Methods to Study Monocyte Migration Induced by HIV-Infected Cells

Freeze-fracture, freeze-etch complementary pairs of virus-infected cells reveal value of etching even when relatively high concentrations of cryoprotectants are used

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081541 ◽

1978 ◽

Vol 36 (2) ◽

pp. 136-137

Author(s):

Russell L. Steere ◽

Eric F. Erbe

Keyword(s):

Plant Tissue ◽

Phosphate Buffer ◽

Infected Plant ◽

Freeze Fracture ◽

Distilled Water ◽

Virus Infected Plant ◽

Infected Cells ◽

High Concentrations

It has been assumed by many involved in freeze-etch or freeze-fracture studies that it would be useless to etch specimens which were cryoprotected by more than 15% glycerol. We presumed that the amount of cryoprotective material exposed at the surface would serve as a contaminating layer and prevent the visualization of fine details. Recent unexpected freeze-etch results indicated that it would be useful to compare complementary replicas in which one-half of the frozen-fractured specimen would be shadowed and replicated immediately after fracturing whereas the complement would be etched at -98°C for 1 to 10 minutes before being shadowed and replicated.Standard complementary replica holders (Steere, 1973) with hinges removed were used for this study. Specimens consisting of unfixed virus-infected plant tissue infiltrated with 0.05 M phosphate buffer or distilled water were used without cryoprotectant. Some were permitted to settle through gradients to the desired concentrations of different cryoprotectants.

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Further Observations on the Virus of Epizootic Diarrhea of Infant Mice. An Electron Microscopic Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060568 ◽

1967 ◽

Vol 25 ◽

pp. 110-111

Author(s):

W. G. Banfield ◽

G. Kasnic ◽

J. H. Blackwell

Keyword(s):

Electron Microscope ◽

Infected Cell ◽

Microscopic Study ◽

Intestinal Epithelium ◽

Ultrastructural Study ◽

Osmium Tetroxide ◽

Lead Citrate ◽

Electron Microscopic ◽

Virus Particles ◽

Infected Cells

An ultrastructural study of the intestinal epithelium of mice infected with the agent of epizootic diarrhea of infant mice (EDIM virus) was first performed by Adams and Kraft. We have extended their observations and have found developmental forms of the virus and associated structures not reported by them.Three-day-old NLM strain mice were infected with EDIM virus and killed 48 to 168 hours later. Specimens of bowel were fixed in glutaraldehyde, post fixed in osmium tetroxide and embedded in epon. Sections were stained with uranyl magnesium acetate followed by lead citrate and examined in an updated RCA EMU-3F electron microscope.The cells containing virus particles (infected) are at the tips of the villi and occur throughout the intestine from duodenum through colon. All developmental forms of the virus are present from 48 to 168 hours after infection. Figure 1 is of cells without virus particles and figure 2 is of an infected cell. The nucleus and cytoplasm of the infected cells appear clearer than the cells without virus particles.

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Electron Microscopy of a Herpesvirus Isolated from Marek's Disease in Duck and Chicken Embryo Fibroblast Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100858 ◽

1968 ◽

Vol 26 ◽

pp. 222-223 ◽

Cited By ~ 1

Author(s):

Keyvan Nazerian

Keyword(s):

Inclusion Bodies ◽

Chicken Embryo Fibroblast ◽

Marek's Disease ◽

Marek’S Disease ◽

Duck Embryo Fibroblast ◽

Multinucleated Cells ◽

Viral Particles ◽

Infected Cells ◽

And Control ◽

Do So

A herpes-like virus has been isolated from duck embryo fibroblast (DEF) cultures inoculated with blood from Marek's disease (MD) infected birds. Cultures which contained this virus produced MD in susceptible chickens while virus negative cultures and control cultures failed to do so. This and other circumstantial evidence including similarities in properties of the virus and the MD agent implicate this virus in the etiology of MD.Histochemical studies demonstrated the presence of DNA-staining intranuclear inclusion bodies in polykarocytes in infected cultures. Distinct nucleo-plasmic aggregates were also seen in sections of similar multinucleated cells examined with the electron microscope. These aggregates are probably the same as the inclusion bodies seen with the light microscope. Naked viral particles were observed in the nucleus of infected cells within or on the edges of the nucleoplasmic aggregates. These particles measured 95-100mμ, in diameter and rarely escaped into the cytoplasm or nuclear vesicles by budding through the nuclear membrane (Fig. 1). The enveloped particles (Fig. 2) formed in this manner measured 150-170mμ in diameter and always had a densely stained nucleoid. The virus in supernatant fluids consisted of naked capsids with 162 hollow, cylindrical capsomeres (Fig. 3). Enveloped particles were not seen in such preparations.

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Studies of a Defective Measles Virus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100780 ◽

1968 ◽

Vol 26 ◽

pp. 208-209

Author(s):

R. M. McCombs ◽

M. Benyesh-Melnick ◽

J. P. Brunschwig

Keyword(s):

Inclusion Bodies ◽

Measles Virus ◽

Giant Cells ◽

Helical Structures ◽

Thin Sections ◽

Virus Particles ◽

Extracellular Virus ◽

Culture Cells ◽

Infected Cells ◽

Eosinophilic Inclusions

Measles virus is an agent that is capable of replicating in a number of different culture cells and generally causes the formation of multinucleated giant cells. As a result of infection, virus is released from the cells into the culture fluids and reinfection can be initiated by this cell-free virus. The extracellular virus has been examined by negative staining with phosphotungstic acid and has been shown to be a rather pleomorphic particle with a diameter of about 140 mμ. However, no such virus particles have been detected in thin sections of the infected cells. Rather, the only virus-induced structures present in the giant cells are eosinophilic inclusions (intracytoplasmic or intranuclear). These inclusion bodies have been shown to contain helical structures, resembling the nucleocapsid observed in negatively stained preparations.

