Search PubMed⌕ Search

Biomedical subjects

F Uno

Publications and source records attributed to F Uno.

At least 19 recordsLinked to original sources
PubMed1998

[Structure and assembly of human beta herpesviruses].

This review is concerned with the structure and assembly of HCMV, HHV6 and HHV7. A characteristic ultrastructural feature common to all these viruses is a distinct tegumentary coating of intracytoplasmic capsids. The tegument structure is also distinctly seen in the virions of HHV6 and HHV7. Morphologically, acquisition of the tegument was observed to have taken place in the cytoplasm. Immunoelectron microscopic studies of HCMV infected cells, however, have demonstrated the existence of a tegument protein, pp150, on the surface of intranuclear capsids as well as on capsids in the cytoplasm and in extracellular virions. In addition, another tegument protein, pp65 has been detected within the matrix of cytoplasmic and extracellular dense bodies but not in virions. The molecular mechanism of the assembly of beta herpesviruses was also discussed.

Capsid↗
PubMed1997

High-resolution immuno-scanning electron microscopy using a non-coating method: study of herpes simplex virus glycoproteins on the surface of virus particles and infected cells.

The expression of two glycoproteins, i.e. glycoprotein C (gC) and glycoprotein D (gD), of herpes simplex virus type 1 (HSV-1) on the surface of extracellular particles of this virus was examined by immuno-scanning electron microscopy. Scanning electron microscopy specimens of infected cells immuno-labelled against the glycoproteins with colloidal gold particles were prepared by a conventional coating and a non-coating method. Surface ultrastructure of infected cells and gold particles were observed more clearly with specimens prepared by the non-coating method. The appearance of virus particles in association with glycoprotein expression on these particles and on the surface of infected cells was then studied. Progeny virus particles began to appear 6 h after infection, increased in number as the infection proceeded, and covered most of the cell surface by 16 h. Six to 24 h after the infection, the labelling density for each glycoprotein on virus particles remained constant. The labelling density for gD was always higher than that for gC. The patch-like distribution of gold-labelling against gD was often detected on infected cell monolayers at the exponential and late stage of one cycle of virus growth. The labelling density for gD on virus particles was the highest on these produced in Vero and L-929 cells, moderate in MRC-5, BHK-21 and FL cells, and the lowest in HEp-2 cells.

Animals↗
PubMed1997

In vitro selection of variants of herpes simplex virus type 1 which differ in cytopathic changes.

To analyze the mechanisms for in vitro emergence of the syncytial variants of herpes simplex virus type 1 (HSV-1), several cell lines were infected with a mixture of equal amounts of two HSV-1 variants, one syncytial and the other non-syncytial, and changes in their relative abundance were monitored during passage. With a combination of two variants of the Miyama strain of HSV-1, the syncytial variant became dominant during passage in Vero, RK-13 and FL cells. On the other hand, the ratios of the two variants remained around 1:1 during the passage in HEp-2, MGC and HEL cells. In another set of variants of the SKO strain of HSV-1, the outcomes were different from those of the Miyama strain in the FL, MGC and HEp-2 cells. The ratios of the two variants remained around 1:1 during passage in FL cells, while the non-syncytial variant became dominant during passage in MGC and HEp-2 cells. In addition, we examined the effects of a complement and interferon-beta (IFN-beta) on the outcome of the selection. As a result, the complement slowed the selection of a syncytial variant, whereas IFN-beta facilitated it.

Cell Line↗
PubMed1997

Infection of a human retinal pigment epithelial cell line with human herpesvirus 6 variant A.

A retinal pigment epithelial (RPE) cell line (K-1034) was examined for its susceptibility to human herpesvirus 6 variant A (HHV-6A). Exposure of K-1034 cells to HHV-6A induced the formation of multinucleated giant cells, which was suppressed by an inhibitor of viral DNA synthesis. In the giant cells, herpesvirus nucleocapsids were demonstrated by electron microscopy and the viral glycoprotein B was detected by immunofluorescence assay. These results indicate that K-1034 cells are susceptible to HHV-6A and suggest that HHV-6A has an ability to directly destroy epithelial cells.

