Biophysical Studies of Respiratory Syncytial Virus I. Density of Respiratory Syncytial Virus and Associated Complement-Fixing Antigens in a Cesium Chloride Density Gradient

Abstract

Coates, Helen V. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), Ben R. Forsyth, and R. M. Chanock . Biophysical studies of respiratory syncytial virus. I. Density of respiratory syncytial virus and associated complement-fixing antigens in a cesium chloride density gradient. J. Bacteriol. 91: 1263–1269. 1966.—Concentrated fluids from respiratory syncytial (RS) virus-infected tissue cultures (HEp-2 and BEK) were subjected to equilibrium sedimentation in cesium chloride. When two antigenically distinct strains of RS virus (Long and 18537) were tested, approximately 90% of the infectious virus was recovered in a sharp, symmetrical peak with a density of 1.22 to 1.24. In a similar study, unconcentrated virus had a density of 1.25 to 1.27. Two immunologically distinguishable complement-fixing antigens (antigens A and B) were detected at densities of 1.28 to 1.32 and 1.23 to 1.37. In addition, the existence of a third antigen (density of 1.22 to 1.30) was suggested. The possible origin of these antigens is discussed relative to the known properties of RS virus and the other myxoviruses.