Delogu G.,Catholic University of the Sacred Heart |
Fadda G.,Catholic University of the Sacred Heart |
Brennan M.J.,Aeras Global TB Vaccine Foundation
Protein and Peptide Letters | Year: 2012
Among the few well characterized virulence factors of Mycobacterium tuberculosis (Mtb) is the heparinbinding hemagglutinin (HBHA). HBHA is a 21-kDa protein that localizes to the mycobacterial surface where it can interact with host components. Interaction with epithelial cells and components of the extracellular matrix is mediated by the methylated lysine-rich C-terminal domain of the protein. The N-terminal end of HBHA contains a coiled coil motif which is involved in protein oligomerization and bacterial-bacterial aggregation. In this report, we will focus our attention on what is known about the structure of the HBHA protein and the protein function and role in TB pathogenesis. © 2012 Bentham Science Publishers. Source
Mahomed H.,University of Cape Town |
Hawkridge T.,University of Cape Town |
Verver S.,KNCV Tuberculosis Foundation |
Abrahams D.,University of Cape Town |
And 6 more authors.
PLoS ONE | Year: 2011
Setting: This study was conducted in a high tuberculosis (TB) burden area in Worcester, South Africa, with a notified all TB incidence rate of 1,400/100,000. Main Objective: To compare the predictive value of a baseline tuberculin skin test (TST) with that of the QuantiFERON TB Gold (In-tube) assay (QFT) for subsequent microbiologically confirmed TB disease among adolescents. Methods: Adolescents aged 12-18 years were recruited from high schools in the study area. At baseline, blood was drawn for QFT and a TST administered. Participants were followed up for up to 3.8 years for incident TB disease (median 2.4 years). Results: After exclusions, 5244 (82.4%) of 6,363 adolescents enrolled, were analysed. The TB incidence rate was 0.60 cases per 100 person years (pyrs) (95% CI 0.43-0.82) for baseline TST positive (≥5 mm) participants and 0.64 cases per 100 pyrs (95% CI 0.45-0.87) for baseline QFT positive participants. TB incidence rates were 0.22 per 100 pyrs (0.11-0.39) and 0.22 per 100 pyrs (0.12-0.38) among those with a negative baseline TST and QFT respectively. Sensitivity for incident TB disease was 76.9% for TST and 75.0% for QFT (p = 0.81). Positive predictive value was 1.4% for TST and 1.5% for QFT. Conclusion: Positive TST and QFT tests were moderately sensitive predictors of progression to microbiologically confirmed TB disease. There was no significant difference in the predictive ability of these tests for TB disease amongst adolescents in this high burden setting. Therefore, these findings do not support use of QFT in preference to TST to predict the risk of TB disease in this study population. © 2011 Mahomed et al. Source
Hirao L.A.,University of Pennsylvania |
Hokey D.A.,Aeras Global TB Vaccine Foundation |
Morrow M.P.,University of Pennsylvania |
Morrow M.P.,Inovio Pharmaceuticals, Inc. |
And 2 more authors.
PLoS ONE | Year: 2011
Costimulatory molecules play a central role in the development of cellular immunity. Understanding how costimulatory pathways can be directed to positively influence the immune response may be critical for the generation of an effective HIV vaccine. Here, we evaluated the ability of intravenous administration of a blocking monoclonal antibody (mAb) directed against the negative costimulatory molecule CTLA-4, and an agonist mAb directed against the positive costimulatory molecule 4-1BB, either alone or in combination, to augment intramuscular SIV DNA immunizations. We then tested the ability these of these responses to impact a high-dose SIVmac251 challenge. Following immunization, the groups infused with the anti-4-1BB mAb exhibited enhanced IFN-γ responses compared to the DNA vaccine only group. Interestingly, although CTLA-4 blockade alone did not enhance IFN-γ responses it did increase the proliferative capacity of the CD4 + and CD8 + T cells. The combination of both mAbs enhanced the magnitude of the polyfunctional CD8 + T cell response. Following challenge, the group that received both mAbs exhibited a significant, ~2.0 log, decrease in plasma viral load compared to the naïve group the included complete suppression of viral load in some animals. Furthermore, the use of the CTLA-4 blocking antibody resulted in significantly higher viral loads during chronic infection compared to animals that received the 4-1BB mAb, likely due to the higher CD4 + T cell proliferative responses which were driven by this adjuvant following immunization. These novel studies show that these adjuvants induce differential modulation of immune responses, which have dramatically different consequences for control of SIV replication, suggesting important implications for HIV vaccine development. © 2011 Hirao et al. Source
Aeras Global Tb Vaccine Foundation | Date: 2014-06-24
Aeras Global Tb Vaccine Foundation | Date: 2013-04-08
Bacterial delivery systems with improved transgene expression are provided. The recombinant bacterial delivery systems deliver transgenes of interest and suppressors of the eukaryotic Type I interferon response to eukaryotic cells. Suppression of the eukaryotic Type I interferon response allows improved expression of the encoded transgene.