Cells, Cultured↗
PubMed1996

Electron microscopic observations of aberrant capsids of pseudorabies virus.

Interactions between four strains of pseudorabies virus (PrV) and seven kinds of cell lines were examined. Three kinds of cells (SKL, CPK and PK-15) were especially infected with PrV at an MOI of about 10 PFC/cell. At sequential intervals after infection, cells of these types were collected for electron microscopic observations and the infectious doses of culture fluids were assayed. Developmental features of PrV were found to be very similar to those of herpes simplex virus (HSV), with the slight difference that PrV developed a little earlier and more vigorously than did HSV. At the late stage of infection, aberrant capsids of PrV were observed frequently in the nucleus of SKL but rarely in the nuclei of CPK and PK-15. The titer of infectious virus produced by SKL was much larger than that produced by CPK and PK-15. Immuno-electron microscopic examination using a monoclonal antibody against the major capsid protein of PrV clearly demonstrated that the complete and aberrant capsids have a common epitope. The mechanism of the formation of aberrant capsids is discussed.

Animals↗
PubMed1995

Ultrahigh-resolution scanning electron microscopy of MDCK cells infected with influenza viruses.

Ultrahigh-resolution scanning electron microscopy of MDCK cells infected with influenza viruses was carried out by the uncoated uranyl acetate staining preparation method. Ridge-like protrusions were detected on virus particles and were considered to be an indication of aggregated glycoprotein spikes. Bundles of filamentous virus particles along with bacillary virus particles were encountered on MDCK cells infected with freshly isolated strains of type A virus. Filamentous virus particles that were twisted like ropes were observed on MDCK cells infected with strains of type B virus.

Cell Membrane↗
PubMed1993

Characterization of 17 human immunodeficiency virus-1 carrier cell lines with T cell, myelomonocyte, or megakaryocyte lineages.

Of 29 hematopoietic cell lines tested for susceptibility to human immunodeficiency virus (HIV)-1HTLV-IIIB infection, all CD4+ cell lines became infected. Continuous culturing of infected cell lines resulted in nine HIV-1 carrier cell lines, including, for the first time, an HIV-1 carrier megakaryoblastic cell line, MEG-01/HIV. The immunophenotypic profiles of a total of 17 HIV-1 carrier cell lines (nine newly and eight previously established cell lines) were compared with their respective parental noninfected cell lines. Except for total absence of CD4 expression, the expression of other antigens was variable among the 17 HIV-1 carrier cell lines. Persistent and consistent replication of infectious HIV-1 was detected in all of them in varying quantities. The great variability observed in both the altered marker expression, with respect to that of the noninfected parental cell lines, and in the quantities of persistently produced infectious HIV-1 was, nevertheless, specific to the individual cell lines. Furthermore, the present study demonstrates that there is no apparent correlation in the quantity of HIV-1 produced to either T cell, myelomonocytic cell, or megakaryocytic cell types. Instead, the results suggest that a particular interaction between HIV-1 and individual clonal cell lines may provide insight into the extremely complex immune dysregulation associated with the pathogenesis of acquired immune deficiency syndrome. Thus, the 17 HIV-1 carrier cell lines of diverse origin presented here provide valuable and unique models for further understanding acquired immune deficiency syndrome pathogenesis at the cellular and molecular levels.

Adolescent↗
PubMed1992

Detection of herpes simplex and varicella-zoster virus DNA by field-inversion gel electrophoresis from clinical materials.

A simple method using field-inversion gel electrophoresis (FIGE) was applied to detect herpes simplex virus (HSV) and varicella-zoster virus (VZV) genomes in clinical specimens. The whole genomes of these viruses could be detected in small vesicle tissues by the FIGE method regardless of their clinical stages of skin lesions. And the sensitivity of the FIGE method was equivalent to that of an immunofluorescent (IF) method. These data indicated usefulness of the FIGE method to detect the whole genomes of HSV and VZV in clinical specimens.

DNA, Viral↗
PubMed1992

Ultra-high-resolution scanning electron microscopy of vaccinia virus and its recombinant carrying the gag gene of human immunodeficiency virus type 1.

