Techniques for monitoring and isolating lipid droplets in cell death

Lipid droplets (LDs) are dynamic organelles that not only store energy and regulate metabolism but also serve as key modulators of cell death signaling and disease progression. LDs influence cell fate by buffering lipid peroxidation or releasing fatty acids during ferroptosis, modulating apoptotic protein expression, and facilitating autophagic degradation. Their multifunctional roles are context-dependent and span multiple cell death pathways. In disease, aberrant LD accumulation is closely linked to metabolic disorders, neurodegeneration, cancer therapy resistance, and pathogen infection. Alterations in LD morphology and abundance have emerged as diagnostic indicators. Thus, precise detection and efficient isolation of LDs are critical for elucidating disease mechanisms, advancing targeted therapies, and translating LD biology into clinical applications. This chapter outlines key methodologies-including lipid staining, fluorescent probes, high-content microscopy, density gradient centrifugation, and immunoaffinity purification-for evaluating lipid droplet function and achieving their isolation in the context of cell death.