As major eukaryotic lipid storage organelles, lipid droplets (LDs) are metabolic hubs coordinating energy flux and building block distribution. Infectious pathogens often promote accumulation and physically interact with LDs. The most accepted view is that host LDs are hijacked by invaders to draw on nutrients for host colonisation. However, unique traits such as biogenesis plasticity, dynamic proteome, signalling capacity, and ability to interact with other organelles endow LDs with competencies to face complex biological challenges. Here, we focus on published data suggesting that LDs are not usurped organelles but innate immunity first responders. By comparison with analogous mechanisms activated on LDs in nutrient-poor environments, our review supports the hypothesis that host LDs actively participate in immunometabolism, immune signalling, and microbial killing.

作为主要的真核脂质储存细胞器，脂滴 (LD) 是协调能量通量和构建块分布的代谢中心。传染性病原体通常会促进积聚并与 LD 发生物理相互作用。最被接受的观点是，宿主 LD 被入侵者劫持以利用营养物质进行宿主定植。然而，独特的特征，如生物发生可塑性、动态蛋白质组、信号传导能力以及与其他细胞器相互作用的能力，赋予了 LD 应对复杂生物学挑战的能力。在这里，我们关注已发表的数据，这些数据表明 LD 不是被篡夺的细胞器，而是先天免疫第一反应者。通过与在营养贫乏环境中激活 LD 的类似机制进行比较，我们的综述支持宿主 LD 积极参与免疫代谢、免疫信号传导、