FL cells infected with vaccinia virus or its recombinant carrying the gag gene of human immunodeficiency virus type 1 (HIV-1) were examined by ultra-high-resolution scanning electron microscopy. Virions, whether located extracellularly or intracellularly, had a brick-shaped or watermelon appearance as a whole. Extracellular virions observed on the surface of infected cells had variable surface ultrastructures depending on the manner in which particular virions were wrapped in cell membranes. Most of the intracellular naked virions adherent to the inner face of cell surface membranes clearly exhibited ridgy, rod-shaped or globular surface structures on their surface. HIV-like particles with a diameter of about 100 nm and virions of vaccinia virus were both observed distinctly on the surface of FL cells infected with the recombinant virus.

Amnion↗
PubMed1991

Neurovirulent strains of herpes simplex virus type 1 are not necessarily competent for reactivatable latency.

Ability of two neurovirulent strains (F and +GC (LPV) Miyama) of herpes simplex virus type 1 (HSV-1) to establish and maintain reactivatable latency in trigeminal ganglia (TG) was compared after intranasal inoculation of mice. The +GC (LPV) Miyama strain showed a very low rate of virus reactivation in explant cultures of TG, while the F strain showed a high rate of reactivation. These data indicate that neurovirulent strains of HSV-1 are not always competent for reactivatable latency, although most virulent strains of HSV-1 thus far reported were competent for reactivatable latency.

Administration, Intranasal↗
PubMed1991

Reactivatable latency of three avirulent strains of herpes simplex virus type 1 after intranasal inoculation in mice.

In order to elucidate the mechanism of latent infection of herpes simplex virus (HSV), reactivatable latency of three avirulent strains (SKO-1B, -GCr Miyama, SKa) of HSV type 1 was comparatively examined in a mouse latency model. The SKO-1B strain showed high rate of virus reactivation from explanted trigeminal ganglia without n-butyrate enhancement, while the other two strains showed a very low rate of virus reactivation in the absence of n-butyrate. In the presence of n-butyrate, however, the rate of the -GCr Miyama strain jumped to a comparable level with that of SKO-1B, although the rate of SKa remained at a low level. A more precise follow-up experiment changing the virus dose highlighted the difference of the ability to reactivate from the latent state between SKO-1B and -GCr Miyama. Virus titer in trigeminal ganglia during acute phase, infectivity to cell lines of neural origin, and susceptibility to acyclovir and phosphonoacetate were assayed to know the reasons for the variation in the ability of reactivatable latency among these strains. It was concluded that the reduced infectivity to neural cells, and limited ability of reactivatable latency shown by the SKa strain could mainly be attributed to the deficiency of thymidine kinase activity.

Acyclovir↗
PubMed1990

Detection of varicella-zoster virus DNA by field-inversion gel electrophoresis.

A new method for detection of varicella-zoster virus (VZV) DNA using field-inversion gel electrophoresis (FIGE) was devised. VZV-genomic DNA could be differentiated from the host cell DNA of human embryonic lung (HEL) fibroblasts infected with VZV under electrophoretic conditions allowing resolution of linear and double-stranded DNAs in the 49-230 kilobase pairs (Kb) range. The detection of VZV-genomic DNA from infected HEL cells was successful regardless of whether the VZV was a laboratory strain, live vaccine strain, or fresh isolate. Under the same electrophoretic conditions, DNA of VZV-infected HEL cells could be clearly differentiated from DNA obtained from HEL cells infected with herpes simplex virus type 1 (HSV-1), type 2 (HSV-2), or human cytomegalovirus (HCMV). Furthermore, VZV genomic DNA could be detected from as small a sample as 1.9 x 10(4) VZV-infected HEL cells. Finally, we could detect VZV genomic DNA from 10 samples of vesicle tissue (blister lids, each about 1-4 mm2) and one sample of vesicle fluid (about 5 microliters) obtained from patients diagnosed as having herpes-zoster. The results of this study indicate that FIGE is a simple and promising method for the detection of VZV from clinical materials as well as infected in vitro cultured cells.

