Department of Cell Biology, The Scripps Research Institute, La Jolla, California, United States of America.
PLoS One. 2009 Nov 23;4(11):e7981. doi: 10.1371/journal.pone.0007981.
Plant viruses such as Cowpea mosaic virus (CPMV) are increasingly being developed for applications in nanobiotechnology including vaccine development because of their potential for producing large quantities of antigenic material in plant hosts. In order to improve efficacy of viral nanoparticles in these types of roles, an investigation of the individual cell types that interact with the particles is critical. In particular, it is important to understand the interactions of a potential vaccine with antigen presenting cells (APCs) of the immune system. CPMV was previously shown to interact with vimentin displayed on cell surfaces to mediate cell entry, but the expression of surface vimentin on APCs has not been characterized.
The binding and internalization of CPMV by several populations of APCs was investigated both in vitro and in vivo by flow cytometry and fluorescence confocal microscopy. The association of the particles with mouse gastrointestinal epithelium and Peyer's patches was also examined by confocal microscopy. The expression of surface vimentin on APCs was also measured.
We found that CPMV is bound and internalized by subsets of several populations of APCs both in vitro and in vivo following intravenous, intraperitoneal, and oral administration, and also by cells isolated from the Peyer's patch following gastrointestinal delivery. Surface vimentin was also expressed on APC populations that could internalize CPMV. These experiments demonstrate that APCs capture CPMV particles in vivo, and that further tuning the interaction with surface vimentin may facilitate increased uptake by APCs and priming of antibody responses. These studies also indicate that CPMV particles likely access the systemic circulation following oral delivery via the Peyer's patch.
诸如豇豆花叶病毒（CPMV）之类的植物病毒因其在植物宿主中产生大量抗原物质的潜力，越来越多地被开发用于纳米生物技术应用，包括疫苗开发。为了提高病毒纳米颗粒在这些类型的作用中的功效，对与颗粒相互作用的单个细胞类型进行研究是至关重要的。特别是，了解潜在疫苗与免疫系统的抗原呈递细胞（APC）的相互作用非常重要。CPMV 先前已被证明与细胞表面上展示的波形蛋白相互作用以介导细胞进入，但 APC 表面波形蛋白的表达尚未得到表征。
通过流式细胞术和荧光共聚焦显微镜，在体外和体内研究了几种 APC 群体对 CPMV 的结合和内化。还通过共聚焦显微镜检查了颗粒与小鼠胃肠道上皮和派尔氏斑的关联。还测量了 APC 表面波形蛋白的表达。
我们发现 CPMV 可通过静脉内、腹腔内和口服给药以及通过胃肠道给药后从派尔氏斑分离的细胞在体外和体内被几种 APC 群体的亚群结合和内化。CPMV 还可内化的 APC 群体也表达表面波形蛋白。这些实验表明 APCs 在体内捕获 CPMV 颗粒，并且进一步调整与表面波形蛋白的相互作用可能有助于增加 APC 的摄取和抗体反应的启动。这些研究还表明，CPMV 颗粒可能通过派尔氏斑在口服给药后通过派尔氏斑进入全身循环。
