Electronic Library of Scientific Literature
Volume 42 / October 1998 / number 5
H. LIPTÁKOVÁ, E. KONTSEKOVÁ, P. KABÁT, V. HAJNICKÁ, M. OLTMAN, D. STANČEK, N. FUCHSBERGER, P. KONTSEK
Institute of Virology, Slovak Academy of Sciences, Dúbravská cesta 9,
842 42 Bratislava;
Department of Microbiology and Virology, Comenius University, Bratislava;
Institute of Preventive and Clinical Medicine, Bratislava, Slovak Republic
Summary. - Fifty-eight patients with chronic hepatitis B (HB) or C (HC) were treated with recombinant human interferon (rIFN)-alpha 2 and their sera were assayed for antibodies to rIFN-alpha 2c. Twelve of these patients produced low titres and two high titres of the antibodies. We localised the region which was recognised by the high-titre therapy-induced antibodies on the IFN molecule by testing the antibodies with a set of murine monoclonal antibodies (MoAbs) to IFN-alpha 2 in a competitive radioimmune assay (RIA). Only MoAbs with epitopes located in the amino-terminal portion of IFN-alpha 2 could inhibit the binding of radiolabelled IFN-alpha 2 by patients' sera. Our data indicate that the therapy-induced antibodies were directed to the receptor-binding domain of IFN-alpha 2 formed by amino acids (aa) 30-53. In accordance with this observation, human anti-IFN sera inhibited the binding of rIFN-alpha 2 to human cells.
Key words: hepatitis B and C; interferon-alpha 2; therapy; antibodies;
Acta virologica 42: 279 - 284, 1998
M. SHIKATA, M. NAKAGAWA, Y. SANO, T. MATSUMOTO, Y. HASHIMOTO
Department of Applied Biology, Faculty of Textile Science, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
Summary. - A temperature-sensitive (ts) mutant of bombyx mori nucleopolyhedrovirus (BmNPV), ts-S1, contains a mutation in a putative RNA polymerase gene, which is involved in late viral gene expression. When 4th-instar silkworm larvae were infected with 1.0 x 105 TCID50 of ts-S1 per larva and reared at 33°C, the titre of budded virus (BV) and number of occlusion bodies (OBs) in the haemolymph of the infected larvae were very low in the early stage but markedly increased in the late stage of infection. In contrast, a rapid increase in both BV titre and OB number was detected in the haemolymph of infected larvae reared at 25°C. LD50 values of ts-S1 and wild type BmNPV (wtBmNPV) for 4th-instar larvae were 2.41 and 0.96 TCID50 per larva at 25°C, and >1.0 x 106 and 1.70 TCID50 per larva at 33°C, respectively. These results indicate that the virulence of ts-S1 for the larvae reared at 33°C was markedly reduced. To examine further the reduction of ts-S1 virulence at the non-permissive temperature of 33°C, silkworm larvae were infected with ts-S1 at the multiplicity of 1.0 x 102 - 1.0 x 106 TCID50 per larva, reared for various time at 33°C and then shifted to 25°C. Longer rearing periods at 33°C resulted in better survival rates indicating that the reduction of virulence of ts-S1 was proportional to cumulative rearing time at 33°C. When large virus inocula were used, a growth alteration of larvae was preferentially induced. However, when small virus inocula were used, the appearance of abortive infection due to the non-permissive temperature became more evident.
Key words: bombyx mori nucleopolyhedrovirus; silkworm larvae;
temperature-sensitive mutant; virulence; abortive infection
Acta virologica 42: 285 - 292, 1998
T. YANASE, C. YASUNAGA, T. KAWARABATA
Institute of Biological Control, Faculty of Agriculture, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan
Summary. - The Spodoptera exigua multinucleocapsid nucleopolyhedrovirus (SeMNPV) was inoculated to eight lepidopteran cell lines derived from Spodoptera exigua (Se301), Spodoptera frugiperda (SF21AEII), Spodoptera littoralis (CLS-79), Spodoptera litura (SpLi-221), Pseudaletia separata (LeSe-11), Trichoplusia ni (hi-5), Plutella xylostella (PXL/C) and Bombyx mori (BmN4). The productive infection of SeMNPV was observed only in Se301 cells. However, a dot-blot hybridization analysis revealed that SeMNPV DNA replicated in five non-permissive cell lines: SF21AEII, CLS-79, SpLi-221, hi-5 and BmN4. In addtion, the virus-infected hi-5 and BmN4 cells displayed morphological changes. In contrast, CLS-79 cells inoculated with SeMNPV showed membrane blebbing at 20 hrs post inoculation (p.i.) and fragmentation of genomic DNA. All that indicated that the infected CLS-79 cells underwent apoptosis. These findings indicate that the SeMNPV replication was restricted at various points in dependence upon each cell line.
