Abstract:
The mucosal barrier and scavenging effect of the mucosal layer are two main obstacles in inducing mucosal immunization. To overcome these obstacles, we synthesized a bio-inspired mucoadhesive material, chitosan-catechol (ChiC), for surface modification of inactive porcine epidemic diarrhea virus (PEDV). Studies have revealed that PEDV particles can be facilely and mildly modified by Chi-C forming Chi-C-PEDV nanoparticles (Chic-Ps) through the covalent and electrostatic bond, which effectively prolongs the retention time of PEDV in the nasal mucosa. The cell co-culture model demonstrated that Chic-Ps exhibit enhanced recruitment of dendritic cells via the secretion of stimulating chemokine CCL20 and improving antigen permeability by disruption the distribution of ZO-1 protein in epithelial cells. Additionally, the flow cytometry (FCM) analysis revealed that Chic-Ps facilitate trafficking to lymph nodes and induce stronger cellular and humoral immune responses compared to unmodified PEDV. Notably, Chic-Ps induced a higher level of PEDV neutralizing antibody was induced by Chic-Ps in the nasal washes, as confirmed by a plaque reduction neutralization test. These results demonstrate that Chi-C is a promising nasal delivery system for vaccines. Proof of principle was obtained for inactivated PEDV, but similar delivery mechanisms could be applied in other vaccines when intranasal administration is needed.
摘要:
粘膜层的粘膜屏障和清除作用是诱导粘膜免疫的两个主要障碍。为了克服这些障碍,我们合成了一种受生物启发的粘膜粘附材料,壳聚糖-邻苯二酚(ChiC),用于非活性猪流行性腹泻病毒(PEDV)的表面修饰。研究表明,通过Chi-C形成Chi-C-PEDV纳米颗粒(Chic-Ps),可以通过共价键和静电键轻松温和地修饰PEDV颗粒,有效延长PEDV在鼻黏膜中的滞留时间。细胞共培养模型表明,Chic-P通过分泌刺激趋化因子CCL20并通过破坏ZO-1蛋白在上皮细胞中的分布来改善抗原通透性,从而增强了树突状细胞的募集。此外,流式细胞术(FCM)分析显示,与未修饰的PEDV相比,Chic-Ps促进运输到淋巴结并诱导更强的细胞和体液免疫反应。值得注意的是,Chic-Ps诱导较高水平的PEDV中和抗体由Chic-Ps在鼻洗液中诱导,通过斑块减少中和试验证实。这些结果表明,Chi-C是用于疫苗的有前景的鼻递送系统。获得了灭活PEDV的原理证明,但是当需要鼻内给药时,类似的递送机制可以应用于其他疫苗。