Enhancement of immune responses using ovalbumin‐conjugatedEucommia ulmoides leaf polysaccharides encapsulated in a cubic liquid‐crystalline phase delivery system

Abstract

BACKGROUND: To improve the adjuvant activity of polysaccharides from Eucommia ulmoides leaves (PsEUL) in inducing an effective immune response against ovalbumin (OVA), PsEUL were conjugated to OVA using the N-(3-dimethylaminopropyl)-N 0 -ethylcarbodiimide hydrochloride (EDC) method. The synthesized PsEUL-OVA was encapsulated using phytantriol and F127 to produce PsEUL-OVA cubosomes (Cubs), a novel delivery system. The physicochemical properties and immune modulation effects of this novel delivery system were explored. RESULTS:In vitro, PsEUL-OVA/Cubs carrying large amounts of OVA were rapidly phagocytized by macrophages and upregulated macrophage proliferation, thereby stimulating cytokine production (interleukin (IL)-6 and IL-4). In vivo, PsEUL-OVA/Cubs increased the titer of OVA-specific antibodies (immunoglobulin (Ig)G, IgG2b, IgG2a and IgG1) and cytokine levels (IL-2, IL-6, IL-4 and interferon-γ). In addition, the cubosomes promoted the differentiation of CD8 + and CD4 + T cells in the spleen and the maturation of dendritic cells (DCs). These results indicated that PsEUL-OVA/Cubs stimulated both cellular and humoral immune responses by enhancing the phagocytic activity of DCs and macrophages and increasing the antigen presentation efficiency. CONCLUSION: Collectively, the findings demonstrate that PsEUL-antigen/Cubs can be a useful delivery vehicle with immune response-promoting effects. Therefore, this study lays the foundation for the development of novel adjuvant-antigen delivery systems with potential applications in vaccine design.

Polysaccharides from Eucommia ulmoides Oliv. Leaves Alleviate Acute Alcoholic Liver Injury by Modulating the Microbiota–Gut–Liver Axis in Mice

“…Moreover, there are studies that show that an imbalance in intestinal flora is a pivotal factor in the initiation and progression of alcoholic liver injury [6,7]. Recently, polysaccharides have garnered a lot of attention in alcohol liver injury due to their varied actions, such as anti-inflammation, antioxidant, anti-tumor, and enhancement of immune activity [8][9][10][11][12][13][14][15], as well as the ability to regulate the gut microbiota, thereby exerting positive efforts on host health [16,17].…”