Key words: Spodoptera exigua; baculovirus; nuclear polyhedrosis
virus; host specificity; apoptosis; insect cell line
Acta virologica 42: 293 - 298, 1998
L.R. DEVIREDDY, R. RAGHAVAN, S. RAMACHANDRAN , S.M. SUBBARAO
Department of Veterinary Microbiology, Veterinary College, Bangalore,
560 024, India;
Centre for Tropcial Veterinary Medicine, University of Edinburgh, Roslin, Midlothian, Scotland, U.K.;
Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, 560 012, India
Summary. - Haemagglutinin (HA) and fusion (F) proteins of peste-des-petits-ruminants virus (PPRV) and rinderpest virus (RPV) were purified by immunoaffinity chromatography. The purified proteins were characterized by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). Rabbit hyperimmune sera were raised against the purified HA and F proteins and assayed by enzyme-linked immunosorbent assay (ELISA), haemagglutination-inhibition (HAI) and virus neutralization (VN) tests. The immunized animals were challenged with a virulent lapinized (rabbit-adapted) strain of RPV. Both HA and F proteins of PPRV protected rabbits against a lethal challenge with lapinized RPV. As expected, RPV HA and F proteins also conferred a similar protection against the homologous challenge. The postchallenge antibody responses were of a true anamnestic type.
Key words: peste-des-petits-ruminants; rinderpest; vaccine; viruses;
Acta virologica 42: 299 - 306, 1998
S. HONDA, T. TAKASAKI, K. OKUNO, M. YASUTOMI, I. KURANE
1st Department of Surgery and
Department of Microbiology, Kinki University School of Medicine, Osaka-sayama, Japan
Summary. - We developed a simple method for establishing Epstein-Barr virus (EBV)-specific, human CD4+ T cell clones. The method originates from our experience that the regression of cell growth in in vitro EBV transformation of B cells occurs when round lymphoid cells appear in the culture. Peripheral blood mononuclear cells (PBMCs) were cultured with EBV, and IL-2 (20 U/ml) was added to the culture on day 17 after the virus addition. The phenotype of the growing cells was CD3+, CD4+, and CD8-. The cells were cytotoxic for autologous lymphoblastoid B cell line (LCL) and EBV-superinfected autologous LCL. The cytotoxic T lymphocytes (CTLs) were confirmed to be CD4+ T cells but not CD8+ T cells in the culture. CTL clones were established by a limiting dilution method. All the CTL clones had the phenotype of CD3+, CD4+ and CD8-, and proliferated in response to autologous LCL. They produced interferon (IFN)-gamma, interleukin 2 (IL-2) and tumour necrosis factor (TNF)-beta but not IL-4. All but one clone responded to both autologous, EBV-superinfected and non-superinfected LCLs. Proliferative and cytotoxic responses to allogenic LCLs were heterogeneous. These results suggest that this method induces heterogeneous, EBV-specific CD4+ CTL clones and is useful for analysis of CD4+ T cells in EBV infections.
