Intervirology (INTERVIROLOGY)

Publications in this journal

• Article: Chimeric potyvirus-like particles as vaccine carriers. M N MN Jagadish, S J SJ Edwards, M B MB Hayden, J J Grusovin, K K Vandenberg, P P Schoofs, R C RC Hamilton, D D DD Shukla, H H Kalnins, M M McNamara, J J Haynes, I T IT Nisbet, C W CW Ward, D D Pye Intervirology 39(1-2):85-92 (1996), PMID 8957674

  M N MN Jagadish, S J SJ Edwards, M B MB Hayden, J J Grusovin, K K Vandenberg, P P Schoofs, R C RC Hamilton, D D DD Shukla, H H Kalnins, M M McNamara, J J Haynes, I T IT Nisbet, C W CW Ward, D D Pye Intervirology, PMID
  [show abstract] [hide abstract]
  ABSTRACT: Presentation of subunit vaccines in a highly ordered aggregate form can result in enhanced immune responses. Coat protein (CP) monomers of a potyvirus (Johnsongrass mosaic virus) when produced in heterologous host expression systems (Escherichia coli, yeast and insect cells) self-polymerized to produce potyvirus-like particles (PVLPs). The N- and C-terminal regions of potyvirus CP are surface-exposed and are not required for assembly. Hybrid CP monomers containing short peptides fused to their N- and/or C-termini, or large target antigens fused to the N-terminus or replacing most of the N- or C-terminal exposed regions retained the ability to assemble into hybrid PVLPs. Such chimeric PVLPs were highly immunogenic in mice and rabbits even in the absence of any adjuvant. Potyvirus CP is highly versatile in accommodating peptides or large antigens and is able to present antigens exposed on the surface of virus-like particles. This, combined with the efficiency of high level bacterial and insect cell expression systems, makes PVLPs an attractive non-pathogenic and non-replicative vaccine carrier.
  Intervirology 02/2013; 39((1-2)):85-92.
• Article: Isolation of a novel adenovirus from Rousettus leschenaultii bats from India

  Raut CG, Yadav PD, Towner JS, Amman BA, Erickson BR, Cannon DL, Sivaram A, Basu A, Nichol ST, Mishra AC1and Mourya DT
  Intervirology 05/2012;
• Article: Induction of Antibodies Binding to the Membrane Proximal External Region of gp36 of HIV2

  R. Behrendt, U. Fiebig, R. Kurth, J. Denner
  [show abstract] [hide abstract]
  ABSTRACT: Objective: The ability to induce neutralizing antibodies may be the most important feature of an antiretroviral vaccine, preventing infection of target cells and subsequent integration of the virus into the cellular genome where the virus may persist. Broadly neutralizing antibodies directed against conserved epitopes in the membrane proximal external region (MPER) of the transmembrane envelope (TM) protein gp41 of HIV-1 such as the monoclonal antibodies (mAb) 2F5 and mAb 4E10 have been found in infected individuals; however, all attempts to induce such antibodies failed. In individuals infected with HIV-2 such antibodies were not yet reported. Methods: Two recombinant proteins corresponding to the ectodomain of the TM protein gp36 of HIV-2 were produced, rats were immunized and sera were analyzed for binding and neutralizing antibodies. Results: Although binding antibodies were induced, none of the sera neutralized HIV-2. Most interestingly, epitope mapping showed specific binding of the antibodies to the MPER of gp36, to a region homologous to the binding site of the mAb 4E10 in gp41 of HIV-1. Conclusions: Although MPER-specific antibodies were induced by vaccination with gp36, these antibodies did not neutralize HIV-2. This is similar to the situation with HIV-1, but in contrast to that with gammaretroviruses.Copyright © 2011 S. Karger AG, Basel
  Intervirology 01/2012; 55:252-256.
• Article: Special Aspects of the Treatment of HIV2Infected Patients

