Used in apoptosis research to detect caspase-cleaved cytokeratin 18 fragments in serum or plasma, aiding in the assessment of epithelial cell death. Commonly applied in studies of liver diseases such as NASH, NAFLD, and drug-induced liver injury to monitor disease progression and treatment response. Also utilized in cancer research to evaluate tumor cell apoptosis following chemotherapy or targeted therapies. Provides a non-invasive, quantifiable biomarker for early detection of tissue damage and therapeutic efficacy.