Abstract: The invention provides compositions and methods for preventing, treating and diagnosing infection by Salmonella enterica serovar typhi (S. typhi) and/or S. paratyphi, i.e., typhoid fever.

Abstract: The invention provides compositions and methods for using PltA, PltB, CdtB, or a mutant thereof, in inducing or enhancing an immune response.

Abstract: The invention provides compositions and methods for preventing, treating and diagnosing infection by Salmonella enterica serovar typhi (S. typhi) and/or S. paratyphi, i.e., typhoid fever.

Abstract: The invention provides compositions and methods for using PltA, PltB, CdtB, or a mutant thereof, in inducing or enhancing an immune response.

Abstract: The invention provides compositions and methods for preventing, treating and diagnosing infection by Salmonella enterica serovar typhi (S. typhi) and/or S. paratyphi, i.e., typhoid fever.

Abstract: The invention relates to the use of the type III secretion system of bacteria to stimulate immune responses against tumor antigen(s) for treating antigen-loss variant tumors. Methods are provided for stimulating and/or increasing an immune response against tumor antigens. The invention also relates to the preparation of antigen presenting cells from peripheral blood mononuclear cells using bacteria having a type III secretion system.

Abstract: The invention relates to the use of the type III secretion system of bacteria to stimulate immune responses against tumor antigen(s) for treating antigen-loss variant tumors. Methods are provided for stimulating and/or increasing an immune response against tumor antigens. The invention also relates to the preparation of antigen presenting cells from peripheral blood mononuclear cells using bacteria having a type III secretion system.

Abstract: Provided is a signal peptide comprising an amino acid sequence at least 90% homologous to the amino acid sequence as shown in SEQ ID NO:1. Further provided is a fusion protein comprising the signal peptide fused to a heterologous protein. Also provided are nucleic acid molecules encoding the signal peptide and encoding the fusion protein, as well as vectors and recombinant host cells comprising the nucleic acid molecules. The recombinant host cell can be a recombinant bacterium having a functional type III secretion system and having loss-of-function mutations in genes that encode secreted substrate proteins of the type III secretion system. The recombinant host cell can be used in a method of producing the heterologous protein.

Abstract: Provided is a method of stimulating a class I-restricted immune response to a protein of interest or antigenic portion thereof in a host, as well as a protein delivery vehicle for use in the method. A nucleic acid molecule encoding the protein of interest or antigenic portion thereof is introduced into an avirulent Salmonella spp., such that the resulting Salmonella encodes a chimeric protein comprising the protein of interest or antigenic portion thereof and an injectable protein which is a target of a type III secretion system or an injectable portion thereof. This resulting Salmonella can be introduced into a host, in which the Salmonella will inject the chimeric protein into the cytosol of the cells of the host. The injection of the chimeric protein results in the stimulation of a class I-restricted immune response to the protein of interest or antigenic portion thereof in the host.