Key words: Epstein-Barr virus; CD4+ T lymphocyte; cytotoxic T
lymphocyte clone; limiting dilution method
Acta virologica 42: 307 - 313, 1998
K. KANDA, Y. KITAJIMA, Y. MORIYAMA, F. KATO, A. MURATA
Institute of Applied Microbiology, Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan
Summary. - A region homologous to the genome of plasmid integrative phage J7W-1 was detected in the largest plasmid in 3 out of 22 type strains of Bacillus thuringiensis, dendrolimus (DEN), aizawai (AIZ) and indiana (IND). Phage induction by ethidium bromide observed particularly in the J7W-1 lysogen was identified in DEN and IND but not AIZ strains. The morphology of the phage induced in DEN and IND strains was identical to J7W-1, but the phage production in IND strain was lower as compared to the J7W-1 lysogen. Although the restriction analysis indicated that the prophage in DEN strain possessed a complete J7W-1 genome, modification and/or deletion had presumably occurred in AIZ and IND strains.
Key words: bacillus thuringiensis; plasmid integrative phage;
prophage distribution; ethidium bromide induction
Acta virologica 42: 315 - 318, 1998
M. BYSTRICKÁ, L. SOLÁRIKOVÁ, Ľ. GAŠPARÍKOVÁ, D. STANEKOVÁ, M. MOKRÁŠ, E. KOVÁČOVÁ, A. SABÓ, G. RUSS
Institute of Virology, Slovak Academy of Sciences, Dúbravská cesta 9, 842 46 Bratislava, Slovak Republic; National Reference Centre for Prevention of HIV/AIDS, Institute of Preventive and Clinical Medicine, Bratislava; Department of AIDS, Clinic of Infectious Diseases, Bratislava
Summary. - Thirty sera of human immunodeficiency virus-positive (HIV+) and 37 sera of HIV-negative (HIV-) individuals in Slovakia were tested for the presence of antibodies to herpes simplex virus type 2 (HSV-2) glycoprotein G (gG). A notable difference between the prevalence of HSV-2-specific antibodies in HIV+ and that in HIV- individuals was found (37% vs. 11%) confirming and extending previous reports that HSV-2 infection is an important risk factor for HIV transmission. Efforts toward the detection of HSV-2 infection and its therapy by anti-HSV drugs should be considered an important factor in decreasing the risk of contracting and spreading of HIV in Slovakia.
Key words: herpes simplex virus type 2; human immunodeficiency
virus; glycoprotein G-2; immunoblot analysis; ELISA; antibodies; human
Acta virologica 42: 319 - 324, 1998
J. FRÁNOVÁ-HONETŠLEGROVÁ, M. ERBENOVÁ, R.R. MARTIN
Department of Plant Virology, Institute of Plant Molecular Biology,
Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 České
Budějovice, Czech Republic;
Research and Breeding Institute of Pomology Holovousy, Holovousy, Czech Republic;
USDA-ARS-HCRL, Corvallis, OR, USA
Summary. - Leaves of symptomless Fragaria ananassa Duch cv. Čačanská raná were grafted onto Fragaria vesca indicator clones. Thirty-five of 72 grafted indicator plants developed leaf mottle symptoms. Isometric virus-like particles were observed in purified preparations from symptomatic leaves of F. vesca. The latter were mechanically inoculated to herbaceous host plants. A virus was successfully purified from Nicotiana occidentalis 37 B symptomatic plants by differential and sucrose density gradient centrifugations and a polyclonal antiserum to the virus was prepared. On the basis of serological reactions, symptomatology on herbaceous hosts and electron microscopy studies the virus was identified as tobacco necrosis virus (TNV) D-strain. This is the first isolation of TNV from strawberry leaves and its first finding on strawberry in the Czech Republic. The new experimental hosts N. aucalis, N. bentamiana, N. occidentalis 37 B (systemic hosts), and Ammobium alatum, N. bigelovi, Petunia hybrida (local hosts) for TNV are reported. These results may not exclude the presence of strawberry mottle virus as a causal agent of mottle symptoms in the tested plant samples. Further research is necessary to clarify the aetiology of the strawberry mottle.
