Final answer:
Purified protein from Bordetella pertussis is used in a subunit vaccine, which exposes individuals to key antigens of the pathogen rather than the entire organism.
Step-by-step explanation:
Purified protein from Bordetella pertussis is used in a subunit vaccine. Subunit vaccines utilize only the key antigens of a pathogen, not the whole cells or viruses, which are either isolated through chemical degradation of the pathogen or produced through genetic engineering. The purified 68 kDa outer membrane protein found in the virulent strain of Bordetella bronchi septica and cloned in an avirulent strain or another host can lead to producing cost-effective subunit vaccines.
These vaccines, such as DTaP and Tdap, contain acellular components with antigens that stimulate an immune response without the presence of the whole pathogen. This method is distinct from the production of toxoid vaccines (which are inactivated bacterial toxins), live attenuated or inactivated vaccines (which use weak, killed, or inactivated whole pathogens), and conjugate vaccines (which have a protein conjugated to a capsule polysaccharide to enhance immune responses in children).