Anti-Infective Agents , Drug Resistance, Fungal/drug effects , Drug Resistance, Multiple, Bacterial/drug effects , Propolis/pharmacology , Candida/drug effects , Enterococcus faecium/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Streptococcus pyogenes/drug effects , Vancomycin ResistanceABSTRACT
Natural substances offer interesting pharmacological perspectives for antiviral drug development with regard to broad spectrum antiviral properties and novel modes of action. Drugs currently used to treat cutaneous or genital herpetic infections are effective in limiting disease, but the emergence of drug-resistant viruses in immunocompromised individuals can be problematic. A nontoxic cyanobacterium Arthrospira strain from Chad has been characterized by sequence analysis of the intergenic spacer region of the phycocyanin gene. This cyanobacterium was identified as Arthrospira fusiformis by phylogenetic tree analysis. The antiherpetic activity of crude aqueous extracts from the Chad A. fusiformis isolate was determined. Antiviral efficacy against herpes simplex virus of cold water extract, hot water extract and phosphate buffer extract was assessed in plaque reduction assays and their mode of antiherpetic action was analysed. In virus suspension assays, cold water extract, hot water extract and phosphate buffer extract inhibited virus infectivity by 54.9%, 64.6%, and 99.8%, respectively, in a dose-dependent manner. The mode of antiviral action was determined by addition of cyanobacterial extracts separately at different time periods during the viral infection cycle. Extracts of A. fusiformis strain clearly inhibited herpesvirus multiplication before and during virus infection of host cells. The phosphate buffer extract of the A. fusiformis strain affected free herpes simplex virus prior to infection of host cells and inhibited intracellular viral replication. It is concluded, that Arthrospira compounds warrant further investigation to examine their potential role in the treatment of herpetic infections.
Subject(s)
Antiviral Agents/pharmacology , Cyanobacteria/chemistry , Simplexvirus/drug effects , Animals , Cell Line , Cell Survival/drug effects , Chad , Chlorocebus aethiops , Culture Media , Cyanobacteria/growth & development , Phycocyanin/chemistry , Phylogeny , Viral Plaque AssayABSTRACT
BACKGROUND: Respiratory syncytial virus (RSV) is the leading cause of hopitalisation in young children with respiratory tract infections (RTI). The aim of this research project was to analyse RSV genotypes and the diversification of RSV strains among hospitalised children in Heidelberg, Germany. METHODS: We prospectively analysed nasopharyngeal swabs (NPS) from children who were hospitalised with acute RTI at the University Hospital Heidelberg, Germany, during winter seasons 2014 to 2017. RSV RT-PCR and RSV sequence analysis of the G gene coding for the attachment glycoprotein were performed. Clinical data was obtained using a standardised questionnaire. RESULTS: RSV was detected in 405 out of 946 samples from hospitalised children. Most RSV positive children were below the age of two years (84.4%) and had a lower RTI (78.8%). The majority of RSV positive children was male, significantly younger than RSV negative children with a median age of 0.39 years and with more severe respiratory symptoms. Out of 405 positive samples, 317 RSV strains were successfully sub-grouped into RSV subtypes A (57.4%; 182/317) and B (42.6%; 135/317). Both RSV subtypes cocirculated in all analysed winter seasons. Phylogenetic analysis of 317 isolates revealed that the majority of RSV-A strains (180/182) belonged to the ON1 genotype, most RSV-B strains could be attributed to the BAIX genotype (132/135). ON1 and BAIX strains showed a sub-differentiation into different lineages and we were able to identify new (sub)genotypes. CONCLUSION: Analysis of the molecular epidemiology of RSV from different seasons revealed the cocirculation and diversification of RSV genotypes ON1 and BAIX.
Subject(s)
Child, Hospitalized/statistics & numerical data , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus, Human/genetics , Adolescent , Child , Child, Preschool , Female , Germany/epidemiology , Humans , Infant , Infant, Newborn , Male , Molecular Epidemiology , Phylogeny , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/classificationABSTRACT
Resistance to linezolid has been associated with a G2576T mutation in the 23 S rRNA gene. Clinical isolates of linezolid-sensitive and linezolid-resistant vancomycin-resistant Enterococcus faecium of a liver transplant patient have been analysed for the G2576T mutation by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), conventional sequencing and pyrosequencing. A clear association between the number of mutated 23 S rRNA genes and the level of linezolid resistance has been demonstrated. Linezolid susceptibility re-emerged after cessation of linezolid therapy; however, the re-initiation of linezolid therapy resulted in the re-emergence of linezolid-resistant strains. Pyrosequencing rapidly detected the number of mutated alleles and is superior to conventional PCR-RFLP for the detection of heterozygous mutations.
