EN
Fixed rabies virus was freed from the brain of infected sheep by homogenization, freezing and thawing, sonication, and claryfying centrifugation (9150 X g for 10 min) of the tissue. The virus present in supernatant fluid was sedimented on a 50 per cent sucrose in the BXIV rotor (90,000 X g for 2 hours) to obtain its appropriate concentration. The concentrated virus was treated with 0.3 per cent saponin to separate haemagglutinins which were afterwards purified and concentrated by centrifugation in a caesium chloride gradient (280.000 X g for 8 hours). Separation of the haemagglutinins and nucleocapsids was checked by electron microscopic examination and determination of infectivity and haemagglutinating activity of fractions obtained in the gradient. The highest haemagglutinating and immunogenic activities, with lack of infectivity, was found in a fraction of a 1.28 g/ml density. Electron microscopy confirmed the separation of the haemagglutinins and nucleocapsids of the virus.