Comparison of human cytomegalovirus obtained by glycine extraction and by sonic disruption of infected cells.

The method of C. Hallauer and G. Kronauer (Arch. Ges. Virusforsch. 15:433, 1965) for extraction of cell-associated virus by treating infected monolayers with isotonic glycine buffer (pH 9) was applied to human cytomegalovirus. This procedure yields infectious cell-free virus and permits serial extractions of the same infected monolayers with no major damage to the cells. The properties of glycine-extracted virus in two different strains of human cytomegalovirus, AD 169 and C 87, were compared to those of intracellular virus obtained by sonic disruption of infected cells. Recent reports (V. Vonka and M. BenyeshMelnick, J. Bacteriol. 91:213, 1966; M. BenyeshMelnick et al., J. Immunol. 96:261, 1966; M. Benyesh-Melnick et al., J. Bacteriol. 92:1555, 1966) describe the procedures used for preparing extracellular and intracellular virus, and the methods of plaque assay, complement-fixation, and quantitative electron microscopy. Glycine-extracted virus. Infected monolayers in 16-oz (500-ml) bottles were washed with Hank's solution (pH 7.1) and flooded with 10 ml of 0.1