Subject(s)
Acetamides/pharmacology , Anti-Bacterial Agents/pharmacology , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Drug Resistance, Bacterial , Enterococcus faecium/drug effects , Oxazolidinones/pharmacology , Point Mutation , DNA, Bacterial/chemistry , DNA, Ribosomal/chemistry , Enterococcus faecium/genetics , Humans , Linezolid , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 23S/genetics , Sequence Analysis, DNAABSTRACT
Essential oils from various aromatic medicinal plants are highly active against some viral infections, e.g. labial herpes caused by herpes simplex virus type 1. Balm oil, tea tree oil and peppermint oil demonstrate in vitro a significant antiherpetic activity, mainly related to a direct drug-virus particle interaction, some essential oils also act directly virucidal. Interestingly, these essential oils are also highly active against acyclovir-resistant herpes simplex virus strains. In clinical studies, tea tree oil has been shown to possess antiherpetic, anti-inflammatory and pain-relieving properties, as well as to accelerate the healing process of herpes labialis. Applying diluted essential oils three to four times daily for the antiherpetic treatment of affected areas is recommended. Some companies have marketed plant products, e.g. from Melissa, for the treatment of recurrent herpetic infections.
Subject(s)
Herpesviridae Infections/drug therapy , Phytotherapy/methods , Plant Extracts/therapeutic use , Plants, Medicinal/chemistry , HumansABSTRACT
In recent years there has been an increasing interest for application of natural products as antiinfectives and concerns about the safety of synthetic compounds have encouraged more detailed studies of natural resources. Two different strains of the nontoxic cyanobacterium Arthrospira from the United States and Egypt have been characterized by sequence analysis of the intergenic spacer region of the phycocyanin gene. Both cyanobacteria were identified as Arthrospira fusiformis by phylogenetic tree analysis. The antiherpetic activity of crude aqueous extracts from the US and the Egyptian A. fusiformis isolates was determined. Antiviral activity against herpes simplex virus of cold water extracts, hot water extracts and phosphate buffer extracts from the American and the Egyptian strains was assessed in plaque reduction assays and their mode of antiherpetic action was analysed. In virus suspension assays, all extracts of the American cyanobacterium and the phosphate buffer extract of the Egyptian cyanobacterium inhibited virus infectivity by > 90% in a dose-dependent manner. Phosphate buffer extract and hot water extract of the US cyanobacterium demonstrated the highest antiviral activity at low extract concentrations with high selectivity indices of 7464 and 542, respectively. The mode of antiviral action has been determined by addition of cyanobacterial extracts separately at different time periods during the viral infection cycle. Two extracts of the US A. fusiformis strain clearly inhibited herpesvirus multiplication before and after virus infection of host cells. In contrast, extracts of the Egyptian A. fusiformis strain affected only free herpes simplex virus prior to infection of host cells by direct inactivation of virus particles. In this study different Arthrospira crude extracts showed a significant antiviral effect and might be applied in recurrent herpetic infections.
Subject(s)
Antiviral Agents/pharmacology , Cyanobacteria/chemistry , Simplexvirus/drug effects , Acyclovir/pharmacology , Antiviral Agents/chemistry , Cell Line , Dose-Response Relationship, Drug , Egypt , Humans , Phosphates/chemistry , United States , Viral Plaque Assay , WaterABSTRACT
Varicella zoster virus (VZV) seronegative patients under immunosuppressive therapy are at risk for severe life-threatening varicella. A 25-year-old male patient presented with rash and hepatitis. He had been known to suffer from Crohn's disease and received immunosuppressive treatment with azathioprine. The patient showed dyspnoea, and presented with a generalized rash with vesicular lesions typical for herpesvirus infections. He was started immediately on acyclovir therapy. Varicella infection was determined in this VZV seronegative patient in rash vesicles, blood and tracheal secretions and a high VZV viral load was detected in these specimens. The causative agent was genotyped by sequencing of several genes as a variant of the European genotype E2 containing several unique single nucleotide polymorphisms. Despite all measures, there was progressive septic shock, and the patient died due to multi-organ failure. Immunocompromised adults without varicella history are at high risk to develop life-threatening complications of varicella. Antiviral therapy with acyclovir can only be successful when administered as early as possible on suspicion of varicella infection in this group of patients. The most effective method to prevent severe varicella in immunocompromised patients is active immunization prior to immunosuppressive therapy.
