Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
Alliance Protein Laboratories, San Diego, CA 92121, United States.
Int J Biol Macromol. 2017 Nov;104(Pt A):650-655. doi: 10.1016/j.ijbiomac.2017.06.085. Epub 2017 Jun 21.
Arginine is widely used as aggregation suppressor of proteins in biotechnology and pharmaceutics. However, why the effect of arginine depends on the types of proteins and stresses, including monoclonal antibodies, is still unclear. Here we investigated the precise processes of the thermal aggregation of human immunoglobulin G (IgG) in the presence of additives. As expected, arginine was the best additive to suppress the formation of insoluble aggregates during heat treatment, though it was unable to preserve the monomer content. A systematic analysis of the additives showed that sugars and kosmotropic ion inhibit the formation of soluble oligomers. These behaviors indicate that the thermal aggregation of IgG occurs by (i) the formation of soluble oligomers, which is triggered by the unfolding process that can be stabilized by typical osmolytes, and (ii) the formation of insoluble aggregates through weak cluster-cluster interactions, which can be suppressed by arginine. Understanding the detailed mechanism of arginine will provide useful information for the rational formulation design of antibodies.
精氨酸被广泛用作生物技术和药物学中蛋白质的聚集抑制剂。然而，为什么精氨酸的效果取决于蛋白质的类型和压力，包括单克隆抗体，这仍然不清楚。在这里，我们研究了在添加剂存在下，人免疫球蛋白 G（IgG）的热聚集的精确过程。正如预期的那样，尽管精氨酸无法保持单体含量，但它是在热处理过程中抑制不溶性聚集体形成的最佳添加剂。对添加剂的系统分析表明，糖和正渗透离子抑制可溶性低聚物的形成。这些行为表明，IgG 的热聚集是通过（i）形成可溶的低聚物来发生的，该过程是由解折叠过程引发的，而典型的渗透剂可以稳定该过程，以及（ii）通过弱的聚集体-聚集体相互作用形成不溶性聚集体，而精氨酸可以抑制该相互作用。了解精氨酸的详细机制将为抗体的合理配方设计提供有用的信息。
