School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350, China.
Tianjin Blood Center, Tianjin 300110, China.
J Mater Chem B. 2022 Aug 10;10(31):6038-6048. doi: 10.1039/d2tb01074g.
As a nonreducing disaccharide, trehalose can be used as a biocompatible cryoprotectant for solvent-free cell cryopreservation, but the membrane-impermeability limits its cryoprotective efficiency. Herein, a series of aromatic monoamines with a 1-4 methylene spacer were grafted onto γ-poly(glutamic acid) (γ-PGA) for promoting intracellular trehalose uptake in human red blood cells (hRBCs) membrane perturbation. The self-assembled nanoparticles of the obtained amphiphilic γ-PGA could be adsorbed on the cell membrane by the hydrophobic interaction to disturb the lipid arrangement and increase the membrane permeability of trehalose under hypertonic conditions. Results suggested that the intracellular trehalose could be enhanced progressively with the methylene spacer length, significantly increasing to 75.1 ± 0.7 mM by incubating hRBCs in 0.8 M trehalose containing phenylbutylamine-grafted γ-PGA at 4 °C for 24 h. Meanwhile, the other three polymers exhibited membrane stabilization in addition to improved intracellular trehalose, maintaining the membrane integrity during cryopreservation to achieve high cryosurvival. Molecular dynamics simulation further confirmed that defects could be formed by interaction of the above four amphiphilic polymers on the modeled phospholipid bilayer. It was believed that glycerol-free cryopreservation of human cells could be realized by using trehalose as the biocompatible cryoprotectant, and membrane stabilization can be a compensatory approach to membrane perturbation during impermeable biomolecule delivery.
作为一种非还原二糖，海藻糖可用作无溶剂细胞冷冻保存的生物相容性抗冻剂，但由于其膜不通透性限制了其抗冻保护效率。在此，将一系列带有 1-4 亚甲基间隔基的芳族单胺接枝到γ-聚谷氨酸（γ-PGA）上，以促进人红细胞（hRBC）膜扰动中的细胞内海藻糖摄取。所得两亲性 γ-PGA 的自组装纳米颗粒可以通过疏水性相互作用吸附在细胞膜上，从而扰乱脂质排列并在高渗条件下增加海藻糖的膜通透性。结果表明，细胞内海藻糖可以随着亚甲基间隔基长度的增加而逐渐增强，在 4°C 下孵育 24 小时后，在含有苯丁胺接枝 γ-PGA 的 0.8 M 海藻糖中，细胞内海藻糖可显著增加至 75.1±0.7 mM。同时，另外三种聚合物除了提高细胞内海藻糖外，还表现出膜稳定性，在冷冻保存过程中保持膜完整性，从而实现高冷冻存活率。分子动力学模拟进一步证实，上述四种两亲性聚合物可以在模型磷脂双层上通过相互作用形成缺陷。可以相信，使用海藻糖作为生物相容性抗冻剂可以实现无甘油的人类细胞冷冻保存，而膜稳定性可以作为不可渗透生物分子递送过程中膜扰动的补偿方法。
