Serospecific protection of mice against intranasal infection with Bordetella pertussis

The ability of purified serospecific agglutinogens from Bordetella pertussis to protect mice against intranasal infection has been examined. Immunization with agglutinogen 2 protected mice against infection with 1.2.0 or 1.2.3 serotypes of B. pertussis, whereas immunization with agglutinogen 3 protected mice against infection with all serotypes. More importantly immunization with serospecific agglutinogen resulted in immune selection so that organisms recovered following infection did not express the immunizing antigen. The results are consistent with the suggestions that protection of children with whole cell pertussis vaccine is to some extent serospecific and that agglutinogens should be considered as constituents of acellular pertussis vaccines.