Tuberculosis (TB) is one of the deadliest diseases, causing ∼2 million deaths annually worldwide. Mycobacterium bovis bacillus Calmette-Guérin (BCG), the only TB
vaccine in common use, is effective against disseminated and meningeal TB in young children but is not effective against adult pulmonary TB. T helper 1 (Th1) cells producing
interferon gamma (IFN-γ) and Th17 cells producing
interleukin-17 (IL-17) play key roles in host protection against TB, whereas Th2 cells producing
IL-4 and regulatory T cells (Tregs) facilitate TB
disease progression by inhibiting protective Th1 and Th17 responses. Furthermore, the longevity of
vaccine efficacy critically depends on the magnitude of long-lasting central memory T (TCM) cell responses. Hence,
immunomodulators that promote TCM responses of the Th1 and Th17 cell lineages may improve
BCG vaccine efficacy. Here, we show that
curcumin nanoparticles enhance various antigen-presenting cell (APC) functions, including autophagy, costimulatory activity, and the production of inflammatory
cytokines and other mediators. We further show that
curcumin nanoparticles enhance the capacity of BCG to induce TCM cells of the Th1 and Th17 lineages, which augments host protection against TB
infection. Thus,
curcumin nanoparticles hold promise for enhancing the efficacy of TB
vaccines.