EVALUATION OF PLASMID-BASED ALPHAVIRUS REPLICONS ENCODING A MYCOBACTERIAL GENE FUSION AS EFFECTIVE IMMUNOGENS AGAINST TUBERCULOSIS
Document Type
Presentation
Start Date
22-10-2010 3:00 PM
End Date
22-10-2010 4:30 PM
Description
Background: New and improved vaccination strategies are needed to address the increasing global burden of tuberculosis (TB). In the present study we evaluated a novel gene delivery vector system -DNA launched alphavirus replicons encoding selected mycobacterial antigens in terms of their immunogenicity either alone or in a heterologous prime-boost strategy with adenovirus (Ad) vaccine vectors. Our previous studies have shown that a-crystallin (Acr) may represent an attractive target for prophylactic immunity against TB. A novel immunogen consisting of a fusion of Acr and AgSSB inycobacterial genes was generated and cloned into plasmid-based Venezuelan Equine Encephalitis virus replicons (Vrep) and Ad vectors. Methods:, Balb/c mice were immunized intramuscularly with Vrep-Acr/AgSSB at weeks Oand 3, sacrificed at week 6 and splenocytes harvested for assay. Since TB is transmitted primarily via the aerosol route, intranasal boosting with Ad-Acr/AgSSB was performed in some Vrep-primed mice in attempts to enhance Vrep-induced immunity and to focus responses at pulmonary sites of infection. Results & Conclusions: Two doses of Vrep-Acr/AgSSB appear to represent an effective gene delivery system for the induction of TB-specific immunity. Strong, antigen specific CD4+ and CDS+ T cell responses were induced against Acr and AgSSB. In combination with intranasal Ad boosting, Vreps show potential for the development of gene-based vaccines for both mucosal (pulmonary) and circulating immunity against TB infection. Mucosal prime boosting generated potent, multifunctional CD4+ and CDS+ T cell responses (IFNy+, TNFa+, IL-2+) in the spleen and in lung lymphoid tissues against both fusion antigens, indicative of high quality TBspecific immunity,. Studies of their protective efficacy are underway in a mouse model of pulmonary TB infection.
Recommended Citation
Dalmia, Neha; Mehta, Heena; Huang, Weitao; and Mason, Carol, "EVALUATION OF PLASMID-BASED ALPHAVIRUS REPLICONS ENCODING A MYCOBACTERIAL GENE FUSION AS EFFECTIVE IMMUNOGENS AGAINST TUBERCULOSIS" (2010). Dr. Joseph M. Moerschbaecher, III Graduate Research Day. 6.
https://digitalscholar.lsuhsc.edu/grad_rs/2010/poster2/6
EVALUATION OF PLASMID-BASED ALPHAVIRUS REPLICONS ENCODING A MYCOBACTERIAL GENE FUSION AS EFFECTIVE IMMUNOGENS AGAINST TUBERCULOSIS
Background: New and improved vaccination strategies are needed to address the increasing global burden of tuberculosis (TB). In the present study we evaluated a novel gene delivery vector system -DNA launched alphavirus replicons encoding selected mycobacterial antigens in terms of their immunogenicity either alone or in a heterologous prime-boost strategy with adenovirus (Ad) vaccine vectors. Our previous studies have shown that a-crystallin (Acr) may represent an attractive target for prophylactic immunity against TB. A novel immunogen consisting of a fusion of Acr and AgSSB inycobacterial genes was generated and cloned into plasmid-based Venezuelan Equine Encephalitis virus replicons (Vrep) and Ad vectors. Methods:, Balb/c mice were immunized intramuscularly with Vrep-Acr/AgSSB at weeks Oand 3, sacrificed at week 6 and splenocytes harvested for assay. Since TB is transmitted primarily via the aerosol route, intranasal boosting with Ad-Acr/AgSSB was performed in some Vrep-primed mice in attempts to enhance Vrep-induced immunity and to focus responses at pulmonary sites of infection. Results & Conclusions: Two doses of Vrep-Acr/AgSSB appear to represent an effective gene delivery system for the induction of TB-specific immunity. Strong, antigen specific CD4+ and CDS+ T cell responses were induced against Acr and AgSSB. In combination with intranasal Ad boosting, Vreps show potential for the development of gene-based vaccines for both mucosal (pulmonary) and circulating immunity against TB infection. Mucosal prime boosting generated potent, multifunctional CD4+ and CDS+ T cell responses (IFNy+, TNFa+, IL-2+) in the spleen and in lung lymphoid tissues against both fusion antigens, indicative of high quality TBspecific immunity,. Studies of their protective efficacy are underway in a mouse model of pulmonary TB infection.
Comments
See abstract book page 50