EVALUATION OF TOLL LIKE RECEPTOR 5 LIGAND AS A SYSTEMIC AND MUCOSAL GENE-BASED VACCINATION ADJUVANT.
Document Type
Presentation
Start Date
22-10-2010 3:00 PM
End Date
22-10-2010 4:30 PM
Description
PURPOSE: Toll-like receptors (TLRs) play an important role in the initiation of immune responses. Their ligands may therefore have adjuvant properties in vaccine or therapeutic settings. Flagellin, the ligand for toll-like receptor 5 (TLRSL) has been shown to boost specific antibody responses when conjugated to vaccine protein, e.g. flu hemagglutinin. Herein, we evaluate both the cellular and humoral adjuvant properties of flagellin in a gene-based vaccine setting.
METHODS: DNA vaccines and adenoviruses (Ad) encoding the mycobacterial protein AgSSB and/or flagellin were generated and tested for expression. Biological activity of vectorencoded flagellin was confirmed using THP1-Blue-CD14 cells. BALB/c mice were given Ad vaccines or DNA and Ad vaccines in prime-boost immunization. Body mass was monitored to assess morbidity and immune responses in spleen, pulmonary-associated lymph nodes, and lungs were tested by ELISpot, intracellular cytokine staining, and tetramer staining.
RESULTS: Intramuscular (IM) co-immunization with Ad-AgSSB and serial dilutions of Ad-flagellin led to enhanced AgSSB-specific CDS+ and dose dependent CD4+ T cell responses compared to immunization with Ad-AgSSB alone. In contrast, intranasal (IN) co-immunization led to unexpected decreases in mucosa! CD4+ and CDS+ T cell responses. By either route, flagellin induced a dose-dependent transient weight loss. In prime-boost immunization, priming with DNAAgSSB-flagellin and boosting with IM Ad-AgSSB led to enhanced AgSSB-specific CD4+ and CDS+ T cell responses that were better than priming and boosting with vaccines encoding AgSSB .alone. Intranasal boosting with Ad-AgSSB also enhanced mucosa! CD4+ and CDS+ T cell responses in mice primed with DNA-AgSSB-flagellin.
CONCLUSIONS: Flagellin clearly has the capacity to enhance AgSSB-specific systemic and mucosa! cellular immune response depending on the route of immunization. Studies are underway to clarify underlying mechanisms including the pulmonary effect of mucosa! priming with flagellin.
Recommended Citation
Rady, Hamada; Huang, Weitao; and Ramsay, Alistair J., "EVALUATION OF TOLL LIKE RECEPTOR 5 LIGAND AS A SYSTEMIC AND MUCOSAL GENE-BASED VACCINATION ADJUVANT." (2010). Dr. Joseph M. Moerschbaecher, III Graduate Research Day. 18.
https://digitalscholar.lsuhsc.edu/grad_rs/2010/poster2/18
EVALUATION OF TOLL LIKE RECEPTOR 5 LIGAND AS A SYSTEMIC AND MUCOSAL GENE-BASED VACCINATION ADJUVANT.
PURPOSE: Toll-like receptors (TLRs) play an important role in the initiation of immune responses. Their ligands may therefore have adjuvant properties in vaccine or therapeutic settings. Flagellin, the ligand for toll-like receptor 5 (TLRSL) has been shown to boost specific antibody responses when conjugated to vaccine protein, e.g. flu hemagglutinin. Herein, we evaluate both the cellular and humoral adjuvant properties of flagellin in a gene-based vaccine setting.
METHODS: DNA vaccines and adenoviruses (Ad) encoding the mycobacterial protein AgSSB and/or flagellin were generated and tested for expression. Biological activity of vectorencoded flagellin was confirmed using THP1-Blue-CD14 cells. BALB/c mice were given Ad vaccines or DNA and Ad vaccines in prime-boost immunization. Body mass was monitored to assess morbidity and immune responses in spleen, pulmonary-associated lymph nodes, and lungs were tested by ELISpot, intracellular cytokine staining, and tetramer staining.
RESULTS: Intramuscular (IM) co-immunization with Ad-AgSSB and serial dilutions of Ad-flagellin led to enhanced AgSSB-specific CDS+ and dose dependent CD4+ T cell responses compared to immunization with Ad-AgSSB alone. In contrast, intranasal (IN) co-immunization led to unexpected decreases in mucosa! CD4+ and CDS+ T cell responses. By either route, flagellin induced a dose-dependent transient weight loss. In prime-boost immunization, priming with DNAAgSSB-flagellin and boosting with IM Ad-AgSSB led to enhanced AgSSB-specific CD4+ and CDS+ T cell responses that were better than priming and boosting with vaccines encoding AgSSB .alone. Intranasal boosting with Ad-AgSSB also enhanced mucosa! CD4+ and CDS+ T cell responses in mice primed with DNA-AgSSB-flagellin.
CONCLUSIONS: Flagellin clearly has the capacity to enhance AgSSB-specific systemic and mucosa! cellular immune response depending on the route of immunization. Studies are underway to clarify underlying mechanisms including the pulmonary effect of mucosa! priming with flagellin.
Comments
See abstract book page 62