Cell Cycle-related Morphological Changes of Feline Lymphoid Cells as Revealed by Electron Microscopy1

The aim of this study was to correlate morphological changes in cells to known phases of the cell cycle. For this purpose, feline lymphoblastoid cells (FL74) chronically infected with feline leukemia virus were synchronized and examined by scanning and transmission electron microscopy. Scanning electron microscopy revealed that the cell surface underwent distinct changes which were found to be cell cycle specific. Morphological changes shown by transmission electron mi croscopy were used as ultrastructural markers to confirm the findings made by scanning electron microscopy relating to the various phases of the cell cycle. The results of these experi ments suggest that the presence of morphologically mixed populations of cells in many lymphoproliferative disorders, which had been described previously, may be explained by normal cell cycle-dependent variations.