  Ricardo Jorge Camacho
  [show abstract] [hide abstract]
  ABSTRACT: HIV-2 is responsible for a limited epidemic in West Africa. Around 20% of all infected patients will progress to AIDS, and will need antiretroviral therapy. Unfortunately, antiretrovirals were developed to suppress HIV-1 replication; not all of them are active against HIV-2, e.g. all nonnucleoside reverse transcriptase inhibitors or fusion inhibitors. Moreover, only three protease inhibitors have the same activity in HIV-1 and HIV-2: lopinavir, saquinavir and darunavir. Even if all nucleoside and nucleotide reverse transcriptase inhibitors appear to be equally efficient against HIV-2, different resistance pathways and an increased facility of resistance selection make their use much more difficult than in HIV-1. Integrase inhibitors have a potent inhibitory effect on HIV-2 replication, but questions about the best timing for their use remain unanswered, as well as those regarding the use of entry inhibitors in this setting. The lack of reliable monitoring tools adds to the difficulty of treating HIV-2-infected patients, mostly because the viral load is not as useful as it is in HIV-1, and the incomplete knowledge about resistance pathways limits the clinical usefulness of resistance testing. With all these limitations, HIV-2 treatment remains a challenge. Further research is urgently needed, since antiretroviral therapy is now becoming available in countries where the HIV-2 prevalence is significant. The need for appropriate guidelines for HIV-2 treatment has become an emergency.Copyright © 2012 S. Karger AG, Basel
  Intervirology 01/2012; 55:179-183.
• Article: Intrahepatic mRNA levels of type I interferon receptor and interferon-stimulated genes in genotype 1b chronic hepatitis C. Association between IFNAR1 mRNA level and sustained response to interferon therapy.

  Hideaki Taniguchi, Yoshiaki Iwasaki, Akira Takahashi, Hiroyuki Shimomura, Akio Moriya, Piao Cheng Yu, Fumi Umeoka, Shin-ichi Fujioka, Norio Koide, Yasushi Shiratori
  [show abstract] [hide abstract]
  ABSTRACT: The aim of this study was to determine the association between pretreatment intrahepatic mRNA levels of interferon receptor and interferon-stimulated genes and response to interferon therapy for genotype 1b chronic hepatitis C. Forty-four patients with genotype 1b chronic hepatitis C who underwent liver biopsy and then received interferon therapy participated in this study. Pretreatment intrahepatic mRNA levels of interferon receptor genes (IFNAR1, IFNAR2b, and IFNAR2c) and interferon-stimulated genes (OAS1 and PKR) were quantified by competitive polymerase chain reaction. In the genes examined, only IFNAR1 mRNA level was significantly higher in patients with sustained virological and biochemical response to interferon therapy versus those with nonsustained response (p < 0.01). Moreover, mRNA expression ratios of IFNAR1 to IFNAR2 were also significantly higher in patients with sustained virological and biochemical response to IFN therapy (p < 0.01 and p < 0.05, respectively). On the other hand, mRNA levels of IFNAR2b, IFNAR2c, and PKR were significantly higher in patients with histologically active or advanced liver rather than patients with mild or less advanced liver. Conclusions: High intrahepatic mRNA levels of IFNAR1 and mRNA ratio of IFNAR1 to IFNAR2 before treatment may be associated with a favorable response to interferon therapy.
  Intervirology 02/2007; 50(1):32-9.
• Article: A new algorithm for deduction of hepatitis B surface antigen subtype determinants from the amino acid sequence.

  Michael A Purdy, Ganesh Talekar, Paul Swenson, Aufra Araujo, Howard Fields
  [show abstract] [hide abstract]
  ABSTRACT: We have reexamined hepatitis B virus subtypes to determine the role of specific HBsAg amino acids in serologic reactivity because of problematic genotype/subtype associations seen in a set of geographically diverse serum specimens. We obtained DNA sequences for 491 HBsAg-positive specimens from geographically distinct locations, determined their genotypes through phylogenetic analysis, and subtyped the specimens using an algorithm derived from published data on the molecular basis of HBsAg subtype reactivity. Problematic samples were subtyped serologically to resolve conflicts based on the amino acid sequence alone. Three isolates were found to have unusual genotype/subtype associations. Examination of the isolates' amino acid sequences suggested amino acid positions 122, 127, 140, 159 and 160 can be used to determine subtype reactivity from HBsAg amino acid sequences, while position 134, previously thought to play a role, is no longer important. This re-examination of hepatitis B virus subtypes shows the involvement of amino acid positions 122, 127, 140, 159 and 160 in HBsAg reactivity. While d, y, and r reactivities are controlled by single amino acid changes, w reactivity is determined by positions 122, 127, 140, and 159.
  Intervirology 02/2007; 50(1):45-51.
• Article: Cross-protection against homologous drift variants of influenza A and B after vaccination with split vaccine.

