High stability of plant-expressed virus-like particles of an insect virus in artificial gastric and intestinal fluids
High stability of plant-expressed virus-like particles of an insect virus in artificial gastric and intestinal fluids
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DOI：
10.1016/j.ejpb.2020.08.012
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发表时间：
2020-10-01
影响因子：
4.9
通讯作者：
Lomonossoff, George P.
中科院分区：
文献类型：
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作者：
Berardi, Alberto;Castells-Graells, Roger;Lomonossoff, George P.
胃肠道（GI）环境的恶劣条件对蛋白质纳米笼的口服递送构成主要障碍。在这里，我们研究了在模拟胃肠道液中的角裸尾虫欧米茄病毒（NcoV）病毒样颗粒（VLP）的稳定性。在植物中瞬时表达NcoV VLP衣壳和原衣壳，将VLP在各种模拟GI液中孵育，并通过凝胶电泳、密度梯度超离心和透射电子显微镜（TEM）测定其稳定性。结果表明，衣壳对pH >= 3的模拟胃液具有高度抵抗力。即使在由pH 1.2的胃蛋白酶溶液组成的最苛刻的条件下，NcoV衣壳仍然组装为VLP，尽管外壳蛋白发生了一些消化。此外，在模拟肠液中孵育4小时后，测量到NcoV衣壳的80.8%（+/-10.2%）稳定性。这种蛋白笼对消化和变性的高抗性可以归因于其独特的紧凑结构。VLP的多孔形式，即原衣壳，在所有条件下都不太稳定。我们的研究结果表明，NcoV VLP衣壳可能耐受通过胃肠道的运输，指定它们为口服药物递送的有前途的候选蛋白纳米笼。
The harsh conditions of the gastro-intestinal (GI) milieu pose a major barrier to the oral delivery of protein nanocages. Here we studied the stability of Nudaurelia capensis omega virus (NcoV) virus-like particles (VLPs) in simulated GI fluids. NcoV VLPs capsids and procapsids were transiently expressed in plants, the VLPs were incubated in various simulated GI fluids and their stability was determined by gel electrophoresis, density gradient ultracentrifugation and transmission electron microscopy (TEM). The results showed that the capsids were highly resistant to simulated gastric fluids at pH >= 3. Even under the harshest conditions, which consisted of a pepsin solution at pH 1.2, NcoV capsids remained assembled as VLPs, though some digestion of the coat protein occurred. Moreover, 80.8% ( +/- 10.2%) stability was measured for NcoV capsids upon 4 h incubation in simulated intestinal fluids. The high resistance of this protein cage to digestion and denaturation can be attributed to its distinctively compact structure. The more porous form of the VLPs, the procapsid, was less stable under all conditions. Our results suggest that NcoV VLPs capsids are likely to endure transit through the GI tract, designating them as promising candidate protein nanocages for oral drug delivery.