Faculty Opinions recommendation of Astrocyte Infection during Rabies Encephalitis Depends on the Virus Strain and Infection Route as Demonstrated by Novel Quantitative 3D Analysis of Cell Tropism.

ABSTRACT Four of six specific pathogen-free cats were infected after intravaginal exposure to molecularly cloned lymphotropic but non-Crandell feline kidney (CRFK)-tropic feline immunodeficiency virus strain TM2 and its AP-1 deletion mutant. The sequences of the env V3-to-V5 region which defines the CRFK tropism were unchanged in the infected cats through the infection. These data suggest that the strain was transmitted across the mucosal epithelium without a broadening of cell tropism.

Download Full-text

Molecular Characterization of Feline Infectious Peritonitis Virus Strain DF-2 and Studies of the Role of ORF3abc in Viral Cell Tropism

Journal of Virology ◽

10.1128/jvi.00189-12 ◽

2012 ◽

Vol 86 (11) ◽

pp. 6258-6267 ◽

Cited By ~ 35

Author(s):

A. Balint ◽

A. Farsang ◽

Z. Zadori ◽

A. Hornyak ◽

L. Dencso ◽

...

Keyword(s):

Molecular Characterization ◽

Virus Strain ◽

Cell Tropism ◽

Feline Infectious Peritonitis Virus ◽

Feline Infectious Peritonitis

Download Full-text

Astrocyte Infection during Rabies Encephalitis Depends on the Virus Strain and Infection Route as Demonstrated by Novel Quantitative 3D Analysis of Cell Tropism

10.20944/preprints202001.0160.v1 ◽

2020 ◽

Author(s):

Madlin Potratz ◽

Luca Zaeck ◽

Michael Christen ◽

Verena teKamp ◽

Antonia Klein ◽

...

Keyword(s):

Target Cells ◽

3D Analysis ◽

Cell Tropism ◽

Tissue Slices ◽

High Preference ◽

Clearing Technique ◽

Inoculation Route ◽

Highly Virulent

Although conventional immunohistochemistry for neurotropic Rabies virus (RABV) usually shows a high preference for neurons, non-neuronal cells are also potential target cells and abortive infection of astrocytes is considered a main trigger of innate immunity in the CNS. While in vitro studies indicated differences between field and less virulent lab-adapted RABVs, a systematic and quantitative comparison of astrocyte tropism in vivo is lacking. Here, a recently developed solvent-based tissue clearing technique was used to measure the RABV cell tropism in infected brains. Immunofluorescence analysis of 1 mm-thick tissue slices enabled 3D segmentation and quantification of infection frequencies of astrocytes and neurons. Comparison of highly virulent street virus clones from fox, dog, and raccoon with three lab strains of intermediate and low virulence revealed remarkable differences in the ability to infect astrocytes in vivo. While all viruses and infection routes led to comparable neuron infection frequencies, striking differences were detected for the infection of astrocytes. Consistent and inoculation route-independent astrocyte infection by field viruses, together with route-dependent or undetectable astrocyte infection by lab-adapted or vaccine viruses strongly suggests a model in which the ability to establish productive astrocyte infection in vivo functionally distinguishes field and attenuated lab RABV strains.

Download Full-text

Astrocyte Infection during Rabies Encephalitis Depends on the Virus Strain and Infection Route as Demonstrated by Novel Quantitative 3D Analysis of Cell Tropism

Cells ◽

10.3390/cells9020412 ◽

2020 ◽

Vol 9 (2) ◽

pp. 412 ◽

Cited By ~ 8

Author(s):

Madlin Potratz ◽

Luca Zaeck ◽

Michael Christen ◽

Verena te Kamp ◽

Antonia Klein ◽

...

Keyword(s):

3D Analysis ◽

Cell Tropism ◽

3D Segmentation ◽

Tissue Slices ◽

High Preference ◽

Field Virus ◽

Inoculation Route ◽

Highly Virulent

Although conventional immunohistochemistry for neurotropic rabies virus (RABV) usually shows high preference for neurons, non-neuronal cells are also potential targets, and abortive astrocyte infection is considered a main trigger of innate immunity in the CNS. While in vitro studies indicated differences between field and less virulent lab-adapted RABVs, a systematic, quantitative comparison of astrocyte tropism in vivo is lacking. Here, solvent-based tissue clearing was used to measure RABV cell tropism in infected brains. Immunofluorescence analysis of 1 mm-thick tissue slices enabled 3D-segmentation and quantification of astrocyte and neuron infection frequencies. Comparison of three highly virulent field virus clones from fox, dog, and raccoon with three lab-adapted strains revealed remarkable differences in the ability to infect astrocytes in vivo. While all viruses and infection routes led to neuron infection frequencies between 7–19%, striking differences appeared for astrocytes. Whereas astrocyte infection by field viruses was detected independent of the inoculation route (8–27%), only one lab-adapted strain infected astrocytes route-dependently [0% after intramuscular (i.m.) and 13% after intracerebral (i.c.) inoculation]. Two lab-adapted vaccine viruses lacked astrocyte infection altogether (0%, i.c. and i.m.). This suggests a model in which the ability to establish productive astrocyte infection in vivo functionally distinguishes field and attenuated lab RABV strains.

Download Full-text

Direct phase determination in electron crystallography: small organic molecules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130468 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1166-1167

Author(s):

Douglas L. Dorset

Keyword(s):

Organic Molecules ◽

Data Sets ◽

Temperature Structure ◽

3D Analysis ◽

Intensity Data ◽

Electron Crystallography ◽

Phase Determination ◽

Measured Intensity ◽

3D Data

The quantitative use of electron diffraction intensity data for the determination of crystal structures represents the pioneering achievement in the electron crystallography of organic molecules, an effort largely begun by B. K. Vainshtein and his co-workers. However, despite numerous representative structure analyses yielding results consistent with X-ray determination, this entire effort was viewed with considerable mistrust by many crystallographers. This was no doubt due to the rather high crystallographic R-factors reported for some structures and, more importantly, the failure to convince many skeptics that the measured intensity data were adequate for ab initio structure determinations.We have recently demonstrated the utility of these data sets for structure analyses by direct phase determination based on the probabilistic estimate of three- and four-phase structure invariant sums. Examples include the structure of diketopiperazine using Vainshtein's 3D data, a similar 3D analysis of the room temperature structure of thiourea, and a zonal determination of the urea structure, the latter also based on data collected by the Moscow group.

Download Full-text