  R Heckler, A Baillot, H Engelmann, E Neumeier, A Windorfer
  [show abstract] [hide abstract]
  ABSTRACT: The aim of this serological study was to demonstrate the extent to which antibodies react against subsequent drift variants, after vaccination with split vaccine (Fluarix). Antibody titers have been determined by hemagglutination inhibition test (HI) against different influenza A and B drift variants in sera from three past multicenter trials. Individuals of two different age groups, i.e. 18-60 years and above 60 years, were enrolled. Vaccine components influenza A/H1N1 and influenza B of Fluarix show a high degree of cross immunogenicity against subsequent homologous drift variants. The genetically more variable component influenza A/H3N2 shows somewhat lower protection rates. High levels of cross immunogenicity were found between the variants of influenza A/Panama/2007/99 (H3N2) and influenza A/Wyoming/3/2003 (H3N2). The results demonstrate that in situations where drift variants emerge too late to be included in the influenza vaccine formulation, the cross-protection conferred must be evaluated on a case-by-case basis.
  Intervirology 02/2007; 50(1):58-62.
• Article: Carboxyl-terminal sequence variation of latent membrane protein 1 gene in Epstein-Barr virus-associated gastric carcinomas from Eastern China and Japan.

  Yun Wang, Kyosuke Kanai, Yukio Satoh, Bing Luo, Takeshi Sairenji
  [show abstract] [hide abstract]
  ABSTRACT: To elucidate variations of latent membrane protein 1 (LMP1) in Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and explore the LMP1 variations of neighboring countries, China and Japan. In 12 and 8 EBVaGCs from eastern China and Japan, respectively, the C-termini of LMP1 were analyzed using PCR and sequencing. The sequences were compared with previously published strains and were characterized on a phylogenetic tree. The difference between Chinese and Japanese isolates was characterized. Ten of 12 Chinese GC isolates (83.3%) and all of the 8 (100%) Japanese GC isolates belonged to the China 1 strain. Also, B95-8 type isolates were found in 2 of 12 Chinese GC. In the 18 China 1 type isolates, additional mutations outside the signature sequence changes were found. All Japanese isolates (100%) had two or more additional mutations, whereas only 5 of 10 (50%) Chinese isolates had two or more additional mutations. The difference was statistically significant (p = 0.0359). China 1 is the dominant strain in GC from eastern China and Japan. The similarity to that of nasopharyngeal carcinoma (NPC) from China supports the view that China 1 strain represents a geographic-associated polymorphism rather than an NPC-associated polymorphism. Japanese isolates show more mutations than Chinese isolates, suggesting a geographic difference between Chinese and Japanese isolates in GC.
  Intervirology 02/2007; 50(3):229-36.
• Article: Susceptibility of mouse macrophage J774 to dengue virus infection.

