Properties of an acellular preparation of Bordetella pertussis and its analysis after centrifugation in saccharose gradient

: Acellular preparations were studied which were obtained by a method of acidic extraction from culture of strain Tohama of Bordetella pertussis. Obtained preparations EM I and EM II were exhibiting property of leukocytosis stimulation and were respectively of following values: 43.5 and 19 u LPF/mg of protein. They also caused hemagglutination (150 and 19 u HA/mg of protein). Both preparations were exhibiting protective effect in intracerebral test performed on mice. After differentiation of EM I preparation by preparative centrifugation in saccharose gradient two fractions were obtained, of which lighter was exhibiting high hemagglutinating activity and leukocytosis stimulation (198 u LPF/mg of protein). Heaver fraction contained mainly endotoxin. Applied method permitted for partial purification of acellular preparation of B. pertussis; mainly decrease in its content of endotoxin responsible for high reactogenicity of pertussis vaccines.