Further characterization of Japanese acellular pertussis vaccine prepared in 1988 by 6 Japanese manufacturers.

In 1974, we published a paper entitled "Leukocytosis-Promoting Factor of Bordetella pertussis. Its Identity with Protective Antigen". A preparation which was purified from the culture supernatant of Bordetella pertussis phase I, Tohama strain by consecutive steps of ammonium sulfate fractionation and sucrose density gradient centrifugation showed leukocytosis-promoting, histamine-sensitizing and hemagglutinating activities. The preparation consisted of two proteins: pertussis toxin (PT) and filamentous hemagglutinin (FHA). After treatment with formalin, this preparation elicited strong mouse protective activity. Passive protection tests in mice with the anti-PT and anti-FHA sera also showed that these sera had protective activity. According to these findings, Japanese manufacturers have succeeded in preparing an acellular pertussis vaccine containing PT toxoid and FHA as main protective antigens on a large scale. Acellular pertussis vaccine was introduced in 1981 as purified pertussis vaccine in Japan. Characteristics of this vaccine have been reported elsewhere in the last eight years. Further characterization of Japanese pertussis vaccines which were produced in 1988 by six manufacturers was carried out. There was no fundamental difference among the six products; each vaccine consisted of PT toxoid and FHA as the main protective antigens.