Mechanistic investigation of calcium phosphate mineralization potentiating the cellular immune response of foot-and-mouth disease virus-like particle vaccines

ions and an increase in lysosomal permeability. This facilitates the escape of VLPs into the cytoplasm for cross-presentation. Furthermore, CaP mineralization enhanced the level of activation of DCs by FMDV VLPs, evidenced by elevated expression of CD40 and CD86, and the secretion of IL-2 and IL-12p70. Immunization studies in mice revealed that VLPs-CaP elicited higher levels of specific antibodies compared to unmineralized VLPs; notably, there was an increased IgG2a/IgG1 ratio along with a greater number of cytotoxic T lymphocytes (CTLs). This study elucidated the mechanism by which CaP-mineralized VLPs induce cellular immune responses, offering new insights and strategies aimed at enhancing the cellular immune efficacy of VLP-based vaccines that primarily elicit humoral immunity.