title: T- and B-cell-mediated protection induced by novel, live attenuated pertussis vaccine in mice. Cross protection against parapertussis.
abstract: BACKGROUND
  Despite the extensive use of efficacious vaccines, pertussis still ranks among the major causes of childhood mortality worldwide. Two types of pertussis vaccines are currently available, whole-cell, and the more recent acellular vaccines. Because of reduced reactogenicity and comparable efficacy acellular vaccines progressively replace whole-cell vaccines. However, both types require repeated administrations for optimal efficacy. We have recently developed a live attenuated vaccine candidate, named BPZE1, able to protect infant mice after a single nasal administration.
  
  
  RESULTS
  We determined the protective mechanism of BPZE1-mediated immunity by using passive transfer of T cells and antibodies from BPZE1-immunized mice to SCID mice. Clearance of Bordetella pertussis from the lungs was mediated by both BPZE1-induced antibodies and CD4(+), but not by CD8(+) T cells. The protective CD4(+) T cells comprised IFN-gamma-producing and IL-17-producing subsets, indicating that BPZE1 induces both Th1 and Th17 CD4(+) T cells. In addition, and in contrast to acellular pertussis vaccines, BPZE1 also cross-protected against Bordetella parapertussis infection, but in this case only the transfer of CD4(+) T cells conferred protection. Serum from BPZE1-immunized mice was not able to kill B. parapertussis and did not protect SCID mice against B. parapertussis infection.
  
  
  CONCLUSIONS
  The novel live attenuated pertussis vaccine BPZE1 protects in a pre-clinical mouse model against B. pertussis challenge by both BPZE1-induced antibodies and CD4(+) T cell responses. It also protects against B. parapertussis infection. However, in this case protection is only T cell mediated.
authors.affiliation: Inserm U1019, Lille, France.
authors.forename: Pascal Feunou
authors.initials: PF
authors.lastname: Feunou
authors.forename: Julie
authors.initials: J
authors.lastname: Bertout
authors.forename: Camille
authors.initials: C
authors.lastname: Locht
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D056738:Cross Protection; D004353:Drug Evaluation, Preclinical; D051379:Mice; D010567:Pertussis Vaccine / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000276:immunology*; D014613:Vaccines, Attenuated
chemical_list: D010567:Pertussis Vaccine; D014613:Vaccines, Attenuated