Abstract：
Avian influenza virus subtype H9N2 has the ability to infect birds and humans, further causing significant losses to the poultry industry and even posing a great threat to human health. Oral vaccine received particular interest for preventing majority infection due to its ability to elicit both mucosal and systemic immune responses, but their development is limited by the bad gastrointestinal (GI) environment, compact epithelium and mucus barrier, and the lack of effective mucosal adjuvants. Herein, we developed the dendritic fibrous nano-silica (DFNS) grafted with Cistanche deserticola polysaccharide (CDP) nanoparticles (CDP-DFNS) as an adjuvant for H9N2 vaccine. Encouragingly, CDP-DFNS facilitated the proliferation of T and B cells, and further induced the activation of T lymphocytes in vitro. Moreover, CDP-DFNS/H9N2 significantly promoted the antigen-specific antibodies levels in serum and intestinal mucosal of chickens, indicating the good ability to elicit both systemic and mucosal immunity. Additional, CDP-DFNS facilitate the activation of CD4 + and CD8 + T cells both in spleen and intestinal mucosal, and the indexes of immune organs. This study suggested that CDP-DFNS may be a new avenue for development of oral vaccine against pathogens that are transmitted via mucosal route.
摘要：
H9N2亚型禽流感病毒具有感染鸟类和人类的能力，进一步给家禽业造成重大损失，甚至对人类健康构成巨大威胁。口服疫苗因其引发粘膜和全身免疫反应的能力而在预防多数感染方面受到特别关注。但是它们的发育受到不良胃肠道（GI）环境的限制，致密上皮和粘液屏障，缺乏有效的粘膜佐剂。在这里，我们开发了树枝状纤维纳米二氧化硅（DFNS）与肉芽胞多糖（CDP）纳米颗粒（CDP-DFNS）接枝作为H9N2疫苗的佐剂。令人鼓舞的是，CDP-DFNS促进T细胞和B细胞的增殖,并在体外进一步诱导T淋巴细胞的活化。此外，CDP-DFNS/H9N2显著促进鸡血清和肠黏膜抗原特异性抗体水平,表明具有引起全身和粘膜免疫的良好能力。额外,CDP-DFNS促进脾和肠粘膜CD4+和CD8+T细胞的活化，和免疫器官的指标。这项研究表明，CDP-DFNS可能是开发针对通过粘膜途径传播的病原体的口服疫苗的新途径。
