g To generate a vaccine to pertussis toxin, a heat-killed preparation of Bordetella pertussis (the bacteria that produce pertussis toxin) is mixed with a purified preparation of the inactivated toxin protein. The mixture is then injected subcutaneously into mice. In an effort to enhance the antibody response to the toxin, a group of test mice is depleted of all their dendritic cells immediately prior to immunization. However, instead of enhancing the antibody response, the dendritic cell depletion nearly eliminated the anti-toxin antibody response because why