Ac-LETD-AFC is widely used in biochemical research as a fluorogenic substrate for detecting caspase-8 activity. Caspase-8 plays a critical role in apoptosis, and this compound helps researchers study and measure its enzymatic activity in cell-based assays. When cleaved by caspase-8, it releases a fluorescent signal, enabling the quantification of apoptosis in various experimental models. This makes it a valuable tool in cancer research, drug discovery, and studies of programmed cell death mechanisms.