Arenoviruses in Vero cells: ultrastructural studies

Area of Science:

• Virology
• Cell Biology
• Microscopy

Background:

• The arenovirus group is a newly constituted viral family.
• Morphological characterization is crucial for viral classification.

Purpose of the Study:

• To perform thin-section electron microscopy on Vero cell cultures infected with arenaviruses.
• To compare the morphology of various arenaviruses with the prototype lymphocytic choriomeningitis virus.

Main Methods:

• Thin-section electron microscopy of infected Vero green monkey kidney cell cultures.
• Negative-contrast electron microscopy of virus particles from supernatant fluids.

Main Results:

• Junin, Machupo, Amapari, Pichinde, Parana, Tamiami, and Latino viruses were morphologically indistinguishable from lymphocytic choriomeningitis virus.
• Virus particles were pleomorphic, 60-280 nm, budding from plasma membranes, and contained dense granules.
• Negative-contrast microscopy showed pleomorphic, membrane-bound forms with surface projections (90-350 nm).

Conclusions:

• The morphological similarities support the current classification of a distinct arenovirus group.
• Electron microscopy is effective in characterizing arenavirus morphology and aiding in group delineation.