Self-Adjuvanting Adenoviral Nanovaccine for Effective T-Cell-Mediated Immunity and Long-Lasting Memory Cell Activation against Tuberculosis

• Published in: ACS infectious diseases Vol. 10; no. 11; p. 3939
• Main Authors: Sowndharya, Chithaiyan Kamaladevi, Mehnath, Sivaraj, Ponbharathi, Arivalagan, Jeyaraj, Murugaraj
• Format: Journal Article
• Language: English
• Published: United States 28.10.2024
• Subjects: Mycobacterium smegmatis; nanovaccine; adenovirus hexon protein; dendritic cells; memory cells; tuberculosis
• ISSN: 2373-8227; 2373-8227
• DOI: 10.1021/acsinfecdis.4c00619

An enhanced vaccine is immediately required to swap the more than 100 year-old bacillus Calmette-Guerin (BCG) vaccine against tuberculosis. Here, trimethyl chitosan-loaded inactivated (MST), along with potent adenovirus hexon protein (AdHP), and toll-like receptor (TLR)-1/2 as a nanovaccine, was developed against tuberculosis (TB). The nanoformulation increased the bioavailability of MST and elicited the targeting ability. Nanovaccines have a size range of 183.5 ± 9.5 nm with a spherical morphology and uniform distribution. The nanovaccine exhibited a higher release of antigen in acidic pH, and this is mainly due to protonation of ionizable groups in polymeric materials. The nanovaccine facilitated the effective cellular uptake of bone-marrow-derived dendritic cells and progressive endosomal escape in a shorter period. In vitro analyses indicated that the nanovaccine activated cytokine and T-cell production and also assisted in humoral immunity by producing antibodies. The nanovaccine was able to induce more cellular and humoral memory cells and a better protective immune response. Nanomaterials effectively delivered the MST, AdHP, and TLR1/2 antigens to the major histocompatibility complex class I and II pathways to generate protective cytotoxic CD8 and CD4 T-cells. In vivo experiments, compared with free MST and BCG, showed that mice immunized with the nanovaccine induced more specific CD4 , CD8 , and memory T-cell activations. Overall, the fabricated nanovaccine was able to control the release of antigens and adjuvants and enhance memory cell activation and humoral immunity against TB.