JC Papovavirus in Progressive Multifocal Leukoencephalopathy

Abstract

Brain tissue from seven patients with progressive multifocal leukoencephalopathy was tested for the presence of papovaviruses. IC virus, a human papovavirus, was identified in all seven cases. Virus was isolated in tissue culture from extracts from each of four patients and was detected by immunofluorescence in sections from the other three. The new isolates were indistinguishable from the prototypical IC strain serologically and in all biological characteristics examined. Thus IC virus has, to date, been associated with 20 cases of progressive multifocal leukoencephalopathy.