Human serum antibody responses to Bordetella pertussis infection and pertussis vaccination

We used an immunoblotting technique to compare the serum antibody responses to pertussis toxin (PT), filamentous hemagglutinin (FHA), a 69-kilodalton (kDa) adenylate cyclase-associated protein (69 KD protein), and Bordetella pertussis outer membrane proteins (OMPs) following either B. pertussis infection or immunization with whole-cell pertussis vaccine. Infection and vaccination induced nearly equally intense antibody responses to PT and to FHA, but vaccination induced stronger antibody responses to the 69 KD protein and to many OMPs. The importance of serum antibody responses to the 69 KD protein and to B. pertussis OMPs other than PT and FHA in conferring immunity to pertussis after vaccination is unknown. Serum antibody responses to PT following either infection or vaccination were almost exclusively to the 28-kDa enzymatic subunit (S1) and only rarely and weakly to the lesser molecular weight binding subunits (S2-S5).