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Studies of Epstein-Barr Virus Antigens Using Immunoperoxidase and Immunofluorescence Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011533x ◽

1975 ◽

Vol 33 ◽

pp. 342-343

Author(s):

R. Stephens ◽

K. Traul ◽

D. Woolf ◽

P. Gaudreau

Keyword(s):

Electron Microscopy ◽

Nasopharyngeal Carcinoma ◽

Epstein Barr Virus ◽

Barr Virus ◽

If Technique ◽

Infected Cells ◽

Virus Antigens ◽

Epstein Barr ◽

Virus Capsid Antigen ◽

Antigen Reactivity

A number of antigens have been found associated with persistent EBV infections of lymphoblastoid cells. Identification and localization of these antigens were principally by immunofluorescence (IF) techniques using sera from patients with nasopharyngeal carcinoma (NPC), Burkitt lymphoma (BL), and infectious mononucleosis (IM). Our study was mainly with three of the EBV related antigens, a) virus capsid antigen (VCA), b) membrane antigen (MA), and c) early antigens (EA) using immunoperoxidase (IP) techniques with electron microscopy (EM) to elucidate the sites of reactivity with EBV and EBV infected cells.Prior to labeling with horseradish peroxidase (HRP), sera from NPC, IM, and BL cases were characterized for various reactivities by the indirect IF technique. Modifications of the direct IP procedure described by Shabo and the indirect IP procedure of Leduc were made to enhance penetration of the cells and preservation of antigen reactivity.

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Lectin Binding Studies on RNA Tumor Virus-Infected Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115250 ◽

1975 ◽

Vol 33 ◽

pp. 326-327

Author(s):

D. C. Hixson

Keyword(s):

Binding Sites ◽

Lectin Binding ◽

Culture Conditions ◽

3T3 Cells ◽

Binding Studies ◽

Con A ◽

Microscopic Studies ◽

Tumor Virus ◽

Infected Cells ◽

Cell Culture Conditions

The abilities of plant lectins to preferentially agglutinate malignant cells and to bind to specific monosaccharide or oligosaccharide sequences of glycoproteins and glycolipids make them a new and important biochemical probe for investigating alterations in plasma membrane structure which may result from malignant transformation. Electron and light microscopic studies have demonstrated clustered binding sites on surfaces of SV40-infected or tryp- sinized 3T3 cells when labeled with concanavalin A (con A). No clustering of con A binding sites was observed in normal 3T3 cells. It has been proposed that topological rearrangement of lectin binding sites into clusters enables con A to agglutinate SV40-infected or trypsinized 3T3 cells (1). However, observations by other investigators have not been consistent with this proposal (2) perhaps due to differences in reagents used, cell culture conditions, or labeling techniques. The present work was undertaken to study the lectin binding properties of normal and RNA tumor virus-infected cells and their associated viruses using lectins and ferritin-conjugated lectins of five different specificities.

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Assembly of VP26 in herpes simplex virus-1 capsid implicated by 3-D structure of recombinant capsid

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140579 ◽

1995 ◽

Vol 53 ◽

pp. 840-841

Author(s):

Z. Hong Zhou ◽

Jing He ◽

Joanita Jakana ◽

J. D. Tatman ◽

Frazer J. Rixon ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

3D Structure ◽

Structure Study ◽

Herpes Simplex Virus 1 ◽

Shell Proteins ◽

Life Threatening ◽

Infected Cells ◽

Simplex Virus ◽

Hsv 1

Herpes simplex virus-1 (HSV-1) is a ubiquitous virus which is implicated in diseases ranging from self-curing cold sores to life-threatening infections. The 2500 Å diameter herpes virion is composed of a glycoprotein spike containing, lipid envelope, enclosing a protein layer (the tegument) in which is embedded the capsid (which contains the dsDNA genome). The B-, and A- and C-capsids, representing different morphogenetic stages in HSV-1 infected cells, are composed of 7, and 5 structural proteins respectively. The three capsid types are organized in similar T=16 icosahedral shells with 12 pentons, 150 hexons, and 320 connecting triplexes. Our previous 3D structure study at 26 Å revealed domain features of all these structural components and suggested probable locations for the outer shell proteins, VP5, VP26, VP19c and VP23. VP5 makes up most of both pentons and hexons. VP26 appeared to bind to the VP5 subunit in hexon but not to that in penton.

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Umatilla Virus Association with Fibrils and Tubules in Cultured Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002063 ◽

1980 ◽

Vol 38 ◽

pp. 476-477

Author(s):

Neil M. Foster ◽

Ruth D. Breckon

Keyword(s):

Bluetongue Virus ◽

Linear Array ◽

Cultured Cells ◽

Intimate Association ◽

Infected Cells ◽

Dark Staining ◽

In Cells

Macrotubules have been described1 in cells infected with Umatilla virus (UMAV), an orbivirus for which bluetongue virus (BTV) is the protype. Macrotubules, often in linear array, were observed in the cytoplasm and in intimate association with viroplasms of infected cells. Macrotubules had outside and inside diameters of 20 and 15 nm and many had dark-staining centers with diameters similar to the interiors of the tubules. UMAV was 60 nm and the RNA core was 30 nm in diameter. This report describes the association of UMAV with macrotubules and two types of microtubules.

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