Vaccination remains the most effective strategy for preventing infectious diseases. Subunit vaccines, which consist of antigenic components derived from pathogens, offer significant advantages in terms of biosafety, ease of preparation, and scalability. However, subunit vaccines often exhibit lower immunogenicity than whole-pathogen vaccines do. To address this limitation, coupling antigens with nanoparticles has emerged as a promising strategy for enhancing immune responses by mimicking pathogen structures and improving antigen presentation. This study evaluated the stability of ferritin (F-nps) and encapsulin (E-nps) nanoparticles and their efficient uptake by bone-marrow-derived dendritic cells (BMDCs) in vitro. In vivo studies demonstrated their effective targeting of lymph nodes. The African swine fever virus C129R protein was conjugated to ferritin and encapsulin nanoparticles to assess its ability to enhance antigen-specific immune responses. In murine models, both F-nps and E-nps significantly increased the immunogenicity of the C129R antigen, highlighting their potential as effective vaccine delivery systems. These findings underscore the promise of ferritin and encapsulin nanoparticles as delivery platforms for enhancing antigen immunogenicity and pave the way for the development of nanoparticle-based vaccines.

Weaning stress damages the intestines and disrupts the intestinal barrier in piglets, which significantly impacts the pig farming industry’s economy. We aimed to examine the effects of ShenQiGan extract (CAG) on intestinal barrier function and explore the underlying molecular mechanisms in stress-challenged weaned piglets. The experimental design involved 80 weaned piglets aged 28 days (with an average body weight of 7.78 ± 0.074 kg) that were randomly allocated into four groups: Control, LCAG (0.1% CAG), MCAG (0.5% CAG), and HCAG (1.0% CAG). After a 28-day trial period, the growth performance and incidence of diarrhea in piglets were evaluated. CAG increased the average daily gain of weaned piglets, reduced the feed-to-gain ratio, and decreased the incidence of diarrhea. It significantly lowered serum inflammatory cytokine levels while elevating immunoglobulin levels. The supplement notably enhanced concentrations of acetic acid, propionic acid, butyric acid, and isobutyric acid. Furthermore, CAG demonstrated intestinal morphology restoration and upregulation of tight junction proteins and MUC2 protein expression in jejunum. At the mRNA level, it significantly upregulated the expression of Occludin, Claudin1, and MUC2 genes. CAG improves growth performance and mitigates diarrhea in weaned piglets by enhancing intestinal barrier integrity, modulating systemic inflammatory responses, elevating immunoglobulin levels, and promoting short-chain fatty acids (SCFAs) production in the cecum.