Antigenic Characterization of Infectious Bronchitis Virus

Abstract

Three antigenically distinct soluble antigens (1–3) are associated with infectious bronchitis virus. The antigens are smaller than the virion. Antigens 1 and 3 are destroyed at 100°C, whereas antigen 2 is not. Antigen 2 is a ribonucleoprotein. The virus is sensitive to ether and sodium deoxycholate. Antigens released by treatment of purified virus with ether are identical to antigens in viral allantoic fluid and in virus-infected CAM. The virus has a buoyant density of 1.2289 g/ml in cesium chloride, whereas antigens 1 and 2 have buoyant densities of 1.14 and 1.18 g/ml, respectively.