  María M B Moreno-Altamirano, F Javier Sánchez-García, Martha Legorreta-Herrera, Israel Aguilar-Carmona
  [show abstract] [hide abstract]
  ABSTRACT: The aim of this study was to investigate whether the J774 mouse macrophage cell line could be used as an in vitro model for dengue virus infection (DENV). After 3 days, infection in J774 cells was assessed by detecting dengue virus non-structural protein 1 (NSP-1) production either by dot blot or indirect immunofluorescence assay (IFA) of saponine-permeabilized J774 cells and then confirmed by RT-PCR (171 bp product, corresponding to the DENV-2 core). Based on the presence of NSP-1 in infected but not in non-infected cells by both IFA and dot blot, as well as the amplification of a 171-bp DENV-2-specific RT-PCR product exclusively in the infected cells, the J774 cell line was found to be permissive for dengue virus infection. As far as we know, this is the first report that the J774 mouse macrophage cell line is infected with dengue virus and, thus, that it can be used as an alternative in vitro model for dengue virus infection studies. This finding could help to further elucidate the mechanisms involved in dengue virus infection and pathogenesis.
  Intervirology 02/2007; 50(3):237-9.
• Article: Seroprevalence of hepatitis B and C viruses in patients with chronic kidney disease in the predialysis stage at a university hospital in Turkey.

  Dede Sit, Ali Kemal Kadiroglu, Hasan Kayabasi, M Emin Yilmaz, Vedat Goral
  [show abstract] [hide abstract]
  ABSTRACT: Hepatitis B (HBV) and C (HCV) viruses are the most common viruses that cause viral infections among the hemodialysis patients. To assess the prevalence of HBV and HCV in predialytic chronic kidney disease (CKD) patients. A cross-sectional study. 171 consecutive predialytic CKD patients. Third-generation micro-ELISA assay was used for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core (anti-HBc) and surface antibody (anti-HBs), secretory form of hepatitis B envelop antigen (HBeAg), antibody to secretory form of hepatitis B envelop antigen (anti-HBe), and ELISA for antibody to hepatitis C virus (anti-HCV). The main causes of CKD were 29.8% diabetic nephropathy, 19.9% chronic glomerulonephritis, 16.3% hypertensive nephrosclerosis, 14.0% unknown, 5.3% amyloidosis, 4.7% autosomal-dominant polycystic kidney disease, 4.1% chronic tubuluointerstitial nephritis, 3.5% malignancies, 1.7% benign prostatic hypertrophy, 0.6% Alport syndrome. The seroprevalence of hepatitis was: HBsAg 10.5%, anti-HBc 36.8%, anti-HBs 28.7%, HBeAg 5.3%, anti-HBe 32.7%, anti-HCV 7% and HBsAg+anti-HCV 0.6%. The seroprevalence of HBsAg and anti-HCV among predialytic CKD patients was similar to our patients in hemodialysis program.
  Intervirology 02/2007; 50(2):133-7.
• Article: The synergistic interaction of interferon types I and II leads to marked reduction in severe acute respiratory syndrome-associated coronavirus replication and increase in the expression of mRNAs for interferon-induced proteins.

  Carolina Scagnolari, Simona Trombetti, Alessia Alberelli, Simona Cicetti, Daniela Bellarosa, Roberta Longo, Alberto Spanò, Elisabetta Riva, Massimo Clementi, Guido Antonelli
  [show abstract] [hide abstract]
  ABSTRACT: Interferon (IFN)-alpha, -beta and -gamma have been shown to be only marginally effective against severe acute respiratory syndrome coronavirus (SARS-CoV) replication in Vero cell lines. We investigated the combination of type I IFNs (IFN-alpha or -beta) and IFN-gamma for antiviral activity and found that such combinations synergistically inhibited SARS-CoV replication in Vero cells, using yield reduction assay and the isobologram and combination index methods of Chou and Talalay for evaluation. The highly synergistic anti-SARS-CoV action of type I IFNs and IFN-gamma parallels the marked increase in 2'-5'-oligoadenylate synthetase and p56 mRNAs following exposure in Vero cells to either IFN-alpha or -beta and IFN-gamma compared with the transcriptional levels obtained after stimulation with either IFN alone. These results demonstrate that SARS-CoV, although only moderately sensitive to the antiviral action of the individual types of IFN, is highly sensitive to a combination of type I and II IFNs, which suggests that such combinations may have potential in the treatment of SARS-CoV infections.
  Intervirology 02/2007; 50(2):156-60.
• Article: Compositional bias and size of genomes of human DNA viruses.

