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Isolation of Brain-infiltrating Leukocytes
06:44

Isolation of Brain-infiltrating Leukocytes

Published on: June 13, 2011

POLYOMA-LIKE VIRIONS IN HUMAN DEMYELINATING BRAIN DISEASE

A F HOWATSON, M NAGAI, G M ZURHEIN

    Canadian Medical Association Journal
    |August 28, 1965
    PubMed

    Insights

    Electron microscopy revealed papova-like virus particles in brain tissue from progressive multifocal leukoencephalopathy (PML) patients. These particles structurally resemble polyoma-SV40-K virions, necessitating further investigation with fresh tissue.

    Area of Science:

    • Neuropathology
    • Virology
    • Electron Microscopy

    Background:

    • Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system.
    • Previous studies have suggested a viral etiology for PML.

    Purpose of the Study:

    • To examine brain tissue from PML patients using electron microscopy.
    • To characterize the morphology of viral particles observed in PML.

    Main Methods:

    • Autopsy brain tissue specimens from three PML patients were analyzed.
    • Electron microscopy was employed for ultrastructural examination.
    • Negative staining technique was used to define particle morphology.

    Main Results:

    • Particles resembling the papova virus group were identified in all three PML cases.
    • Negative staining revealed these particles are structurally similar to polyoma-SV40-K virions.

    Conclusions:

    • The findings confirm the presence of papova-like virus particles in PML.
    • The observed virions share structural similarities with polyoma-SV40-K.
    • Further research using fresh, unfixed PML tissue is crucial for investigating the biological properties of these particles.
    Keywords:
    CEREBRAL SCLEROSIS, DIFFUSEDEMYELINATIONMICROBIOLOGYMICROSCOPY, ELECTRONPATHOLOGYPOLYOMA VIRUSSTAINS AND STAINING

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