School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Biomacromolecules. 2020 Dec 14;21(12):5345-5357. doi: 10.1021/acs.biomac.0c01465. Epub 2020 Dec 2.
Efficient therapeuic proteins' delivery into mammalian cells and subcellular transport (e.g., fast escape from endolysosomes into cytoplasm) are two key biological barriers that need to be overcome for antigen-based immunotherapy and related biomedical applications. For those purposes, we designed a novel kind of photoresponsive polypeptide-glycosylated poly(amidoamine) (PAMAM) dendron amphiphiles (PGDAs), and their synthesis, UV-responsive self-assembly, and triggered ovalbumin (OVA) release have been fully investigated. The highly anisotropic PGDA with a glycosylated second-generation PAMAM dendron self-assembled into stable polypeptide vesicles (polymersomes) within 20-50 wt % water, which exhibited UV-responsive reassembly, dynamic binding with a lectin of concanavalin A, and an accelerated OVA release in vitro. Moreover, upon 365 nm UV irradiation, the self-assembled polymersomes of those glycopolypeptides were transformed into micellar aggregates in aqueous solution at pH 7.4 but disassembled completely at pH 5. The OVA-loaded polymersomes could efficiently deliver OVA into RAW264.7 cells and achieve enhanced endolysosomes escape upon UV irradiation, as revealed by flow cytometry and confocal laser scanning microscopy (CLSM). Furthermore, the enzyme-linked immunosorbent assay (ELISA) showed that the blank sugar-coated polypeptidosomes activated a high level of tumor necrosis factor α (TNF-α) of 468 pg/mL, playing a better role of immune adjuvant for activating the macrophages. Upon the UV irradiation with a dose of 3 J/cm, the OVA-loaded polymersomes could further stimulate RAW264.7 and enhance the TNF-α level by about 45%. Consequently, this work provides a versatile platform to construct photosensitive and sugar-coated polymersomes of glycopolypeptides that have potential applications for protein delivery, immune adjuvant, and antigen-based immunotherapy.
高效的治疗性蛋白递送入哺乳动物细胞和亚细胞转运（例如，快速从内涵体逃逸到细胞质）是基于抗原的免疫治疗和相关生物医学应用需要克服的两个关键生物学障碍。为此，我们设计了一种新型光响应的多肽-糖基化聚（酰胺-胺）（PAMAM）树枝状两亲物（PGDAs），并对其合成、紫外响应自组装和触发卵清蛋白（OVA）释放进行了全面研究。具有糖基化第二代 PAMAM 树枝状结构的各向异性高度 PGDA 可在 20-50wt%的水中自组装成稳定的多肽囊泡（聚合物囊泡），其具有紫外响应的再组装、与伴刀豆球蛋白 A 的凝集素的动态结合以及体外加速 OVA 释放的特性。此外，在 365nm 紫外光照射下，这些糖基化多肽的自组装聚合物囊泡在 pH7.4 的水溶液中转化为胶束聚集体，但在 pH5 时完全解体。负载 OVA 的聚合物囊泡可有效将 OVA 递送入 RAW264.7 细胞，并在紫外光照射下实现增强的内涵体逃逸，这可通过流式细胞术和共聚焦激光扫描显微镜（CLSM）证实。此外，酶联免疫吸附测定（ELISA）表明，空白糖包被的多肽纳米囊泡激活了 468pg/mL 的高水平肿瘤坏死因子-α（TNF-α），作为免疫佐剂发挥了更好的作用，可激活巨噬细胞。在 3J/cm 的紫外光照射下，负载 OVA 的聚合物囊泡可进一步刺激 RAW264.7 并将 TNF-α 水平提高约 45%。因此，这项工作提供了一个多功能平台，用于构建具有光响应性和糖涂层的糖基化多肽聚合物囊泡，其在蛋白质递送、免疫佐剂和基于抗原的免疫治疗方面具有潜在应用。