  Jaturong Sewatanon, Sirawat Srichatrapimuk, Prasert Auewarakul
  [show abstract] [hide abstract]
  ABSTRACT: Genomes of 144 human DNA viruses were analyzed in the aspect of their compositional asymmetry. DNA viruses were divided into two groups according to their genome sizes. The analysis revealed that the level of guanine and cytosine (GC content) in the coding sequences of small genome DNA viruses was significantly lower than that of large genome DNA viruses. Because small genome viruses replicate their genomes using cellular enzymes, while large genome viruses use their own enzymes for genome replication, the two groups of viruses may be under different mutational bias and/or selection pressure. In these viruses, GC content at the third codon position correlated with GC content at the first and second codon position. However, the relationship in small genome DNA viruses was weaker than that in large genome DNA viruses, suggesting that their genome composition may be more strongly influenced by codon usage preference or restriction on amino acid composition.
  Intervirology 02/2007; 50(2):123-32.
• Article: Intra- and intergenotypic variations among human cytomegalovirus gB genotypes.

  S Chantaraarphonkun, P Bhattarakosol
  [show abstract] [hide abstract]
  ABSTRACT: To study genotypic variations among human cytomegalovirus (HCMV) gB genotypes in clinical samples of Thai patients. gB genotyping of 31 HCMV-DNA-positive clinical samples were determined by PCR-RFLP, gene cloning and DNA sequencing methods. Eight gB1, 7 gB2, 7 gB3, 6 gB untype (UT1 and UT2) and 3 mixed gB genotypes were first identified by PCR-RFLP. All 3 mixed gB genotype samples and 1 gB2 sample were cloned and confirmed gB genotype by PCR-RFLP. Altogether, 57 strains (27 unique types and 30 transformants) were further analyzed by DNA sequencing method. Discordant results between PCR-RFLP and DNA sequencing methods were demonstrated in 5 samples and 1 clone. The gB UT1 and UT2 were all classified as gB1 except 1 sample of UT1 (9D), suggesting a new variant. Each genotype had a similarity of more than 97%, whereas strains of different genotypes had 77.71-92.75% homology. The most divergent type was gB3. Intra- and intergenotypic variations among strains were demonstrated either in individual or distinct patients. Intragenotypic variation in a person occurs possibly due mainly to a point mutation mechanism rather than reinfection of a new gB genotype.
  Intervirology 02/2007; 50(2):78-84.
• Article: Entry into and production of the Japanese encephalitis virus from C6/36 cells.

  Verawan Boonsanay, Duncan R Smith
  [show abstract] [hide abstract]
  ABSTRACT: The mosquito-borne Japanese encephalitis virus is a leading cause of encephalitis worldwide. However, few studies have investigated the kinetics of Japanese encephalitis virus internalization and production in mosquito cells, and fewer still have investigated the nature of the molecules involved in the binding of the virus to mosquito cells. Using the Aedes albopictus/Stegomyia albopicta-derived C6/36 cell line, Japanese encephalitis virus internalization and production were assayed by standard plaque assay, and virus binding was investigated through preinfection enzymatic treatment of cells and virus overlay protein-binding assay of membrane fractions in native and denaturing gels. The internalization of the virus was nonlinear, and intracellular infective viruses were detected 8 h after infection and exported to the medium 10 h after infection. The internalization of the virus was primarily mediated by protein elements, and several bands were observed after overlay assay to membrane proteins, although mass spectroscopy was unable to identify candidate proteins. Soluble laminin produced a marginal, but dose-dependent inhibition of infection. These results suggest that the mechanism of Japanese encephalitis entry, production, attachment and receptor usage are distinct from those employed by the dengue viruses.
  Intervirology 02/2007; 50(2):85-92.
• Article: Long-term outcome after interferon therapy in elderly patients with chronic hepatitis C.