Blotting, Southern↗
PubMed1989

Electron microscopic study of a herpes-type virus isolated from an infant with exanthem subitum.

Human lymphocytes and MT4 cells infected with a virus isolated from a patient with exanthem subitum were examined by transmission and scanning electron microscopy. The most striking characteristic of the ultrastructure of this herpes-type virus was that nucleocapsids located outside the nucleus were each coated distinctly with a tegument of moderate electron density. Tubular structures formed due to some mistakes in the viral assembly were also detected in the nucleus. Morphological differentiation of this virus from the other human herpesvirus was discussed. From these observations it was concluded that this virus has the same ultrastructural characteristics as HBLV (HHV-6).

Capsid↗
PubMed1988

Effect of recombinant mouse interferon-beta on acute and latent herpes simplex infection in mice.

The antiviral effect of recombinant mouse interferon-beta (rMuIFN-beta) on herpes simplex virus type 1 (HSV-1) in experimentally infected mice was examined at several stages of infection as a model for the treatment of human HSV infection. Recombinant MuIFN-beta protected mice from lethal intraperitoneal challenge with virulent HSV-1 strains. The in vitro reactivation of HSV from latently infected trigeminal ganglia was also suppressed by treatment with rMuIFN-beta. Thus, rMuIFN-beta was effective against HSV-1 during acute infection and during in vitro reactivation of latent HSV. However, rMuIFN-beta was not effective in preventing the establishment of latent infection, or in eliminating a previously established latent infection.

Acute Disease↗
PubMed1986

In vitro cytopathology and pathogenicity to inbred mice shown by five variants of a laboratory strain of type 1 herpes simplex virus.

The in vitro cytopathology and the neurovirulence to inbred mice demonstrated by five variants originally derived from one laboratory strain (Miyama) of type 1 herpes simplex virus (HSV-1) were studied comparatively. Three of the variants are syncytial [+GC (LPV), +GC (SPV), +GC (81)] and two are non-syncytial [-GCr and -GCf]. The size of plaques produced by the five variants was found to be in the order of +GC (LPV) greater than +GC (81) greater than +GC (SPV) greater than -GCf greater than -GCr. The pathogenicity of these variants was compared in three kinds of inbred mice (AKR, C 3 H/He and C 57 BL) after intraperitoneal (IP) or intracerebral (IC) inoculation. The +GC (LPV) variant was the most virulent as shown by the highest mortality of mice by either route of inoculation. The other four variants caused death of mice only after IC inoculation, and among these variants, +GC (81) was shown to be the most virulent. These data indicate that so far as these five variants of the Miyama strain of HSV-1 are concerned, neurovirulence is positively correlated with their cell fusion activity or the size of plaques which they produce. Pre-IP-inoculation with any of the less virulent variants [-GCr, +GC (SPV) and +GC (81)] protected mice from subsequent lethal infection with +GC (LPV) by the same route of inoculation.

Animals↗
PubMed1986

Mechanism of differences in pathogenicity between two variants of a laboratory strain of herpes simplex virus type 1.

The mechanisms responsible for the difference in neurovirulence to inbred mice between two variants of the Miyama strain of herpes simplex virus type 1 (HSV-1) were studied. After intraperitoneal (i.p.) inoculation, the +GC (LPV) variant reached the spinal cord and the brain, and caused death. Conversely, the -GCr variant lacked the ability to gain access to the central nervous system (CNS) after the same route of infection and failed to kill susceptible mice. The initial virus growth after i.p. inoculation, as indicated by the number of infective centers (ICs) produced by the peritoneal exudate cells (PECs), was compared between these two variants. The virulent +GC (LPV) strain induced much more ICs than the attenuated -GCr variant. When the attenuated variant was preinoculated i.p. 24 hr before the challenge inoculation with the virulent variant by the same route, the production of ICs by the pathogenic variant was highly inhibited, and growth of this variant did not occur in the CNS. Thus, mice were protected from lethal infection by the virulent variant by preinoculation with the attenuated one. Moreover, the ability of mice to resist i.p. infection by HSV-1 was shown to be age-dependent.

Aging↗