Subject(s)
Chickenpox/virology , Herpesvirus 3, Human/classification , Herpesvirus 3, Human/genetics , Adult , Azathioprine/adverse effects , Azathioprine/therapeutic use , Blood/virology , Chickenpox/pathology , Chickenpox/physiopathology , Crohn Disease/complications , Crohn Disease/drug therapy , DNA, Viral/genetics , Fatal Outcome , Genotype , Herpesvirus 3, Human/isolation & purification , Humans , Immunocompromised Host , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Male , Multiple Organ Failure , Sequence Analysis, DNA , Shock, Septic , Trachea/virologyABSTRACT
We report on the antiviral potency of an aqueous extract of root/stem bark of Rhus aromatica (fragrant sumac extract) against herpes simplex virus type 1 and type 2 in cell culture (RC-37 cells) using a plaque reduction assay. The extract exhibited a high level of anti-HSV activity with IC50-values of 0.0005% for HSV-1 and 0.0043% for HSV-2 as well as high selectivity indices (SI) of 5400 for HSV-1 and 628 for HSV-2. In order to determine the mode of antiviral action, the fragrant sumac extract was added at different times to the cells or viruses during the viral infection cycle. At maximum non-cytotoxic concentration (0.25%), plaque formation was significantly reduced by more than 99% when herpes simplex viruses were pretreated with the plant extract for 1 h prior to cell infection. When the host cells were pretreated with the fragrant sumac extract for 1 h prior to virus infection, the infectivity of viruses was reduced by 50% for HSV-1 but only moderately for HSV-2. No antiviral effect was seen when the plant extract was added to already infected host cells. Based on these findings the plant extract seems to interact not only with the viral envelope but also with the surface of the host cells impairing the ability of herpes simplex viruses to adsorb to and penetrate into the host cells. In conclusion, the aqueous fragrant sumac extract revealed a strong antiviral activity against HSV-1 and HSV-2 in vitro.
Subject(s)
Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Rhus/chemistry , Simplexvirus/drug effects , Acyclovir/pharmacology , Cell Survival/drug effects , Cells, Cultured , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Herpesvirus 1, Human/drug effects , Herpesvirus 2, Human/drug effects , Humans , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Roots/chemistry , Plant Stems/chemistry , Viral Plaque AssayABSTRACT
Medicinally and commercially important essential oils from the family Myrtaceae, i.e. cajuput, clove, kanuka and manuka were phytochemically analysed by GC-MS. Cytotoxicity of these essential oils was evaluated in a standard neutral red assay. Maximum noncytotoxic concentrations for cajuput oil and clove oil were determined at 0.006%, kanuka oil and manuka oil were more cytotoxic with a maximum noncytotoxic concentration of 0.001%. The compounds alpha-pinene, eugenol and leptospermone demonstrated maximum noncytotoxic concentrations at dilutions of 0.001%, 0.003% and 0.001%, respectively. However, the terpene 1,8-cineole was about 100 times less toxic to cultured cells with a maximum noncytotoxic concentration of 0.1% and a TC50 value of 0.44%. Manuka essential oil exhibited high levels of virucidal activity against HSV-1 as well against drug-resistant HSV-1 isolates in viral suspension tests. Determination of cytotoxicity of natural products is an important prerequisite for application in cosmetic and health care products and in antiviral tests.
Subject(s)
Antineoplastic Agents, Phytogenic , Myrtaceae/chemistry , Oils, Volatile/pharmacology , Animals , Antiviral Agents/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Chlorocebus aethiops , Chromatography, Gas , Herpesvirus 1, Human/drug effects , Humans , Oils, Volatile/chemistry , Vero Cells , Viral Plaque AssayABSTRACT
BACKGROUND: Respiratory syncytial virus (RSV) can be associated with severe disease and prolonged shedding in immunocompromised patients. OBJECTIVE: To investigate the genetic variability of RSV in consecutive samples of haematological patients with prolonged RSV shedding. STUDY DESIGN: Haematological patients at the University Hospital Heidelberg are routinely screened for respiratory viruses during winter season. In patients with prolonged RSV shedding between 2011 and 2014, Sanger-sequencing of the second hypervariable region of the RSV G gene was performed in consecutive samples. Further, deep-sequencing was performed in representative samples. RESULTS: Patients with prolonged RSV-A shedding were analysed (n=16, mean shedding 90days, 81.2% male). Phylogenetic analysis identified RSV genotypes NA1 (2011/12) or ON1 (2012/13). In most patients (n=12/16), Sanger-sequencing of the G gene showed identical sequences over the course of the shedding period. However, in two patients with particularly long viral shedding (333 and 142days), Sanger-sequencing revealed the presence of mutations leading to premature stop codons (37 and 70 amino acids truncated) in the G gene. In one additional patient, deep-sequencing revealed variants with premature stop codons at different positions. All three patients received repeatedly intravenous immunoglobulins. Interestingly, deep-sequencing revealed also a loss of the characteristic 72-nucleotide-duplication in all analysed ON1 strains. CONCLUSIONS: Long shedding periods and lack of immune selective pressure in the immunocompromised host seems to allow the persistence of viruses stripping a part of the C-terminus of the G glycoprotein. The loss of the characteristic 72-nucleotide-duplication in RSV-A ON1 variant strains is here described for the first time.
