CENTROSOME INJURY IN CELLS INFECTED WITH HUMAN CYTOMEGALOVIRUS

The organization of the mitotic apparatus was studied in human embryo lung fibroblasts (HEL) and Vero cells at 4 days postinfection with hum an cytomegalovirus (HCMV) strain AD 169. The bipolar spindle was detec ted by immunofluorescence in p72-positive mitotic cells exhibiting a r egular or C-metaphase-like chromosome configuration. Electron-microsco pic study of C-metaphase-like cells revealed alteration of the centros ome structure which is characterized by the following features: (1) br eakdown of the diplosome, (2) separation of the fibrillar material fro m centrioles, and (3) disruption of the centriolar cylinder. The spind le pole in the aberrant mitotic cells consisted of one or several foci of microtubules converging on the fibrillar aggregates. There are not any signs of the nuclear envelope reconstruction found in mitotic cel ls with highly condensed scattered chromosomes. Unlike in HEL cells, v iral particles were not detected in Vero cells. A question arises as t o whether centrosome injury is an integral part of the events leading to cell death unrelated to the reproduction of HCMV. (C) 1997 Academic Press.