Low-density lipoprotein (LDL), one of the four major groups of lipoproteins for lipid transport in vivo, is emerging as an attractive carrier for the targeted delivery of theranostic agents. In contrast to the synthetic systems, LDL particles are intrinsically biocompatible and biodegradable, together with reduced immunogenicity and natural capabilities to target cancerous cells and to escape from the recognition and elimination by the reticuloendothelial system. Enticed by these attributes, a number of strategies have been developed for reconstituting LDL particles, including conjugation to the apolipoprotein, insertion into the phospholipid layer, and loading into the core. Here we present a tutorial review on the development of reconstituted LDL (rLDL) particles for theranostic applications. We start with a brief introduction to LDL and LDL receptor, as well as the advantages of using rLDL particles as a natural and versatile platform for the targeted delivery of theranostic agents. After a discussion of commonly used strategies for the reconstitution of LDL, we highlight the applications of rLDL particles in the staging of disease progression, treatment of lesioned tissues, and delivery of photosensitizers for photodynamic cancer therapy. We finish this review with a perspective on the remaining challenges and future directions.

中文翻译：

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仿生学：低密度脂蛋白的重构用于靶向药物输送和相关治疗诊断应用

低密度脂蛋白（LDL）是体内脂质运输的四大脂蛋白之一，正在成为治疗诊断药物靶向递送的有吸引力的载体。与合成系统相比，低密度脂蛋白颗粒本质上具有生物相容性和可生物降解性，同时具有降低的免疫原性和靶向癌细胞以及逃避网状内皮系统识别和消除的天然能力。受这些属性的吸引，人们开发了许多重建 LDL 颗粒的策略，包括与载脂蛋白缀合、插入磷脂层以及加载到核心中。在这里，我们对用于治疗诊断应用的重组 LDL (rLDL) 颗粒的开发进行了教程回顾。我们首先简要介绍 LDL 和 LDL 受体，以及使用 rLDL 颗粒作为治疗诊断药物靶向递送的天然多功能平台的优势。在讨论了 LDL 重建的常用策略后，我们重点介绍了 rLDL 颗粒在疾病进展分期、病变组织治疗以及光动力癌症治疗中光敏剂输送中的应用。我们以对剩余挑战和未来方向的视角来完成本次审查。