Subject(s)
Codon, Nonsense , Genotype , Hematologic Diseases/complications , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/isolation & purification , Sequence Deletion , Virus Shedding , Adult , Aged , Aged, 80 and over , Female , Germany , High-Throughput Nucleotide Sequencing , Humans , Immunocompromised Host , Male , Middle Aged , RNA, Viral/genetics , Respiratory Syncytial Virus, Human/classification , Respiratory Syncytial Virus, Human/genetics , Retrospective Studies , Sequence Analysis, DNAABSTRACT
During molecular cloning of proviral DNA of human spumaretrovirus, various recombinant clones were established and analyzed. Blot hybridization revealed that one of the recombinant plasmids had the characteristic features of a member of the long interspersed repetitive sequences family. The DNA element was analyzed by restriction mapping and nucleotide sequencing. It showed a high degree of amino acid sequence homology of 54.3% when compared with the 5'-terminal part of the pol gene product of the murine retrotransposon LIMd. The 3' region of the cloned DNA element encodes proteins with an even higher degree of homology of 67.4% in comparison to the corresponding parts of a member of the primate KpnI sequence family.
Subject(s)
Cloning, Molecular , DNA Transposable Elements , DNA/analysis , Retroviridae/genetics , Amino Acid Sequence , Base Sequence , Cell Line , DNA Restriction Enzymes , Humans , Lung/embryology , Sequence Homology, Nucleic AcidABSTRACT
The thymidine kinase (TK) gene of fish lymphocystis disease virus (FLDV) was identified by biochemical transformation of 3T3 TK negative (TK-) to 3T3 TK positive (TK+) cells using specific viral DNA sequences. DNA fragments of the viral genome used in this study were obtained from a defined gene library of FLDV genome containing the complete viral DNA sequences. The selection of the converted cells was carried out under the condition of the HAT selection procedure. The results of these experiments revealed that the EcoRI FLDV DNA fragment C (11.2 kbp; 0.611 to 0.718 map units) is able to transform 3T3 TK- to 3T3 TK+ cells. Additional experiments using the subclones of EcoRI DNA fragment C revealed that DNA sequences of 4.1 kbp size between the coordinates 0.669 to 0.718 of the FLDV genome possessed the ability for biochemical transformation, indicating that the TK gene locus is located in this particular region.
Subject(s)
Iridoviridae/genetics , Thymidine Kinase/genetics , Viral Proteins/genetics , Animals , DNA, Viral/genetics , Fibroblasts , Iridoviridae/enzymology , Mice , Recombinant Proteins , TransfectionABSTRACT
Recombinant glyceraldehyde-3-phosphate dehydrogenase of the cestode parasite Echinococcus multilocularis was expressed in Escherichia coli and in Salmonella typhimurium. The potential of different forms of the recombinant antigen to protect BALB/c mice against oral challenge infections with E. multilocularis eggs was evaluated. Oral or intraperitoneal immunisation with live attenuated S. typhimurium as a carrier for recombinant glyceraldehyde-3-phosphate dehydrogenase of the E. multilocularis resulted in significant protection, reducing the number of developing metacestodes up to 79.8%. The sera of protected animals did not contain detectable amounts of antibody against glyceraldehyde-3-phosphate dehydrogenase of E. multilocularis. By contrast, although anti-glyceraldehyde-3-phosphate dehydrogenase of E. multilocularis antibodies were detectable in the sera, immunisation with E. coli-expressed recombinant glutathione-S-transferase-fusion protein or with glyceraldehyde-3-phosphate dehydrogenase of E. multilocularis fused to a 6HIS-tag failed to protect the animals against oral challenge infections. These data emphasise that antigen delivery systems play a critical role in vaccination and the induction of protective immunity against helminth parasites.
