Promotion of Cellular and Humoral Immunity against Foot-and-Mouth Disease Virus by Immunization with Virus-Like Particles Encapsulated in Monophosphoryl Lipid A and Liposomes

Abstract

Virus-like particles (VLPs) have emerged as promising vaccine candidates against foot-and-mouth disease (FMD). However, such vaccines provide a relatively low level of protection against FMD virus (FMDV) because of their poor immunogenicity. Therefore, it is necessary to design effective vaccine strategies that induce more potent immunogenicity. In order to investigate the means to improve FMD VLP vaccine (VLPFMDV) immunogenicity, we encapsulated VLPs (MPL/DDA-VLPFMDV) with cationic liposomes based on dimethyldioctadecylammonium bromide (DDA) and/or monophosphoryl lipid A (MPL, TLR4 agonist) as adjuvants. Unlike inactivated whole-cell vaccines, VLPFMDV were successfully encapsulated in this MPL/DDA system. We found that MPL/DDA-VLPFMDV could induce strong cell-mediated immune responses by inducing not only VLP-specific IFN-γ+CD4+ (Th1), IL-17A+CD4+ (Th17), and IFN-γ+CD8+ (activated CD8 response) T cells, but also the development of VLP-specific multifunctional CD4+ and CD8+ memory T cells co-expressing IFN-γ, TNF-α, and IL-2. In addition, the MPL/DDA-VLPFMDV vaccine markedly induced VLP-specific antibody titers; in particular, the vaccine induced greater Th1-predominant IgG responses than VLPFMDV only and DDA-VLPFMDV. These results are expected to provide important clues for the development of an effective VLPFMDV that can induce cellular and humoral immune responses, and address the limitations seen in current VLP vaccines for various diseases.

Correlation between 146S Antigen Content in Foot-and-Mouth Disease Inactivated Vaccines and Immunogenicity Level and Vaccine Potency Alternative Test Methods

“…IFN-γ plays a crucial role in this immune response by activating macrophages and natural killer (NK) cells to combat FMDV [31]. Research has shown that measuring the level of IFN-γ released by FMDV-specific T cells has the potential to replace the challenge test in assessing the effectiveness of FMD vaccines [32].…”

Liposomal delivery system/adjuvant for tuberculosis vaccine

“…There is no doubt that liposomal components of mycobacterial lipids can induce potent humoral and cellular immune responses to both mycobacterial and nonmycobacterial antigens 74 . The lipid extract of mycobacteria consists of various lipids separated by thin‐layer chromatography and immunostimulatory molecules.…”

“…73 There is no doubt that liposomal components of mycobacterial lipids can induce potent humoral and cellular immune responses to both mycobacterial and nonmycobacterial antigens. 74 The lipid extract of mycobacteria consists of various lipids separated by thin-layer chromatography and immunostimulatory molecules. One advantage of using complicated instructions for vaccine administration is to activate many portions of the proinflammatory cascade, which leads to broader and longer-lasting biological activity.…”

Biological Nanoparticles in Vaccine Development

“…Both VLPs and OMVs have been studied for encapsulation and release from larger ordered structures, with the encapsulating agents in more recent years mainly being polymer-based ( Watkins et al, 2017a ; Jamaledin et al, 2020 ; Pastor et al, 2020 ; Gomes et al, 2021 ), and although liposomes have also been used ( Kim et al, 2020 ) ( Table 4 ).…”