  Yasuji Arase, Kenji Ikeda, Fumitaka Suzuki, Yoshiyuki Suzuki, Satoshi Saitoh, Masahiro Kobayashi, Norio Akuta, Takashi Someya, Rikako Koyama, Tetsuya Hosaka, Hitomi Sezaki, Mariko Kobayashi, Hiromitsu Kumada
  [show abstract] [hide abstract]
  ABSTRACT: The purpose of this study was to elucidate the long-term outcome after interferon (IFN) therapy in chronic hepatitis C elderly patients. We studied the incidence of hepatocellular carcinoma (HCC) and survival probability after the initiation of IFN therapy in 500 Japanese chronic hepatitis C patients >60 years. The mean age of initiation of IFN was 63 years and the mean follow-up period was 7.4 years. Cox proportional hazard regression analysis was used to evaluate the long-term outcome after initiation of IFN therapy. Sustained virological response (SVR) was defined as negative HCV-RNA by RT-nested PCR 6 months after the completion of long-term IFN therapy. Non-response (NR) was applied to patients who did not show SVR. Hepatic fibrosis was defined as the fibrosis score (score 0-4) according to Knodell et al. 140 patients (28%) had an SVR and 360 patients (72%) had an NR. 71 of 500 patients developed HCC during follow-up. The cumulative incidence of HCC was 9.6% at the 5th year, 17.4% at the 10th year, and 31.3% at the 15th year. HCC developed with significance when: (1) HCV was not cleared after IFN therapy (p < 0.0001), (2) sex was male (p < 0.0001), and (3) staging of liver fibrosis was >2 (p = 0.008). 53 of the patients died. The cumulative survival probability was 95.7% at the 5th year, 86.4% at the 10th year, and 78% at the 15th year. Patients achieved a long survival with significance when: (1) staging of liver fibrosis was 1 (p < 0.0001), (2) HCV was cleared after IFN therapy (p = 0.034), and (3) sex was female (p = 0.015). Chronic hepatitis C patients with clearance of HCV after IFN therapy had a significantly reduced risk of HCC appearance and achieved prolonged survival even if they are > or =60 years.
  Intervirology 02/2007; 50(1):16-23.
• Article: Reliable generation of stable high titer producer cell lines for gene therapy.

  Ina Rattmann, Veronika Kleff, Anja Feldmann, Carsten Ludwig, Ursula Regina Sorg, Bertram Opalka, Thomas Moritz, Michael Flasshove
  [show abstract] [hide abstract]
  ABSTRACT: Retroviral vectors represent one of the most robust technologies for in vivo expression of heterologous gene sequences and are still the most commonly used vectors in clinical gene therapy trials. The production of high titer retroviral preparations, however, can be a problematic procedure for certain constructs. GALV- or RD114-pseudotyped retroviral particles carrying selectable fluorescence markers or drug resistance genes, such as the green fluorescent protein (GFP) or the O(6)-methylguanine-DNA-methyltransferase (MGMT) mutants, were used to stably transduce Phoenix-(FNX-)eco cells. Thereafter, a polyclonal population of producer cells was generated by enriching cells with high marker gene expression. In addition, single producer clones were selected by limiting dilution. Retroviral titers were increased 1-2 logs by enriching for a polyclonal population of producer cells, and selection of single producer clones allowed another 1- to 2-log increase in titers. Using this method, reproducibly high titer viral preparations allowing efficient transduction of hematopoietic stem cells were generated. A reliable and time-effective method to generate stable high titer producer cells based on the FNX-cell line for problematic retroviral vector constructs is described.
  Intervirology 02/2007; 50(3):197-203.
• Article: G1862T mutation among hepatitis B virus-infected individuals: association with viral genotypes and disease outcome in Kolkata, Eastern India.