Subject(s)
Echinococcosis/immunology , Echinococcus/immunology , Glyceraldehyde-3-Phosphate Dehydrogenases/immunology , Immunization , Amino Acid Sequence , Animals , Base Sequence , Blotting, Western , Cloning, Molecular , Echinococcosis/parasitology , Echinococcosis/prevention & control , Echinococcus/enzymology , Escherichia coli/enzymology , Escherichia coli/genetics , Female , Glyceraldehyde-3-Phosphate Dehydrogenases/biosynthesis , Glyceraldehyde-3-Phosphate Dehydrogenases/genetics , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Salmonella typhimurium/enzymology , Salmonella typhimurium/genetics , Sequence Homology, Amino Acid , Statistics, NonparametricABSTRACT
To investigate whether the recently discovered hepatitis G virus (HGV) influences the clinical outcome of heart transplant recipients under immunosuppression, we determined the prevalence of HGV infections correlated with liver function and survival in 51 patients. Presence of HGV RNA and anti-E2, a marker for resolved HGV infection, were serially tested in sera from patients before and after heart transplantation (HTX) by nested RT-PCR and ELISA. Four of 51 (7.8%) patients before transplantation, and 22 of 50 patients (44%) after transplantation showed signs of persistent or resolved HGV infection. HGV infection was not associated with impairment of liver function or with patient survival. In summary, presence of HGV infection does not influence the clinical outcome in heart transplant patients.
Subject(s)
Flaviviridae , Heart Transplantation , Hepatitis, Viral, Human/diagnosis , Enzyme-Linked Immunosorbent Assay , Female , Flaviviridae/isolation & purification , Graft Rejection , Hepatitis, Viral, Human/physiopathology , Humans , Liver Function Tests , Male , Middle Aged , Polymerase Chain Reaction , RNA, Viral/analysis , Retrospective Studies , Viral Envelope Proteins/analysisABSTRACT
Microbial agents may play a role in the pathogenesis of multiple sclerosis (MS). C. pneumoniae has been recently associated with MS; however, study results are at variance. We tested the hypothesis that Chlamydia pneumoniae-specific DNA and RNA are more often detected in cerebrospinal fluid (CSF) of patients with multiple sclerosis than patients with other neurological diseases (OND). We investigated CSF samples from 84 patients with definite MS and 89 OND patients (n = 62 with normal CSF; n = 27 with pathological CSF) using a nested polymerase chain reaction (PCR) to detect ompA gene sequences of C. pneumoniae. In subjects with positive PCR, we probed for chlamydial heat shock protein 60-mRNA and 16S-rRNA by reverse transcriptase (rt)-PCR. C. pneumoniae-specific DNA was more often detected in MS patients (50 %) than in all OND patients combined (28.1%, p = 0.003) and in OND patients with normal CSF (24.2%, p = 0.003) but not than in OND patients with pathological CSF (37%, p = 0.24). In relapsing-remitting MS (n = 55), the prevalence of C. pneumoniae DNA was higher (66.7 %) than in both OND subgroups (p Subject(s)
Chlamydia Infections/complications
, Chlamydophila pneumoniae/genetics
, DNA, Viral/cerebrospinal fluid
, Multiple Sclerosis, Relapsing-Remitting/complications
, Adult
, Bacterial Outer Membrane Proteins/genetics
, Bacterial Outer Membrane Proteins/metabolism
, Blotting, Northern/methods
, Chlamydia Infections/epidemiology
, Chlamydia Infections/genetics
, Chlamydophila pneumoniae/isolation & purification
, Female
, Heat-Shock Proteins/genetics
, Heat-Shock Proteins/metabolism
, Humans
, Male
, Middle Aged
, Multiple Sclerosis, Relapsing-Remitting/cerebrospinal fluid
, Multiple Sclerosis, Relapsing-Remitting/genetics
, Multiple Sclerosis, Relapsing-Remitting/microbiology
, Nervous System Diseases/cerebrospinal fluid
, Nervous System Diseases/epidemiology
, Nervous System Diseases/genetics
, Nervous System Diseases/virology
, Prevalence
, RNA, Messenger/biosynthesis
, Reverse Transcriptase Polymerase Chain Reaction/methods