Key words: tobacco necrosis virus; fragaria; virus isolation;
electron microscopy; enzyme-linked immunosorbent assay; strawberry mottle
Acta virologica 42: 325 - 331, 1998
Federal Research Centre for Virus Diseases of Animals, Friedrich-Loeffler-Institute, Boddenblick 5a, 17498 Insel Riems, Germany
Summary. - A reverse transcription-polymerase chain reaction (RT-PCR) assay using four different primer pairs for the detection of equine arteritis virus (EAV) RNA in semen and tissue samples was evaluated. A fragment encoding the leader sequence of the EAV genome was most successfully amplified. The specificity and sensitivity of RT-PCR was assessed by virus isolation in cell culture, restriction analysis, dot blot hybridisation and nested PCR. To this end, 23 semen samples from seropositive stallions and 11 tissue samples from 4 aborted foals were tested. Compared to the virus isolation test in cell culture, the sensitivity of the molecular methods proved to be higher. In the RT-PCR, dot blot hybridisation and nested PCR tests, semen samples from 11 stallions and tissue samples from all 4 foals were found positive, while the virus could be isolated in cell culture from only 4 semen samples and tissue samples from 1 aborted foal. The sensitivity of the dot blot hybridisation test was superior to that of the RT-PCR test. The nested PCR test proved to be the most sensitive one, because 3 semen samples were recognised as positive by this method only. Considering the sensitivity, and rapidity and reliability, RT-PCR followed by dot blot hybridisation or nested PCR represents the best method for diagnosis of EAV and should be included in the official diagnostic regimes.
Key words: equine arteritis virus; RT-PCR; dot blot hybridisation;
nested PCR; semen samples; diagnostics
Acta virologica 42: 333 - 339, 1998
T. MORAVEC, N. ČEŘOVSKÁ, A. PAVLÍČEK
Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Na Karlovce 1a, 160 00 Prague 6, Czech Republic
Summary. - Six monoclonal antibodies (MoAbs) against potato virus A (PVA) were prepared and used in enzyme-linked immunosorbent assay (ELISA), immunoblot analysis and electron microscopic study of the virus. Four MoAbs, 151, 290, 328 and 634, reacted with purified virus preparation in dot blot test and showed strong reaction also with virus coat protein (CP) denatured by sodium dodecyl sulphate (SDS), while two MoAbs, 534 and 187, gave significantly weaker reaction with denatured CP than with purified virus. On electron micrographs, MoAb 534 effected binding only on few separate locations of the virus surface after prolonged storage. We presume that this MoAb recognized a conformation-dependent epitope.
Key words: potato virus A; monoclonal antibodies; immunoblot
analysis; electron microscopy
Acta virologica 42: 341 - 346, 1998
J. MERTELÍK, V. MOKRÁ
Research Institute of Ornamental Gardening, 252 43 Průhonice, Czech Republic
Summary. - The occurrence of tomato spotted wilt virus (TSWV) in horticulture crops and weeds in the Czech Republic has been studied in 1992-1997. During this period TSWV was established in 91 plant species. Virus identity was based on the host range, serology and electron microscopy. Natural TSWV infection was detected in glasshouses where the main vector Frankliniella occidentalis was present too. The most frequently TSWV-infected plant species were Chrysanthemum morifolium and Zantedeschia sp. Among vegetable crops, the TSWV infection was very frequently detected in tomatoes and peppers. In all cases these plants were nursed or grown in glasshouses together with different species of ornamental plants, many of which were TSWV-infected. Among weeds, the TSWV infection occurred very often in Stellaria media and Galinsoga parviflora. These two plant species were prevalent in glasshouses and were also good hosts of F. occidentalis.
Key words: tomato spotted wilt virus; Bunyaviridae; Tospovirus;
Czech Republic; ornamental plants; vegetables; weeds
Acta virologica 42: 347 - 351, 1998
WERE HANTAVIRUSES EVENTUALLY RESPONSIBLE FOR THE LOST ANASAZI CULTURE?
Laboratoire de Virologie, Faculté de Médicine, F 29285 Brest Cédex,
Acta virologica 42: 353, 1998
PREPARATION OF MONOCLONAL ANTIBODIES TO N PROTEIN OF RINDERPEST VIRUS AND THEIR USE IN VIRAL ANTIGEN DETECTION
M.C. JOSEPH, G. BUTCHAIAH, M. MEENAKSHI, R.K. SINGH
National Biotechnology Centre, Indian Veterinary Research Institute, Izatnagar 243 122, UP, India
Key words: rinderpest virus; monoclonal antibodies; N protein;
Acta virologica 42: 355 - 356, 1998