  Partha K Chandra, Arup Banerjee, Sibnarayan Datta, Runu Chakravarty
  [show abstract] [hide abstract]
  ABSTRACT: To study the prevalence of G1862T mutation in hepatitis B virus (HBV) isolates among Eastern Indian patients and its relationship with genotypes, HBeAg status and disease manifestation. HBV DNA was isolated from patients, amplified by nested PCR and sequenced directly. Of the 102 patients, 32 were HBeAg positive and 70 HBeAg negative; 55, 24 and 23 isolates were infected with genotypes D, A and C, respectively. G1862T was detected in 18 samples, 15 (83%) of them belonged to genotype A (subgenotype HBV/A1), 3 (17%) to genotype D. This mutation was more frequent in HBeAg-negative than in HBeAg-positive patients (21 vs. 9%), whereas in HBV/A1 it was as common in HBeAg-positive as in HBeAg-negative patients and significantly associated with T1762/A1764 mutation. The mean viral load was lower in patients with G1862T mutation. Furthermore, this mutation was common in various clinical outcomes. In our community, G1862T mutation was predominantly found in HBV/A1 isolates irrespective of HBeAg status. Moreover this mutation could not be correlated to the clinical outcome. These findings indicate that the G1862T mutation is probably a part of the natural variability of HBV/A1.
  Intervirology 02/2007; 50(3):173-80.
• Article: Effects of ectodomain sequences between HR1 and HR2 of F1 protein on the specific membrane fusion in paramyxoviruses.

  Guijie Ren, Zhiyu Wang, Xiaoyan Hu
  [show abstract] [hide abstract]
  ABSTRACT: To explore the effects of ectodomain sequences between HR1 and HR2 of F1 protein on the specific interaction with its homologous hemagglutinin-neuraminidase (HN) in paramyxoviruses. Site-directed mutagenesis was used to obtain mutants containing new enzyme sites on the F genes of Newcastle disease virus (NDV) and human parainfluenza virus (hPIV), and four DNA segments located between the HR1 and HR2 (NDV F-1, hPIV F-1, NDV F-2 and hPIV F-2) were obtained by cutting mutant F genes with specific endonucleases. Gene recombination was used to get chimeric F proteins NDV-C1 and hPIV-C1 by exchanging NDV F-1 and hPIV F-1 each other, and NDV-C2 and hPIV-C2 were also obtained by the same way. All the mutants and chimeric F proteins were co-expressed with their homologous or heterologous HN proteins in eukaryocytes. The fusion functions were assayed with Giemsa staining and reporter gene method for qualitative and quantitative analyses, respectively. The cell surface expression of F proteins was assayed with fluorescence-activated cell sorter (FACS) for quantitative analysis. All the mutants of F proteins had the same functions as their relevant wild types. Chimeric F proteins NDV-C1 and hPIV-C1 had 76.34 and 65.82% of fusion activities, and NDV-C2 and hPIV-C2 had 96.25 and 93.78% of fusion activities, respectively, as compared with their relevant wild types. The analysis of FACS indicated that all the mutants and chimeric F proteins had almost the same expression efficiencies as their relevant wild types. The segments of NDV F-1 and hPIV F-1 were important for their specific membrane fusion, but NDV F-2 and hPIV F-2 were not.
  Intervirology 02/2007; 50(2):115-22.
• Article: Phylogenetic analysis of echovirus 11 in the 3' end of the VP1.

  Lamjed Bouslama, Dorra Rezig, Ahlem Ben Yahia, Mahjoub Aouni, Hinda Triki
  [show abstract] [hide abstract]
  ABSTRACT: Echovirus 11 is one of the most frequently isolated enterovirus serotypes, causing a wide range of clinical diseases. We studied the genetic diversity in the 3' end of the VP1 gene of strains from different geographical origin in the world. The sequences in the 3' end of the VP1 of 11 Tunisian isolates were determined and aligned with the published sequences to establish a phylogenetic profile. The grouping of the sequences was similar to what was previously reported by analyzing the whole VP1 gene with 4 genogroups, designated A-D, and 5 lineages in genogroup D. All Tunisian strains belonged to genogroup D, together with other sequences mainly from the USA and Europe. Contrary to the sequences from the USA isolated during the last 3 decades, which mostly belonged to the D4 lineage, those from Tunisia belonged to different lineages within genogroup D according to their isolation date: isolates from the early 1990s belonged to D3, those of the mid 1990s to D4 and the most recent ones to D5. Our findings further widen the interest of partial sequencing in the VP1 to study the molecular epidemiology of echovirus 11 and indicate that the genetic evolution of circulating strains may differ from one country to another according to the region's epidemiological specificities.
  Intervirology 02/2007; 50(2):108-14.