Fusion of cytomegalovirus infected fibroblasts to form multinucleate giant cells.

Multinucleate giant cells have been observed to arise by cell fusion in cultures of human embryonic fibroblasts infected with human cytomegalovirus (CMV), strain AD 169. The infected cells develope intranuclear and intracytoplasmic inclusions and began to fuse three to four days postinfection when the majority of the cells were showing signs of a cytopathic effect.