Electron Microscopic Observation on the Virus Particle of Japanese B Encephalitis Propagated in PS Cells

An electron microscope study was performed on the ultrastructure and developmental process of the MUKAI strain of Japanese B encephalitis virus propagated in vitro on porcine kidney stable cells. Tne virus particle of Japanese B encephalitis is hexagonal in sections and approximaely 40mμ in the longest diameter, composed of the outer mambran, 20Å thick, viroplasm, 30Å thick and an electron-dense nucleoid, 25mμ in diameter. The virus particles develop by budding process on the wall of the cytoplasmic vacuole. Thereafter, virus particles are densely packed in the vacuole usually in random arrangement and rarely in crystalline arrays. The vacuole containing virus particles gradually moves toward the cell surface and liberates the virus particles to the exterior of the cells through a narrow canaliculus. A structure suggestive of incomplete virus particles was also observed.