This page has moved. Click here to view. PT is composed of several subunits and has a structure similar to other bacterial toxins such as diphtheria. When administered to mice, PT induces antibodies that protect against lethal respiratory and intracerebral challenge with live B pertussis organisms.
Many investigators believe PT has a central role in providing clinical protection for humans.
Mice immunized with FHA are protected against lethal respiratory challenge with pertussis but not against intracerebral challenge. Agglutinogens are fimbrialassociated surface components that stimulate production of agglutinating antibodies. Recently, several clinical trials compared the efficacy of acellular vaccines and conventional whole-cell vaccines . Because the Italian and Swedish trials used a standardized protocol, the data from these two studies can be compared directly. All of the vaccines that contained three or more components were equally effective, affording general, most of the acellular vaccines were highly effective.