Induction of protective immunity for Bordetella pertussis by nasal inoculation of pertussis vaccine in mice

Abstract

Although nasal vaccination has emerged as an interesting alternative to intramuscular or oral vaccination, knowledge is scarce about the immune responses after such immunization. In the present study, we inoculated purified Pertussis Toxin (PT) and Filamentous Haemagglutinin (FHA) with or without adjuvant (kayexalate), or Diphtheria acellular Pertussis Tetanus (DaPT) combined vaccine to mice intranasally three times every four weeks to investigate the references of the immunoresponses between nasal and intramuscular vaccination. The levels of pertussis specific serum IgG antibodies (Abs) and secretory IgA Abs in the nasal wash were measured by ELISA, and cytotoxic T cell activities were examined by proliferative response, and compared with the result from intramuscular inoculation. We also studied the efficacy of adjuvant in the nasal vaccination. The intramuscular inoculation of pertussis vaccine induced serum IgG antibodies and cellular immunity against PT and FHA, but did not induce local IgA antibodies. On the other hand, the nasal inoculation induced both serum and local antibody responses. Moreover, it also induced significant cellular immunity to pertussis antigen. In nasal vaccination, the inoculation with adjuvant was superior to inoculation without adjuvant for the induction of both humoral and cellular immunity.