Attenuated Bordetella Strains

Abstract

A mutated Bordetella strain comprising at least a mutated ptx gene, a deleted or mutated dnt gene and a heterologous ampG gene is provided. The attenuated mutated Bordetella strain can be used in an immunogenic composition or a vaccine for the treatment or prevention of a Bordetella infection. Use of the attenuated Bordetella strain for the manufacture of a vaccine or immunogenic composition, as well as methods for protecting mammals against infection by Bordetella are also provided.

What is claimed is: 
     
         1 . A method of inducing a mucosal immune response in a subject, the method comprising colonizing the mucosa of a subject with a live attenuated  Bordetella pertussis  strain comprising at least a mutated pertussis toxin (ptx) gene, a deleted or mutated dermonecrotic (dnt) gene, and a heterologous ampG gene replacing the  Bordetella  ampG gene. 
     
     
         2 . The method of  claim 1 , wherein the subject is a newborn or a child. 
     
     
         3 . The method of  claim 1 , wherein the live attenuated  Bordetella  strain is administered to the respiratory tract. 
     
     
         4 . The method of  claim 3 , wherein the live attenuated  Bordetella  strain is administered intranasally. 
     
     
         5 . The method of  claim 1 , wherein the live attenuated  Bordetella  strain is a BPZE1 strain deposited with the Collection Nationale de Culture Microorganismes as accession number 1-3585. 
     
     
         6 . The method of  claim 1 , wherein the live attenuated  Bordetella  strain expresses less than 5% residual tracheal cytotoxin (CTC) activity.